Tektronix 707A Instruction Manual

Model 707A

Switching Matrix

Instruction Manual

707A-901-01 Rev. A / 9-98

Contains Operating and Servicing Information

W ARRANTY

Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a period of 1 year from date of
shipment.

Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries,
diskettes, and documentation.

During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.

To exercise this warranty, write or call your local Keithley representati v e, or contact Keithley headquarters in Cleveland, Ohio. You will
be given prompt assistance and return instructions. Send the product, transportation prepaid, to the indicated service facility. Repairs
will be made and the product returned, transportation prepaid. Repaired or replaced products are warranted for the balance of the origi­nal warranty period, or at least 90 days.

LIMIT A TION OF W ARRANTY

This warranty does not apply to defects resulting from product modification without Keithley’s express written consent, or misuse of
any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or
problems arising from normal wear or failure to follow instructions.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE REMEDIES PROVIDED HEREIN ARE
BUYER’S SOLE AND EXCLUSIVE REMEDIES.

NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT, INDI­RECT , SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INSTRUMENTS AND
SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF
SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS OF REMOVAL
AND INSTALLATION, LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PROPERTY.

Keithley Instruments, Inc. • 28775 Aurora Road • Cleveland, OH 44139 • 440-248-0400 • Fax: [phone] • http://www.keithley.com

CHINA: Keithley Instruments China • Yuan Chen Xin Building, Room 705 • 12 Yumin Road, Dewai, Madian • Beijing 100029 • 8610-62022886 • Fax: [phone]
FRANCE: Keithley Instruments SARL • BP 60 • 3 Allée des Garays • 91122 Palaiseau Cédex • 33-1-60-11-51-55 • Fax: [phone]
GERMANY: Keithley Instruments GmbH • Landsberger Strasse 65 • D-82110 Germering, Munich • 49-89-8493070 • Fax: [phone]
GREAT BRITAIN: Keithley Instruments, Ltd. • The Minster • 58 Portman Road • Reading, Berkshire RG30 1EA • 44-1189-596469 • Fax: [phone]
ITALY: Keithley Instruments SRL • Viale S. Gimignano 38 • 20146 Milano • 39-2-48303008 • Fax: [phone]
NETHERLANDS: Keithley Instruments BV • Avelingen West 49 • 4202 MS Gorinchem • 31-(0)183-635333 • Fax: [phone]
SWITZERLAND: Keithley Instruments SA • Kriesbachstrasse 4 • 8600 Dübendorf • 41-1-8219444 • Fax: [phone]
TAIWAN: Keithley Instruments Taiwan • 1FL., 85 Po Ai Street • Hsinchu, Taiwan • 886-35-778462 • Fax: [phone]

Model 707A Switching Matrix

Instruction Manual

©1998, Keithley Instruments, Inc.

All rights reserved.

Cleveland, Ohio, U.S.A.

First Printing, September 1998

Document Number: 707A-901-01 Rev. A

Manual Print History

The print history shown below lists the printing dates of all Revisions and Addenda created for this manual. The Revision
Level letter increases alphabetically as the manual undergoes subsequent updates. Addenda, which are released between Revi­sions, contain important change information that the user should incorporate immediately into the manual. Addenda are num­bered sequentially. When a new Revision is created, all Addenda associated with the previous Revision of the manual are
incorporated into the new Revision of the manual. Each new Revision includes a revised copy of this print history page.

Revision A (Document Number 707A-901-01) ............................................................................ September 1998

All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand and product names are trademarks or registered trademarks of their respective holders.

Safety Precautions

The following safety precautions should be observed before using
this product and any associated instrumentation. Although some in­struments and accessories would normally be used with non-haz­ardous voltages, there are situations where hazardous conditions
may be present.

This product is intended for use by qualified personnel who recog­nize shock hazards and are familiar with the safety precautions re­quired to avoid possible injury. Read the operating information
carefully before using the product.

The types of product users are:

Responsible body is the individual or group responsible for the use

and maintenance of equipment, and for ensuring that operators are
adequately trained.

Operators use the product for its intended function. They must be

trained in electrical safety procedures and proper use of the instru­ment. They must be protected from electric shock and contact with
hazardous live circuits.

Maintenance personnel perform routine procedures on the product

to keep it operating, for example, setting the line voltage or replac­ing consumable materials. Maintenance procedures are described in
the manual. The procedures explicitly state if the operator may per­form them. Otherwise, they should be performed only by service
personnel.

Service personnel are trained to work on live circuits, and perform

safe installations and repairs of products. Only properly trained ser­vice personnel may perform installation and service procedures.

Exercise extreme caution when a shock hazard is present. Lethal
voltage may be present on cable connector jacks or test fixtures. The
American National Standards Institute (ANSI) states that a shock
hazard exists when voltage levels greater than 30V RMS, 42.4V
peak, or 60VDC are present. A good safety practice is to expect

that hazardous voltage is present in any unknown circuit bef ore
measuring.

Users of this product must be protected from electric shock at all
times. The responsible body must ensure that users are prevented
access and/or insulated from every connection point. In some cases,
connections must be exposed to potential human contact. Product
users in these circumstances must be trained to protect themselves
from the risk of electric shock. If the circuit is capable of operating
at or above 1000 volts, no conductive part of the circuit may be

exposed.

As described in the International Electrotechnical Commission
(IEC) Standard IEC 664, digital multimeter measuring circuits
(e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010)
measuring circuits are Installation Category II. All other instru­ments’ signal terminals are Installation Category I and must not be
connected to mains.

Do not connect switching cards directly to unlimited power circuits.
They are intended to be used with impedance limited sources.
NEVER connect switching cards directly to AC mains. When con­necting sources to switching cards, install protective devices to lim­it fault current and voltage to the card.

Before operating an instrument, make sure the line cord is connect­ed to a properly grounded power receptacle. Inspect the connecting
cables, test leads, and jumpers for possible wear, cracks, or breaks
before each use.

For maximum safety, do not touch the product, test cables, or any
other instruments while power is applied to the circuit under test.
ALWAYS remove power from the entire test system and discharge
any capacitors before: connecting or disconnecting cables or jump­ers, installing or removing switching cards, or making internal
changes, such as installing or removing jumpers.

Do not touch any object that could provide a current path to the
common side of the circuit under test or power line (earth) ground.
Always make measurements with dry hands while standing on a
dry, insulated surface capable of withstanding the voltage being
measured.

Do not exceed the maximum signal levels of the instruments and ac­cessories, as defined in the specifications and operating informa­tion, and as shown on the instrument or test fixture panels, or
switching card.

When fuses are used in a product, replace with same type and rating
for continued protection against fire hazard.

Chassis connections must only be used as shield connections for
measuring circuits, NOT as safety earth ground connections.

If you are using a test fixture, keep the lid closed while power is ap­plied to the device under test. Safe operation requires the use of a
lid interlock.

If a screw is present, connect it to safety earth ground using the
wire recommended in the user documentation.

!

The symbol on an instrument indicates that the user should re­fer to the operating instructions located in the manual.

The symbol on an instrument shows that it can source or mea­sure 1000 volts or more, including the combined effect of normal
and common mode voltages. Use standard safety precautions to
avoid personal contact with these voltages.

The WARNING heading in a manual explains dangers that might
result in personal injury or death. Alw ays read the associated infor ­mation very carefully before performing the indicated procedure.

Instrumentation and accessories shall not be connected to humans.

Before performing any maintenance, disconnect the line cord and
all test cables.

To maintain protection from electric shock and fire, replacement
components in mains circuits, including the power transformer, test
leads, and input jacks, must be purchased from Keithley Instru­ments. Standard fuses, with applicable national safety approvals,
may be used if the rating and type are the same. Other components
that are not safety related may be purchased from other suppliers as
long as they are equivalent to the original component. (Note that se­lected parts should be purchased only through Keithley Instruments
to maintain accuracy and functionality of the product.) If you are
unsure about the applicability of a replacement component, call a
Keithley Instruments office for information.

To clean the instrument, use a damp cloth or mild, water based
cleaner. Clean the exterior of the instrument only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill
on the instrument.

The CAUTION heading in a manual explains hazards that could
damage the instrument. Such damage may invalidate the warranty.

707A Switching Matrix Specifications

Overview

CAPACITY: Six plug-in cards per mainframe.
EXPANSION CAPACITY: Daisy-chain expansion of up to four Slave units with one

Master unit.

ANALOG BACKPLANES: Backplanes provide automatic row expansion between

similar cards within one mainframe.

DISPLAY:14-segment alphanumeric LED display, plus individual status LEDs.
MEMORY:Storage for 100 matrix setups, lithium battery backup.
PROGRAMMED SETTING TIME: 0 to 65 seconds in 1ms increments.
FRONT PANEL MENU: Digital I/O; External Trigger edge; Matrix Ready level; Master/

Slave operation; IEEE-488 address; Relay Settling Time; Self Test; Card Identify;
factory defaults.

TRIGGER SOURCES: External Trigger (TTL compatible, programmable edge, 600ns

minimum pulse width); IEEE-488 bus (TALK, GET, “X”); manual.

STATUS OUTPUT: Matrix Ready (TTL compatible, programmable high or low true):

goes false when relays are switched, true at end of Programmed Settling Time.

MAKE BEFORE BREAK, BREAK BEFORE MAKE: Programmable by row.
LIGHT PEN OPTION: Controls crosspoints, memories, make before break and break

before make. One light pen controls Master and all Slaves.

Execution Speed

MAXIMUM TRIGGER RATE: 200 setups per second (stepping through previously

stored setups with make-before-break and break-before-make disabled).

TRIGGER RESPONSE TIME:

External Trigger: <1ms.
IEEE-488 GET: <1ms.

RESPONSE TO IEEE-488 COMMAND (to close a single relay, excluding relay settling

time):
Stand Alone: <15ms.
Master and Four Slaves: <55ms.

DOWNLOAD TIME (one setup to 707A):

Stand Alone: 60ms typical.

IEEE-488 BUS IMPLEMENTATION

MULTILINE COMMANDS:DCL, LLO, SDC, GET, GTL, UNT, UNL, SPE, SPD
UNILINE COMMANDS: IFC, REN, EOI, SRQ, ATN.
INTERFACE FUNCTIONS: SH1, AH1, T6, TE0, L4, LE0, SR1, RL1, PP0, DC1, DT1, C0, E1.
PROGRAMMABLE PARAMETERS: All parameters programmable except for IEEE-

488 bus address and Master/Slave operating mode.

GENERAL

DIGITAL I/O (TTL compatible):

Data: 8 inputs, 8 outputs.
Control: Input Latch, Output Strobe.

REAR PANEL CONNECTORS:

Two BNC: External Trigger, Matrix Ready.
One DB-25: Digital I/O.
Two 8-pin DIN: Mater/Slave In, Mater/Slave Out.
One 6-pin Screw Terminal Plug: Relay Test.

ENVIRONMENTAL:

Operating: 0 to 50 C.

Storage: –25 to 65 C.
POWER: 100 to 240 VAC, 50–60Hz, 250VA maximum.
RELAY DRIVE: 5A minimum per card (slot).
EMC: Conforms with European Union Directive 89/336/EEC EN 55011,

EN 50082-1, EN 61000-3-3, FCC part 15 class B.

SAFETY: Conforms with European Union Directive 73/23/EEC EN 61010-1.
PHYSICAL: 356mm high ×432mm wide × 574mm deep (14 in × 17 in × 22.6 in). Net

weight without cards 16.5kg (36 lbs).
ACCESSORIES SUPPLIED: Instruction manual, power line cord, relay test

connector, fixed rack mounting hardware.

ACCESSORIES AVAILABLE:

Model 7078-PEN:Programming Light Pen (includes holder)

Model 7079: Slide Rack Mounting Kit

Model 7078-DIN: 8-pin DIN cable (Master/Slave), 1.8m (6ft.)

Specifications are subject to change without notice.

Table of Contents

1 General Information

1.1 Introduction ........................................................................................................................................................ 1-1

1.2 Features .............................................................................................................................................................. 1-1

1.3 Warranty information ......................................................................................................................................... 1-1

1.4 Manual addenda ................................................................................................................................................. 1-1

1.5 Safety symbols and terms .................................................................................................................................. 1-2

1.6 Specifications ..................................................................................................................................................... 1-2

1.7 Unpacking and inspection .................................................................................................................................. 1-2

1.7.1 Inspection for damage .............................................................................................................................. 1-2

1.7.2 Shipment contents..................................................................................................................................... 1-2

1.8 Repacking for shipment ..................................................................................................................................... 1-2

1.9 Optional accessories ........................................................................................................................................... 1-2

2 Card Installation

2.1 Installing and removing cards ............................................................................................................................ 2-1

3 Getting Started

3.1 Introduction ........................................................................................................................................................ 3-1

3.2 Front panel familiarization ................................................................................................................................. 3-1

3.3 Rear panel familiarization .................................................................................................................................. 3-6

3.4 Card connections ................................................................................................................................................ 3-8

3.5 Expanding matrix size ...................................................................................................................................... 3-10

3.5.1 Single unit expansion ............................................................................................................................. 3-10

3.5.2 Multiple unit expansion ......................................................................................................................... 3-16

3.5.3 System expansion issues ........................................................................................................................ 3-20

3.5.4 Documenting system configuration ....................................................................................................... 3-20

3.6 Basic switching operation ................................................................................................................................ 3-22

3.6.1 Power-up ................................................................................................................................................ 3-22

3.6.2 Selecting make/break and break/make rows .......................................................................................... 3-22

3.6.3 Modifying a relay setup ......................................................................................................................... 3-22

3.6.4 Storing setup and sending to relays ........................................................................................................ 3-23

i

4 Operation

4.1 Introduction ........................................................................................................................................................ 4-1

4.2 Setup data paths ................................................................................................................................................. 4-1

4.3 Power-up procedure ........................................................................................................................................... 4-2

4.3.1 Line voltage selection .............................................................................................................................. 4-2

4.3.2 Line power connections ........................................................................................................................... 4-2

4.3.3 Power switch ............................................................................................................................................ 4-2

4.3.4 Power-up self-test and messages ............................................................................................................. 4-2

4.3.5 Power-up configuration ........................................................................................................................... 4-3

4.3.6 Master/slave power-up ............................................................................................................................. 4-4

4.4 Displays and messages ...................................................................................................................................... 4-4

4.4.1 Alphanumeric display .............................................................................................................................. 4-4

4.4.2 Display messages ..................................................................................................................................... 4-5

4.4.3 IEEE-488 status indicators ...................................................................................................................... 4-6

4.4.4 Crosspoint display LEDs ......................................................................................................................... 4-6

4.4.5 Make/break and break/make LEDs ......................................................................................................... 4-8

4.4.6 Light pen .................................................................................................................................................. 4-8

4.5 Selecting crosspoint display ............................................................................................................................ 4-10

4.6 Modifying crosspoint display .......................................................................................................................... 4-10

4.7 Copying crosspoint display .............................................................................................................................. 4-11

4.8 Inserting and deleting stored setups ................................................................................................................. 4-12

4.9 Menu operations .............................................................................................................................................. 4-12

4.9.1 Digital I/O .............................................................................................................................................. 4-14

4.9.2 External trigger ...................................................................................................................................... 4-14

4.9.3 Matrix ready ........................................................................................................................................... 4-15

4.9.4 Stand-alone and master/slave ................................................................................................................ 4-16

4.9.5 IEEE-488 bus address ............................................................................................................................ 4-17

4.9.6 Relay (hardware) settling times ............................................................................................................. 4-18

4.9.7 Card labels ............................................................................................................................................. 4-18

4.9.8 Self-test .................................................................................................................................................. 4-18

4.9.9 Factory defaults ..................................................................................................................................... 4-18

4.10 Selecting switching parameters ....................................................................................................................... 4-19

4.10.1 Programmed settling time ...................................................................................................................... 4-19

4.10.2 Make/break and break/make rows ......................................................................................................... 4-19

4.11 Triggering ........................................................................................................................................................ 4-20

4.11.1 Trigger sources ...................................................................................................................................... 4-20

4.11.2 Front panel triggering ............................................................................................................................ 4-21

4.11.3 Trigger overrun conditions .................................................................................................................... 4-21

4.11.4 External trigger input ............................................................................................................................. 4-25

4.11.5 Matrix ready output ............................................................................................................................... 4-25

4.11.6 IEEE-488 bus triggering ........................................................................................................................ 4-25

4.12 Resetting .......................................................................................................................................................... 4-25

ii

5 IEEE-488 Programming

5.1 Introduction ........................................................................................................................................................ 5-1

5.2 IEEE-488 quick start .......................................................................................................................................... 5-1

5.3 Bus cable connections ........................................................................................................................................ 5-3

5.4 Interface function codes ..................................................................................................................................... 5-5

5.5 Primary address programming ........................................................................................................................... 5-6

5.6 QuickBASIC programming ............................................................................................................................... 5-7

5.7 Front panel aspects of IEEE-488 operation ....................................................................................................... 5-8

5.7.1 Front panel error messages ...................................................................................................................... 5-8

5.7.2 Status indicators ....................................................................................................................................... 5-9

5.7.3 Local key ................................................................................................................................................ 5-10

5.7.4 Concurrent front panel and bus operation .............................................................................................. 5-10

5.8 General bus command programming ............................................................................................................... 5-10

5.8.1 Overview ................................................................................................................................................ 5-10

5.8.2 REN (remote enable) ............................................................................................................................. 5-10

5.8.3 IFC (interface clear) ............................................................................................................................... 5-11

5.8.4 LLO (local lockout) ............................................................................................................................... 5-11

5.8.5 GTL (go to local) ................................................................................................................................... 5-11

5.8.6 DCL (device clear) ................................................................................................................................. 5-11

5.8.7 SDC (selective device clear) .................................................................................................................. 5-11

5.8.8 GET (group executive trigger) ............................................................................................................... 5-11

5.8.9 SPE, SPD ( serial polling) ...................................................................................................................... 5-11

5.9 Device-dependent command (DDC) programming ......................................................................................... 5-12

5.9.1 Overview ................................................................................................................................................ 5-12

5.9.2 A — External trigger .............................................................................................................................. 5-16

5.9.3 B — Matrix ready .................................................................................................................................. 5-17

5.9.4 C — Close crosspoint ............................................................................................................................ 5-18

5.9.5 D — Display .......................................................................................................................................... 5-18

5.9.6 E — Edit pointer .................................................................................................................................... 5-19

5.9.7 F — Enable/disable triggers ................................................................................................................... 5-19

5.9.8 G — Data format .................................................................................................................................... 5-20

5.9.9 H — Hit key ........................................................................................................................................... 5-25

5.9.10 I — Insert blank setup ............................................................................................................................ 5-26

5.9.11 J — Self-test ........................................................................................................................................... 5-26

5.9.12 K — EOI and hold-off ........................................................................................................................... 5-26

5.9.13 L — Download setups ............................................................................................................................ 5-27

5.9.14 M — SRQ and serial poll byte ............................................................................................................... 5-28

5.9.15 N — Open crosspoint ............................................................................................................................. 5-30

5.9.16 O — Digital output ................................................................................................................................ 5-30

5.9.17 P — Clear crosspoints ............................................................................................................................ 5-31

5.9.18 Q — Delete setup ................................................................................................................................... 5-31

5.9.19 R — Restore defaults ............................................................................................................................. 5-32

5.9.20 S — Programmed settling time .............................................................................................................. 5-32

5.9.21 T — Trigger ........................................................................................................................................... 5-33

5.9.22 U — Status ............................................................................................................................................. 5-34

5.9.23 V — Make/break .................................................................................................................................... 5-39

5.9.24 W — Break/make ................................................................................................................................... 5-39

5.9.25 X — Execute .......................................................................................................................................... 5-40

5.9.26 Y — Terminator ..................................................................................................................................... 5-41

5.9.27 Z — Copy setup ..................................................................................................................................... 5-41

5.10 Relay command combinations ......................................................................................................................... 5-42

5.11 Timing considerations ...................................................................................................................................... 5-43

iii

6 Principles of Operation

6.1 Introduction ........................................................................................................................................................ 6-1

6.2 Overall function description .............................................................................................................................. 6-1

6.3 Microcomputer .................................................................................................................................................. 6-1

6.3.1 Reset circuit ............................................................................................................................................. 6-1

6.3.2 Address decoding ..................................................................................................................................... 6-2

6.3.3 Memory .................................................................................................................................................... 6-4

6.4 Relay control circuitry ....................................................................................................................................... 6-4

6.4.1 Switching card interface .......................................................................................................................... 6-6

6.4.2 Switching card logic ................................................................................................................................ 6-6

6.5 Display circuitry .............................................................................................................................................. 6-10

6.5.1 Display data ........................................................................................................................................... 6-13

6.5.2 Front panel keys ..................................................................................................................................... 6-13

6.5.3 Display interface .................................................................................................................................... 6-13

6.5.4 Refresh display/read keyboard .............................................................................................................. 6-14

6.6 Light pen interface............................................................................................................................................ 6-14

6.7 Master/slave circuitry ...................................................................................................................................... 6-15

6.7.1 Serial communication ............................................................................................................................ 6-15

6.7.2 Control signals ....................................................................................................................................... 6-17

6.8 Digital I/O ........................................................................................................................................................ 6-17

6.9 IEEE-488 bus interface .................................................................................................................................... 6-17

6.10 Power supply ................................................................................................................................................... 6-19

7 Maintenance

7.1 Introduction ........................................................................................................................................................ 7-1

7.2 Line voltage sensing .......................................................................................................................................... 7-1

7.3 Fuse replacement ............................................................................................................................................... 7-2

7.4 Fixed rack installation ........................................................................................................................................ 7-2

7.5 Disassembly ....................................................................................................................................................... 7-5

7.6 Backplane jumpers ............................................................................................................................................. 7-7

7.7 Battery replacement ........................................................................................................................................... 7-9

7.8 Static-sensitive devices ...................................................................................................................................... 7-9

7.9 Mainframe troubleshooting ............................................................................................................................... 7-9

7.9.1 Recommended test equipment ............................................................................................................... 7-10

7.9.2 Power-up self-test .................................................................................................................................. 7-10

7.9.3 Power supply checks .............................................................................................................................. 7-10

7.9.4 Digital board checks .............................................................................................................................. 7-10

7.9.5 Display board checks ............................................................................................................................. 7-14

7.10 Using an extender card .................................................................................................................................... 7-16

7.11 Cleaning ........................................................................................................................................................... 7-16

7.11.1 Backplane .............................................................................................................................................. 7-16

7.11.2 Fan filter ................................................................................................................................................. 7-16

8 Replaceable Parts

8.1 Introduction ........................................................................................................................................................ 8-1

8.2 Parts lists ............................................................................................................................................................ 8-1

8.3 Ordering information ......................................................................................................................................... 8-1

8.4 Factory service ................................................................................................................................................... 8-1

8.5 Component layouts and schematics ................................................................................................................... 8-1

iv

A Card Configuration Worksheet

B IEEE-488 Bus Overview

B.1 Introduction ....................................................................................................................................................... B-1

B.2 Bus description .................................................................................................................................................. B-1

B.3 Bus lines ............................................................................................................................................................ B-3

B.3.1 Data lines ................................................................................................................................................. B-3

B.3.2 Bus management lines ............................................................................................................................ B-3

B.3.3 Handshake lines ...................................................................................................................................... B-3

B.4 Bus commands .................................................................................................................................................. B-4

B.4.1 Uniline commands .................................................................................................................................. B-4

B.4.2 Universal multiline commands ............................................................................................................... B-5

B.4.3 Addressed multiline commands .............................................................................................................. B-5

B.4.4 Address commands ................................................................................................................................. B-5

B.4.5 Unaddress commands ............................................................................................................................. B-5

B.4.6 Command codes ...................................................................................................................................... B-5

B.4.7 Typical command sequences .................................................................................................................. B-7

B.4.8 IEEE command groups ........................................................................................................................... B-7

B.5 Interface function codes .................................................................................................................................... B-8

v

List of Illustrations

2 Card Installation

Figure 2-1 Installing a matrix card .............................................................................................................................. 2-2

3 Getting Started

Figure 3-1 Model 707A front panel ............................................................................................................................. 3-2

Figure 3-2 Setup data transfers .................................................................................................................................... 3-3

Figure 3-3 Model 707A rear panel .............................................................................................................................. 3-7

Figure 3-4 Connecting instruments to rows ................................................................................................................. 3-8

Figure 3-5 Connecting instruments to columns ........................................................................................................... 3-9

Figure 3-6 Backplane buses ....................................................................................................................................... 3-10

Figure 3-7 Backplane expansion of analog bus #1 .................................................................................................... 3-11

Figure 3-8 Backplane expansion of analog bus #2 .................................................................................................... 3-12

Figure 3-9 Backplane expansion of analog bus #3 .................................................................................................... 3-13

Figure 3-10 Row connection examples ....................................................................................................................... 3-14

Figure 3-11 Example of partial matrix expansion ....................................................................................................... 3-15

Figure 3-12 Model 7071 row connections of stand-alone units .................................................................................. 3-16

Figure 3-13 Example of master/slave interconnect cables .......................................................................................... 3-17

Figure 3-14 Master/slave column locations ................................................................................................................. 3-18

Figure 3-15 Example of master/slave row expansion .................................................................................................. 3-19

4 Operation

Figure 4-1 Paths for relay setup data ........................................................................................................................... 4-1

Figure 4-2 Alphanumeric display ................................................................................................................................ 4-4

Figure 4-3 Crosspoint display ...................................................................................................................................... 4-7

Figure 4-4 Light pen .................................................................................................................................................... 4-9

Figure 4-5 Crosspoint display keys ........................................................................................................................... 4-10

Figure 4-6 Data entry keys ......................................................................................................................................... 4-11

Figure 4-7 Memory keys ............................................................................................................................................ 4-12

Figure 4-8 Digital I/O port ......................................................................................................................................... 4-14

Figure 4-9 Rear panel BNC jacks .............................................................................................................................. 4-14

Figure 4-10 Sample external trigger pulses ................................................................................................................. 4-15

Figure 4-11 Sample matrix ready pulses ..................................................................................................................... 4-15

Figure 4-12 Master/slave connectors ........................................................................................................................... 4-16

Figure 4-13 IEEE-488 bus connector .......................................................................................................................... 4-17

Figure 4-14 Switching keys ......................................................................................................................................... 4-19

Figure 4-15 Trigger keys ............................................................................................................................................. 4-20

Figure 4-16 Timing without make/break or break/make rows .................................................................................... 4-22

Figure 4-17 Timing with either make/break or break/make rows ............................................................................... 4-23

Figure 4-18 Timing with both make/break and break/make rows ............................................................................... 4-24

vii

5 IEEE-488 Programming

Figure 5-1 Flowchart of example program .................................................................................................................. 5-2

Figure 5-2 IEEE-488 connector ................................................................................................................................... 5-3

Figure 5-3 IEEE-488 connections ............................................................................................................................... 5-3

Figure 5-4 IEEE-488 connector location ..................................................................................................................... 5-4

Figure 5-5 Contact assignments .................................................................................................................................. 5-5

Figure 5-6 IEEE-488 indicators ................................................................................................................................... 5-9

Figure 5-7 LOCAL key ............................................................................................................................................. 5-10

Figure 5-8 External trigger pulse ............................................................................................................................... 5-16

Figure 5-9 Matrix ready pulse ................................................................................................................................... 5-17

Figure 5-10 G0 and G1 full output formats ................................................................................................................. 5-22

Figure 5-11 G2 and G3 inspect output formats ........................................................................................................... 5-23

Figure 5-12 G4 and G5 condensed output formats ..................................................................................................... 5-23

Figure 5-13 G6 and G7 binary output formats ............................................................................................................ 5-24

Figure 5-14 SRQ mask and serial poll byte format ..................................................................................................... 5-28

Figure 5-15 READY and MATRIX READY signal timing ....................................................................................... 5-33

Figure 5-16 U0 machine status word ........................................................................................................................... 5-35

Figure 5-17 U1 error status word ................................................................................................................................ 5-35

Figure 5-18 U3 relay step pointer ................................................................................................................................ 5-36

Figure 5-19 U4 number of slaves ................................................................................................................................ 5-37

Figure 5-20 U5 card identification .............................................................................................................................. 5-37

Figure 5-21 U6 relay settling time ............................................................................................................................... 5-37

Figure 5-22 U7 digital input ........................................................................................................................................ 5-38

Figure 5-23 U8 relay test input .................................................................................................................................... 5-38

6 Principles of Operation

Figure 6-1 Model 707A block diagram ....................................................................................................................... 6-2

Figure 6-2 Digital board block diagram ...................................................................................................................... 6-3

Figure 6-3 RAM and battery backup ........................................................................................................................... 6-5

Figure 6-4 Switching card interface simplified schematic .......................................................................................... 6-7

Figure 6-5 Switching card interface timing diagram ................................................................................................... 6-8

Figure 6-6 Typical switching card logic block diagram .............................................................................................. 6-8

Figure 6-7 IDDATA timing diagram .......................................................................................................................... 6-9

Figure 6-8 Display board diagram ............................................................................................................................. 6-11

Figure 6-9 Display interface simplified schematic .................................................................................................... 6-13

Figure 6-10 Light pen interface simplified schematic ................................................................................................. 6-14

Figure 6-11 Master/slave interface simplified schematic ............................................................................................. 6-16

Figure 6-12 Digital I/O interface simplified schematic ............................................................................................... 6-18

7 Maintenance

Figure 7-1 Captive nut installation .............................................................................................................................. 7-3

Figure 7-2 Nut bar on flange ....................................................................................................................................... 7-3

Figure 7-3 Chassis support sizing ................................................................................................................................ 7-4

Figure 7-4 Chassis support assembly .......................................................................................................................... 7-4

Figure 7-5 Right side view of disassembly ................................................................................................................. 7-5

Figure 7-6 Front view of disassembly ......................................................................................................................... 7-6

Figure 7-7 Backplane jumpers ..................................................................................................................................... 7-8

Figure 7-8 Troubleshooting programs ....................................................................................................................... 7-14

Figure 7-9 Relay control waveforms ......................................................................................................................... 7-15

Figure 7-10 Display interface waveforms ................................................................................................................... 7-15

viii

B IEEE-488 Bus Overview

Figure B-1 IEEE-488 bus configuration ...................................................................................................................... B-2

Figure B-2 IEEE-488 handshake sequence ................................................................................................................. B-3

Figure B-3 Command codes ........................................................................................................................................ B-6

ix

List of Tables

3 Getting Started

Table 3-1 Row-column and column-column paths .................................................................................................... 3-9

Table 3-2 Matrix and multiplexer cards ................................................................................................................... 3-13

Table 3-3 Model 707A external expansion cables ................................................................................................... 3-15

Table 3-4 Response time comparisons ..................................................................................................................... 3-20

Table 3-5 Model 707A card configuration ............................................................................................................... 3-21

4 Operation

Table 4-l Setup data paths ......................................................................................................................................... 4-2

Table 4-2 Power-up, reset, and factory defaults ......................................................................................................... 4-3

Table 4-3 Error messages ........................................................................................................................................... 4-5

Table 4-4 Information messages ................................................................................................................................ 4-6

Table 4-5 Menu operations ....................................................................................................................................... 4-13

Table 4-6 Status of slave unit controls ..................................................................................................................... 4-17

Table 4-7 Make/break and break/make front panel operation .................................................................................. 4-20

Table 4-8 Front panel messages for trigger sources ................................................................................................. 4-20

5 IEEE-488 Programming

Table 5-1 Sample strings ............................................................................................................................................ 5-2

Table 5-2 Contact assignments ................................................................................................................................... 5-5

Table 5-3 Model 707A interface function codes ........................................................................................................ 5-6

Table 5-4 Basic IEEE-488 statements ........................................................................................................................ 5-7

Table 5-5 Front panel IEEE-488 error messages ........................................................................................................ 5-8

Table 5-6 General bus commands/BASIC statements ............................................................................................. 5-11

Table 5-7 Factory default, power-up, and DCL/SDC conditions ............................................................................. 5-12

Table 5-8 Order of command execution ................................................................................................................... 5-13

Table 5-9 DDC summary ......................................................................................................................................... 5-14

Table 5-10 Master/slave setup example ..................................................................................................................... 5-21

Table 5-11 Byte counts for data format ...................................................................................................................... 5-22

Table 5-12 Typical transmission and hold-off times — stand-alone ......................................................................... 5-44

Table 5-13 Typical transmission and hold-off times — master and one slave .......................................................... 5-45

6 Principles of Operation

Table 6-1 Display segment assignments .................................................................................................................. 6-12

xi

7 Maintenance

Table 7-1 Line fuse values ......................................................................................................................................... 7-2

Table 7-2 Fixed rack parts .......................................................................................................................................... 7-2

Table 7-3 Recommended troubleshooting equipment ............................................................................................. 7-10

Table 7-4 Power supply checks ................................................................................................................................ 7-10

Table 7-5 Microcomputer checks ............................................................................................................................. 7-11

Table 7-6 Relay control checks ................................................................................................................................ 7-11

Table 7-7 Display interface checks .......................................................................................................................... 7-12

Table 7-8 Digital I/O checks .................................................................................................................................... 7-12

Table 7-9 Light pen checks ...................................................................................................................................... 7-13

Table 7-10 Master/slave checks ................................................................................................................................. 7-13

Table 7-11 Display board checks ............................................................................................................................... 7-14

8 Replaceable Parts

Table 8-1 Digital board assembly .............................................................................................................................. 8-2

Table 8-2 Display board assembly ............................................................................................................................. 8-3

Table 8-3 Backplane assembly ................................................................................................................................... 8-3

Table 8-4 Voltage regulator assembly ....................................................................................................................... 8-3

Table 8-5 Chassis assembly ....................................................................................................................................... 8-4

Table 8-6 Miscellaneous ............................................................................................................................................ 8-4

B

Table B-1 IEEE-488 bus command summary ............................................................................................................ B-4

Table B-2 Hexadecimal and decimal command codes ............................................................................................... B-5

Table B-3 Typical addressed command sequence ...................................................................................................... B-7

Table B-4 Typical common command sequence ........................................................................................................ B-7

Table B-5 IEEE command groups .............................................................................................................................. B-7

Table B-6 Model 707A interface function codes ........................................................................................................ B-8

xii

1

General Information

1.1 Introduction

This section contains general information about the Model
707A Switching Matrix. The Model 707A is designed as a
programmable switch for connecting signal paths in a matrix
topology. It is for applications requiring a large-scale matrix
(up to 576 crosspoints per mainframe and 2880 crosspoints
per master/slave configuration). Plug-in cards are available
for general and special purpose switching applications.

Section 1 is arranged as follows:

1.2 Features

1.3 Warranty Information

1.4 Manual Addenda

1.5 Safety Symbols and Terms

1.6 Specifications

1.7 Unpacking and Inspection

1.8 Repacking for Shipment

1.9 Optional Accessories

1.2 Features

• An active front panel LED display shows the current
relay status, a stored setup, or an editing scratchpad.

• High-speed triggering of stored setups.

• Make/break and break/make switching are programma­ble by rows. Operation is transparent to the user and
independent of the relay setup.

• With five units connected in a master/slave configura­tion, the maximum matrix size is eight rows by 360 col­umns (2880 crosspoints on one IEEE-488 address).

• An optional light pen is available for interactive con­trolling of relay states, editing stored relay setups, and
selecting make/break and break/make rows.

1.3 W arranty information

Warranty information is located at the front of this instruc­tion manual. Should your Model 707A require warranty ser­vice, contact the Keithley representativ e or authorized repair
facility in your area for further information. When returning
the mainframe for repair be sure to fill out and include the
service form at the back of this manual to provide the repair
facility with the necessary information.

Key features of the Model 707A Switching Matrix include:

• The six-slot mainframe accepts any mix of 8-row by
12-column matrix cards.

• Rows are extended within the mainframe to minimize
system wiring and interconnect requirements.

• Storage of 100 sets of relay setups, which can be
uploaded or downloaded through the IEEE-488 inter­face.

1.4 Manual addenda

Any improvements or changes concerning the mainframe or
manual will be explained in an addendum included with the
unit. Be sure to note these changes and incorporate them into
the manual before using or servicing the unit.

1-1

General Information

1.5 Safety symbols and terms

The following symbols and terms may be found on an instru­ment or used in this manual:

!

The
should refer to the operating instructions located in the
instruction manual.

The
may be present on the terminal(s). Use standard safety pre­cautions to avoid personal contact with these voltages.

The WARNING heading used in this manual explains dan­gers that could result in personal injury or death. Alw ays read
the associated information very carefully before performing
the indicated procedure.

The CAUTION heading used in this manual explains haz­ards that could damage the instrument. Such damage might
invalidate the warranty.

symbol on an instrument indicates that the user

symbol on an instrument shows that high voltage

1.6 Specifications

Model 707A specifications can be found at the front of this
manual. These specifications are exclusiv e of the matrix card
specifications, which are located in their appropriate instruc­tion manual.

1.7 Unpacking and inspection

1.7.1 Inspection for damage

Upon receiving the Model 707A, carefully unpack it from its
shipping carton and inspect the unit for any obvious signs of
physical damage. Report any damage to the shipping agent
immediately. Save the original packing carton for possible
future reshipment.

1.7.2 Shipment contents

The following items are included with every Model 707A
order:

• Model 707A Switching Matrix

• Model 707A Instruction Manual

• Power line cord

• Relay test connector

• Fixed rack mounting hardware

• Additional accessories as ordered

1.8 Repacking for shipment

Should it become necessary to return the Model 707A for
repair, carefully pack the unit in its original packing carton
or the equivalent, and include the following information:

• Call the repair department at 1-800-552-1115 for a
Repair Authorization (RMA) number.

• Advise as to the warranty status of the mainframe.

• Write ATTENTION REPAIR DEPARTMENT and the
RMA number on the shipping label.

• Fill out and include the service form located at the back
of this manual.

1.9 Optional accessories

The following accessories are av ailable for the Model 707A:
Model 7070 Universal Adapter Card — The Model 7070

card installs in the Model 707A and is jumper-selectable for
use either as a backplane extender or a breadboard. It has
quick disconnect screw terminals and 10-ft. ribbon cables.

Model 7071 General Purpose Matrix Card — The Model
7071 card has 8 rows by 12 columns of 3-pole Form A
switching for general purpose applications. It installs in the
Model 707A and has mass terminated connectors in addition
to quick-disconnect screw terminals.

Model 7071-4 General Purpose Matrix Card — The Model
7071-4 card has dual 4 rows by 12 columns of 3-pole Form
A, which is also configurable as 8 rows by 12 columns of 3­pole Form A or 4 rows by 24 columns of 3-pole Form A. It
installs in the Model 707A and has 38 pin quick disconnect
connectors.

Model 7072 Semiconductor Matrix Card — The Model 7072
card has 2 rows by 12 columns of 2-pole Form A for lo w cur­rent switching, 4 rows by 12 columns of 2-pole Form A for
general purpose switching, and 2 rows by12 columns of
1-pole Form A for C-V switching. It installs in the Model
707A and has 3-lug triaxial connectors.

Model 7072-HV Semiconductor Matrix Card — The Model
7072-HV card has 2 rows by 12 columns of 2-pole Form A
for low current paths to jumpers, 4 rows by 12 columns of 2­pole Form A for general purpose paths to the backplane, and
2 rows by 12 columns of 1-pole Form A for C-V paths to
jumpers. It installs in the Model 707A and has 3-lug triaxial
connectors.

1-2

General Information

Model 7073 Coaxial Matrix Card — The Model 7073 card
has 8 rows by 12 columns of 1-pole Form A switching (up to
30MHz) for applications with single-ended instruments. It
installs in the Model 707A and has BNC connectors.

Model 7074-D General Purpose Multiplexer Card — The
Model 7074-D card has eight banks of 1 row by 12 columns
of 3-pole Form A. Adjacent banks can be connected together
or jumpers can be removed to isolate any bank from the
backplane. It installs in the Model 707A and has four 75 pin
bank connections and one 38 pin connector for row connec­tions.

Model 7075 2-Pole Multiplexer Card — The Model 7075
card has eight banks of 1 row by 12 columns of 2-pole Form
A. Adjacent banks can be connected together or jumpers can
be removed to isolate any bank from the backplane. It installs
in the Model 707A and has nine 25 pin subminiature D con­nectors, eight for bank connections and one for row connec­tion.

Model 7076 Dual 2-Pole Matrix Card — The Model 7076
card has dual 4 rows by 12 columns of 2-pole Form A, which
is also configurable as 8 rows by 12 columns of 2-pole Form
A. Jumpers can be removed to isolate any bank from the
backplane. It installs in the Model 707A and has three 25 pin
subminiature D connectors, two for column connection and
one for row connection.

Model 7077 Isolated Coaxial Matrix Card — The Model
7077 card has 8 rows by 12 columns of 2-pole Form A. It
installs in the Model 707A and has BNC connectors.

Model 7078-DIN 8-pin DIN Cable — The Model 7078-DIN
cable has two 8-pin circular (DIN) connectors and is 1.8m (6
ft.) long. Multiple cables are used for connecting Model
707A units in a master/slave configuration through the rear
panel master/slave connectors.

Model 7078-PEN Programming Light Pen — The Model
7078-PEN connects to the Model 707A front panel. It is used
to toggle the states of crosspoint LEDs, make/break LEDs,
and break/make LEDs. A pen holder is included.

Model 7079 Slide Rack Mounting Kit — The Model 7079
kit consists of two sets of support brackets, equipment slides,
and hardware for mounting the Model 707A in a standard
19-inch equipment rack or cabinet.

Model 7007 Shielded IEEE-488 Cables — The Model 7007
connects the Model 707A to the IEEE-488 bus using
shielded cables to reduce electromagnetic interference
(EMI). The Model 7007-1 is one meter (3.3 ft.) long and has
an EMI shielded IEEE-488 connector at each end. The
Model 7007-2 cable is identical to the Model 7007-1, but is
2m (6.6 ft.) long.

Model 7051 BNC to BNC Cables — The Model 7051 cables
are for making connections to External Trigger and Matrix
Ready on the Model 707A rear panel. The Model 7051-2 is
a 50 Ω BNC to BNC cable (RG-58C), which is 0.6m (2 ft.)
long. The Model 7051-5 cable is identical to the Model
7051-2, but is 1.5m (5 ft.) long.

Model 7172 Low Current Matrix Card — The Model 7172
card has 8 rows by 12 columns of 2-pole Form A. Expanding
the columns can be done internally by connecting the rows
of multiple 7172 cards together with coax jumpers. It installs
in the Model 707A and has 3-lug triaxial connectors.

Model 7173-50 High Frequency 2-Pole Matrix Card — The
Model 7173-50 card has 4 rows by 12 columns of 2-pole
Form C with row isolators. It installs in the Model 707A and
has BNC connectors.

Model 7174A Low Current Matrix Card — The Model
7174A card has 8 rows by 12 columns of 2-pole Form A.
Expanding the columns can be done internally by connecting
the rows of multiple 7174A cards together with coax jump­ers. It installs in the Model 707A and has 3-lug triaxial con­nectors.

Model 8000-14 Enclosures — The Model 8000-14 is a
19”-wide by 14”-high open-backed steel enclosure. It is sup­plied with hardware to mount a bench-top Model 707A The
top cover of the enclosure can be removed to access jumpers
between cards installed in a Model 707A.

1-3

2

Card Installation

2.1 Installing and removing cards

Before operating the Model 707A in a test environment,
matrix cards (up to six per mainframe) must be installed into
the mainframe. Note that matrix cards are not necessary to
program setups. Setups for master/slave configurations can
be programmed as long as the MASTER/SLAVE OUT to
MASTER/SLAVE IN loop connections are present. (See
paragraph 3.5.2.)

WARNING

Before installing/removing cards or
making card connections, turn off main­frame power and disconnect the line
cord. Also, ensure that no power is
applied from the user's circuit.

Install a card in the Model 707A as follows, using Figure 2-1
as a guide. Instructions specific to each card can be found in
the appropriate card manual.

CAUTION

Do not touch the card surfaces, connec­tors, or components to avoid contamina­tion that could degrade card
performance.

2. Remove the slot cover from the desired slot.

3.

With one hand grasping the card's handle, and the other
supporting its weight, line up the card with the card
guides in the slot. Ensure that the component side is fac­ing the fan of the mainframe.

4. Slide the card into the mainframe until it is fully seated
in the backplane connectors. Finger-tighten the spring­loaded mounting screws at the back of the card to lock
it in place.

WARNING

The mounting screws must be secured to
ensure a proper chassis ground connec­tion between the card and the main­frame. Failure to properly secure this
ground connection may result in per­sonal injury or death due to electric
shock.

NOTE

Some cards have connectors that are inac­cessible once the card is fully inserted into
the mainframe (e.g., the quick disconnect
terminal blocks on Model 7071 cards). In
these cases, connect wires to the row and
column terminal blocks before seating it in
the backplane connectors.

1. Ensure that the access door on top of the mainframe is
fully closed and locked down. (The bottom side of the
access door has card guides.)

2-1

Card Installation

NOTE

The SMB coax jumpers used between
Model 7072 cards do not have to be
installed before the cards are inserted. Use
the access door on top of the mainframe
for this purpose. (Because of the access
door, the Model 7079 slide rack kit is rec­ommended for rack-mounted units.)

5. To remove a matrix card, first turn off the mainframe
and disconnect the line cord. Ensure no voltage is
applied from the user's circuit. Remove any internal
cabling between cards through the unit's access door.
Loosen the spring-loaded mounting screws and pull out
the card by its handle.

Figure 2-1

Installing a matrix card

2-2

3

Getting Started

3.1 Introduction

This section contains introductory information on operating
your instrument and is intended to help you get your Model
707A up and running as quickly as possible. It includes a
brief description of operating controls and connections.
Once you are familiar with the material presented here, refer
to Section 4 for more detailed information.

Section 3 is organized as follows:

3.2 Front Panel Familiarization: Briefly describes each

front panel control and outlines display operations.

3.3 Rear Panel Familiarization: Outlines each aspect of

the Model 707A rear panel, including connectors.

3.4 Card Connectors: Describes where to connect instru-

ments and DUTs to the matrix rows and columns.

3.5 Expanding Matrix Size: Discusses methods for

expanding the matrix, both internal to the mainframe
and with multiple units.

3.6 Basic Switching Operation: Provides a general proce-

dure for powering up the Model 707A, choosing make/
break or break/make operation, modifying the cross­point display, storing the setup, and sending the setup to
the relays.

3.2 Front panel familiarization

An overview of the Model 707A operation is gi ven in the fol­lowing paragraphs. The front panel of the instrument is
shown in Figure 3-1. Figure 3-2 illustrates setup data trans­fers within the Model 707A. This pictorial will be helpful in
understanding the operations of individual front panel keys.

All front panel keys except POWER are momentary contact
switches. Some keys have an LED to indicate the selected
function. The keys are color coded into functional groups for
ease of operation.

3-1

Getting Started

Figure 3-1

Model 707A front panel

3-2

Getting Started

Model 707A
Internal
Memory

Stored
Setup #100

Stor ed
Setup #1

Crosspoint Relays

Model 7X7X
Matrix Cards

Model 707A
Front Panel

Crosspoint Display

Figure 3-2

Setup data transfers

3-3

Getting Started

POWER — AC power switch turns the unit on or off.

Crosspoint display group

MEMORY — Displays a stored relay setup (from location

shown in MEMORY STEP field) on the crosspoint display
and lights the MEMORY indicator.

RELAYS — Displays the current relay setup on the cross-

point display and lights the RELAYS indicator.

CROSSPOINT DISPLAY MODIFIED — Lights when

changes are made to the crosspoint display (by front panel
keys or light pen), making it different from the original
configuration.

COPY DISPLAY → MEMORY — Copies the displayed

cross-point configuration to the location shown in the MEM­ORY STEP field.

COPY DISPLAY → RELAYS — Copies the displayed

cross-point configuration to the relays.

AUTOMATIC (COPY DISPLAY → RELAYS) — When

this LED is lit, any change to the crosspoint display is sent to
the relays at the same time. The pushbutton toggles the LED
on and off .

DELETE — Deletes the setup at the location shown in the

MEMORY STEP field. Moves higher stored setups down
one memory location.

MENU — Steps through the available menu items.

• View digital input, program digital output.

• Select whether rising or falling edge of External Trigger
pulse triggers Model 707A.

• Select an active high or active low Matrix ready output
signal.

• Select master/slave or stand-alone operation.

• Program IEEE-488 address.

• View longest relay setting time of present card
configuration.

• Vie w unit configuration by slot number and card model
number.

• Execute self-test.

• Restore factory defaults (and clear stored setups).

Programmable parameters can be changed with the
SCROLL or data entry keys and then pressing enter.

Switching group

Scroll group

SCROLL — If MEMORY indicator is lit, increments

MEMORY STEP field and displays setup on crosspoint
LEDs. If RELAYS indicator is lit, increments RELAY STEP
field, displays setup on crosspoint LEDs, and sends setup to
relays. Also used for scrolling up through a list of multiple
choice parameters.

SCROLL — Same actions as the SCROLL key

except that it increments and scrolls down.

Memory group

INSERT — Inserts a blank setup at the location shown in

the MEMORY STEP field. Moves higher stored setups up
one memory location.

SETTLING TIME — Displays the current value of pro-

grammed settling time. (This delay begins after the relay set­tling time.) T o change the v alue, enter between 0-65000msec
and press ENTER.

MAKE/BREAK — Selects rows to operate as make/break

(make-before-break) for all setups. First enter row designa­tion (A-H), then press MAKE/BREAK to toggle the state for
that row and immediately reprogram the Model 707A for the
new operation.

BREAK/MAKE — Same action as MAKE/BREAK except

that it selects break/make (break-before-make) rows.
(Selecting a row for break/make de-selects it for make/break
and vice versa.)

LOCAL — When in remote (REMOTE on), returns the

Model 707A to local mode (REMOTE off). It restores oper­ation of other front panel controls unless LLO (Local Lock­out) is in effect.

3-4

Getting Started

Trigger group

ENABLE — Toggles between triggers enabled and triggers

disabled. When triggers are enabled, the LED is lit.

SOURCE — Displays current trigger source. Use SCROLL

keys to display sources, then press ENTER to select the
desired source:

TRIG ON TALK - IEEE talk command
TRIG ON GET - IEEE GET command
TRIG ON X - IEEE X command
TRIG ON EXT - External trigger pulse (rear panel

input)

TRIG ON KEY - Front panel MANUAL key only

MANUAL — Generates a trigger from front panel if trig-

gers are enabled (no matter which trigger source is selected).
If the trigger source is TRIG ON KEY, only the MANUAL
key generates a trigger.

DATA ENTRY (A-H, 0-9) — These keys are for entering

row/column addresses and setup locations, selecting make/
break and break/make rows, and entering various numeric
values.

CANCEL — If the value in the alphanumeric display has

been modified, this key restores the current parameter value.
If the value in the alphanumeric display has not been modi­fied, this key returns the Model 707A to the previous display.
CANCEL also exits from menu mode if no changes have
been made.

ENTER — If the value in the alphanumeric display has been

modified, pressing this key stores the parameter value. Also
invokes immediate action items from the menu and exits
menu mode (except when digital I/O is displayed).

CLOSE — Same action as OPEN key except that it turns on

the crosspoint LED and relay.

ALPHANUMERIC DISPLAY — A 14-character display

that can show:

• Error messages.

• Menu item selections.

• Last setup sent from memory to the relays (RELAY
STEP field).

• Last setup recalled from memory to the crosspoint dis­play (MEMORY STEP field).

• Trigger source.

• Programmed settling time.

• Alphanumeric key presses (row/column addresses,
setup locations).

IEEE-488 status indicators

T ALK, LISTEN, REMOTE — These three LED indicators

apply to instrument operation over the IEEE-488 bus. The
TALK and LISTEN indicators show when the unit has been
addressed to talk or listen. REMOTE turns on to show when
the unit is in the IEEE-488 remote state. See Section 4 for
detailed information on operation over the bus.

CROSSPOINT DISPLAY LEDs — Show open and closed

crosspoints of the current relay setup, a stored relay setup, or
an edited relay setup. Each LED block of 8 rows by 12 col­umns shows on/off states of one card. States can be changed
by front panel keys, triggers, or optional light pen. Cross­point configurations can be stored in memory or sent to
relays.

RESET — Performs the same functions as cycling power

(all relays are opened, triggers are disabled, RELA Y STEP to
000, MEMORY STEP to 001, etc.), except powerup self­checking and master/slave loop initialization.

CLEAR — Turns off all crosspoint display LEDs. If the

AUTOMATIC (COPY DISPLAY → RELAYS) indicator is
lit, all relays are opened immediately.

OPEN — Turns off crosspoint LED of row/column shown

on alphanumeric display. If the AUTOMATIC (COPY DIS­PLAY → RELAYS) indicator is lit, the corresponding relay
opens immediately.

MAKE/BREAK ROW LEDs — Show which rows are

selected for make/break operation. The LEDs can be turned
on or off by the MAKE/BREAK, BREAK/MAKE keys or by
an optional light pen.

BREAK/MAKE ROW LEDs — Same function as MAKE/

BREAK row LEDs except for showing which rows are
selected for break/make operation. Note that selecting a row
for break/make de-selects it for make/break and vice versa.

LIGHT PEN — An optional input device for toggling the

on/off state of the Crosspoint Display LEDs, MAKE/
BREAK row LEDs, and BREAK/MAKE row LEDs. One
light pen is used. to control the LEDs of up to five Model
707A mainframes.

3-5

Getting Started

3.3 Rear panel familiarization

An overview of the rear panel of the Model 707A is in the
paragraphs that follow. The rear panel is shown in Figure
3-3. In addition to the various connectors, a column locator
diagram for a master or stand-alone unit is provided on the
rear panel.

CARD SLOTS — The Model 707A accepts up to six plug-

in matrix cards (8 rows by 12 columns) per mainframe.

MASTER/SLAVE OUT — An 8-pin DIN connector for

connecting a cable to the next mainframe in a master/slave
daisy chain configuration.

MASTER/SLAVE IN — An 8-pin DIN connector for con-

necting a cable from the previous mainframe in a master/
slave daisy chain configuration.

EXTERNAL TRIGGER INPUT — A BNC jack for

applying a trigger pulse to change to the next relay setup, if
triggers are enabled and TRIG ON EXT is selected as the
source. Pulses must be TTL-compatible, negative-or
positive-going (selected by a menu item), with a duration
greater than 600nsec.

RELAY TEST — A 6-pin quick-disconnect terminal block

with logic ground and four logic inputs for testing cross­point relay closures. W iring between this terminal block and
rows A and B of an y card in the group of cards to be tested is
necessary for the test.

DIGIT AL I/O — A DB-25 connector for the TTL-compati-

ble digital I/O with data lines for eight inputs and eight out­puts. It also contains control lines for handshaking (Input
Latch and Output Strobe). Input lines are viewed and output
lines are programmed through a menu item.

IEEE-488 INTERFACE — This connector interfaces the

Model 707A to the IEEE-488 bus. IEEE interface function
codes are marked adjacent to the connector.

AC RECEPTACLE — Power is applied through the sup-

plied power cord to the 3-terminal AC receptacle.

LINE FUSE — The line fuse provides protection for the A C

power line input. The fuse rating must match the line voltage
setting.

F AN FILTER — The fan filter keeps dirt from being drawn

into the instrument by the internal cooling fan. The filter
should be kept clean to ensure proper instrument cooling.

MATRIX READY OUTPUT — A BNC jack providing a

TTL-compatible, high- or low-true level (selected by a menu
item). It goes false when relays are switched and goes true
after the sum of the relay setting time and the programmed
settling time.

3-6

Getting Started

Figure 3-3

Model 707A rear panel

3-7

Getting Started

3.4 Card connections

Each card designed for the Model 707A is configured as an
8-row by 12-column matrix. The rows are lengthened by
adding columns from other cards (of the same model num­ber). Connections for row expansion are usually internal to
the mainframe, either through the analog backplane buses or
with user-installed jumpers, depending on the card model.
Rows can also be expanded across mainframe boundaries,
either in a master/slave or stand-alone/stand-alone configu­ration. In a master/slave configuration of up to five main­frames, the rows are extended to 360 columns maximum.
(Paragraph 3.5 describes master/slave expansion.)

Expansion of rows leads to a long, narrow matrix. If your
application requires few instruments and many DUTs, con­nect the instruments to rows (up to 8) and the DUTs to col­umns (up to 72 with 6 cards). This connection scheme is
optimum because the row-column path has only one cross­point, as shown in Figure 3-4.

DUT

Source

Source

Measure

A

B

C

Selecting the row connections for instruments is important
with cards designed for multiple applications. Using the
Model 7072 as an example, the recommended connections
are as follows:

• Rows A and B (1ow current) — Picoammeters,
electrometers.

• Rows C through F (general purpose) — DMMs,
sources.

• Rows G and H (C-V characteristics) — C-V analyzers.

An alternate connection scheme of the long, narrow matrix
has all connections on the columns, both instruments and
DUTs. This is done when the series of tests requires a large
number of instruments and DUTs, with only a few signals for
each test. As seen in Figure 3-5, with two cards, two cross­point relays must be closed to complete a path from column­column (a safety benefit when sourcing). Paths with multiple
crosspoints have additional path resistance and contact
potential than single crosspoint paths.

Crosspoint programming becomes more complex with
column-column paths because of the number of possible
paths for large matrices and the choice of rows to complete
the path. (See Table 3-1.)

Measure

123456789101112

Note : One cr os s point closur e y ields a r ow- c olum n path.

Figure 3-4

Connecting instruments to rows

D

E

The row completion choice for column-column paths on
multiple application cards follows the recommendations

F

G

H

given previously for row-column paths. That is, with a
Model 7072 card, close a crosspoint relay in row A or B for
low current applications, row C, D, E, or F for general pur­pose switching, and row F or G for C-V switching.

3-8

Getting Started

DUT Test

Fixture

Instrumentation

Note: BNC matrix cards shown. Other card connections similar.

BNC cables connect to row terminals
of both cards.

(14 connections)

1 2 3 4 5 6 7 8 9 10 11 12

Master

DUTs

Simplified

Equivalent Circuit

1 2 3 4 5 6 7 8 9 10 11 12

Slave

BNC Cable - Columns

Ribbon Cable - Rows

Instrumentation

(10 connections)

A
B
C
D
E
F
G
H

Figure 3-5

Connecting instruments to columns

Table 3-1

Row-column and column-column paths

Connection scheme Crosspoints per path

Possible paths for
8 rows by 12 columns

Possible paths for
8 rows by 72 columns

Row-column 1 96 576
Column-column 2 66 2556

Notes:

1. The crosspoints per path do not take into account any isolator relays that may be present on a card.

2. Each column-column path can be through one of eight rows (e.g., connect column 1 to column 2 by closing A1 and A2,
or close B1 and B2, etc.)

3-9

Getting Started

3.5 Expanding matrix size

The 8-row by 12-column matrix cards of the Model 707A
mainframe are building blocks for larger matrices. Matrix
expansion is accomplished by two methods:

• Internal to the mainframe — The Model 707A back­plane automatically extends rows from other like cards.
Special purpose rows (not extended by the backplane)
are extended by user-installed jumpers between adja­cent cards.

• External to the mainframe — A master/slave connec­tion of up to five mainframes is an extension of the rows
(up to 8 rows by 360 columns). Also, individual rows
and columns can be connected between cards or
between mainframes.

The paragraphs that follow explain matrix expansion in
detail.

3.5.1 Single unit expansion

Expansions to a single unit are either connections internal to
the mainframe or external connections of the cards in the
same mainframe.

The third analog bus expands eight rows of a signal HI path
and a common ground (chassis). The common ground sur­rounds the HI path and separates adjacent rows, as shown in
Figure 3-9. These rows are for 1-pole switching in common
ground (high frequency) systems or floating signals (with an
additional row for switching low).

J101 J106

Analog Bus #1

J101 - J106, Pins 1 - 22
4 Rows - HI and LO

Analog Bus #2

J101 - J106, Pins 23 - 86
8 Rows - HI, LO, Guard

Analog
Buses

Internal expansion and isolation

Internal expansion is done automatically through the Model
707A backplane. Each of the six mainframe slots has three
card edge connectors, as shown in Figure 3-6 and described
below:

• Upper connectors (J101-J106) — Consists of two ana­log buses (pins 1-22 and pins 23-86) to expand card
rows.

• Middle connectors (J107-J112, 34-pin connectors) —
Consists of a third analog bus to expand card rows.

• Lower connectors (J113-J118, 30-pin connectors) —
This is a digital bus for mainframe control of the matrix
cards.

The first analog bus expands signals HI and LO of four
rows. The LO of an indi vidual row surrounds the HI path and
is between the adjacent rows, as shown in Figure 3-7. These
rows are used for 2-pole, general purpose switching.

The second analog bus expands signals HI, LO, and
GUARD of eight rows. The GUARD of each row surrounds
the HI and LO paths and separates adjacent rows. See Figure
3-8. These rows are used for 3-pole, general purpose switch­ing and when the guard signal needs to be switched.

Digital
Bus

Slot 1 Slots 2 - 5 Slot 6

Figure 3-6

Backplane buses

J107

Analog Bus #3

J107 - J112, Pins 1 - 34
8 Rows - HI , and Chassis Ground

J113 J118

J113 - J118, Pins 1 - 30

J112

3-10

F

B

Getting Started

1HI

Row

Row

Row

Row

LO
LO

HI
LO
LO

HI
LO

LO

HI
LO 21

igure 3-7

ackplane expansion of analog bus #1

212 12HI

LO
LO

HI

LO

J101 J102 J106

Slot 1 Slot 2 Slot 6Slots 3 - 5

LO

HI
LO
LO

HI
LO

2122 22

2HI

LO
LO

HI
LO
LO

HI
LO
LO

HI
LO22

J103 - J105

22

HI
LO
LO
HI
LO
LO
HI
LO
LO
HI
LO21

3-11

Getting Started

Row

Row

Row

Row

Row

Row

Row

Row

Guard

HI
LO

Guard
Guard

HI
LO

Guard
Guard

HI
LO

Guard
Guard

HI
LO

Guard
Guard

HI
LO

Guard
Guard

HI
LO

Guard
Guard

HI
LO

Guard
Guard

HI
LO

Guard

86

Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard

85

23 24 23 24

J101 J102 J106J103 - J 105

85

86

Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard

23 24

85

86

Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard
Guard

HI

LO

Guard

Slot 1 Slot 2 Slot 6Slots 3 - 5

Figure 3-8

Backplane expansion of analog bus #2

3-12

Getting Started

Row

Row

Row

Row

Row

Row

Row

Row

1

HI

HI

HI

HI

HI

HI

HI

HI

33 34 33 34 33 34

Chassis

212 12

HI

HI

HI

HI

J107 J108 J109 - J111

Slot 1 Slot 6

HI

HI

HI

HI

Slot 2

2

HI

HI

HI

HI

HI

HI

HI

HI

Slots 3 - 5

J112

HI

HI

HI

HI

HI

HI

HI

HI

igure 3-9

ackplane expansion of analog bus #3

Matrix cards for use in the Model 707A have different edge
connectors, depending on the signal path configuration of
each card model. The multiplexer cards are summarized in
Table 3-2. All cards have a connector for the digital bus.

Note that rows A, B, C, and H of Model 7072 cards, for
example, are expanded with SMB coax jumpers between
adjacent cards to lessen signal losses of the low current and
C-V rows. The jumpers are internal to the mainframe.

When a mainframe contains different card models, instru­ments must be connected to each card type because of the
differing analog bus usage. An example of this is shown in
Figure 3-10.

Table 3-2

Matrix and multiplexer cards

Card family Model Form

Universal 7070 96 Open Collector Drivers
General

purpose

Semiconductor 7072

Coaxial 7073

7071
7071-4
7074-D
7074-M
7075
7076

7072-HV
7172
7174

7077
7173-50

8 × 12 Matrix
Dual 4 × 12 Matrix Card
Eight 1 × 12 Multiplexer Card
Eight 1 × 12 Multiplexer Card
Eight 1 × 12 Multiplexer Card
Dual 4 × 12 Matrix Card

8 × 12 Matrix Card
8 × 12 Matrix Card
8 × 12 Matrix Card
8 × 12 Matrix Card

8 × 12 Matrix Card
8 × 12 Matrix Card
4× 12 Matrix Card

3-13

Getting Started

External
Row
Connec­ tions

Devices Under Test

11213242536374849606172

A

H

7071

Slot 1

Internal
Row
Connec­ tions

A

7071
Slot 2

H

A

H

7072
Slot 3

Internal
Row
Connec­ tions

A

7072
Slot 4

H

A

H

7073

Slot 5

Internal
Row
Connec­ tions

A

7073
Slot 6

H

Instruments

External
Row
Connections

Figure 3-10

Row connection examples

In addition to expanding rows in a mainframe, it is also pos­sible to isolate card rows to some extent. There are factory­installed jumpers on the backplane that can be removed to
separate the general purpose rows. These jumpers, which are
behind the Model 707A front panel, are between slots 3 and
4 of analog bus #1 and analog bus #2. Removing these jump­ers effectively separates the mainframe into tw o 3-slot units.
(Jumper removal is described in paragraph 7.6.)

Another isolation method is simply to disconnect the SMB
coax jumpers between adjacent Model 7072 cards, for exam­ple. These jumpers (for rows A, B, G, and H) are accessed
through a door on top of the mainframe.

As an example, jumpers on the Model 7073 card let you
selectively expand ro ws on the backplane to slots on either or
both sides, or completely isolate rows from the backplane.

External expansion

External expansion within a single mainframe is possible
with user-installed wiring between rows and columns of like
cards. The available accessory cables for external connec­tions are listed in Table 3-3.

External
Row
Connections

CAUTION

Connecting dissimilar cards together
often degrades performance of both
cards. For example, connecting a Model
7072 to a Model 7073 would degrade
low current switching on the 7072 and
high frequency switching done with the

7073.

An example of external expansion uses the mainframe as one
6-slot unit and, for some applications, as two 3-slot units.
After removing the backplane jumpers, just use external row
jumpers between the cards in slots 3 and 4 to select the
desired configuration.

External expansion of the cards can also be used to imple­ment a partial matrix. As shown in Figure 3-11 for Model
7071 cards, a column connection is made between the two
isolated general purpose backplanes. With the example con­nections shown, three crosspoints must be closed to source
(increasing the safety factor), but only one cross-point clo­sure is needed to measure (recommended for sensitive
instruments).

3-14

Table 3-3

Model 707A external expansion cables

Model no. Description Expansion

Getting Started

7078-KIT
7078-MTC

7078-TRX-3
7078-TRX-10

7051-2
7051-5

7074-KIT
7074-MTC

Mass Terminated Cable Kit
Mass Terminated Cable (20 ft.)

3-lug Triax-Triax Cable (3 ft.)
3-lug Triax-Triax Cable (10 ft.)

BNC-BNC Cable (2 ft.)
BNC-BNC Cable (5 ft.)

Mass Terminated Cable Kit
Mass Terminated Cable (20 ft.)

7075-MTC Mass Terminated Cable (10 ft.) 7075, 7076 rows/columns

External Columns
(DUT's)

112

Backplane Row
Expansion Cable

A

7071

Model 707A
Unit 1

H

External Columns
(DUT's)

13 24

7071

Model 707A
Unit 2

Backplane Row
Expansion Cable

A

H

7071, 7071-4 rows/columns,
7074 rows

7072, 7072-HV, 7172, 7174
rows/columns

7073, 7173-50 rows/columns

7074 banks

A

7071

Model 707A
Unit 3

H

Ext er nal Rows
( Measur e)

Figure 3-11

Example of partial matrix expansion

External
Columns

7071

Model 707A
Unit 4

A

H

Ext er nal Rows
(Source)

3-15

Getting Started

3.5.2 Multiple unit expansion

Analog expansion

One method to expand a matrix across mainframe bound­aries is to connect cards of separate stand-alone units, either
by rows or columns. Each unit has a different IEEE-488 bus
address and is programmed independently. The additional
digital I/O ports are available for programming.

The analog backplane buses can be expanded between sepa­rate mainframes. As seen in Figure 3-12, a mass terminated
cable can be used to extend Model 7071 card rows (J101­J106, pins 23-86). This configuration of two stand-alone
units is an 8-row by 144-column general purpose matrix,
with each mainframe programmed independently.

As an example of expansion by columns, consider a 16-row
by 72-column matrix of Model 7072 cards. This can be done
by connecting all columns of card #1 in one unit to all col­umns of card #1 in another unit, and so on for all cards.
(Triax T-adapters are used in this example to connect instru­ments or devices to the columns.)

Analog expansion and control expansion

Another method of expanding a matrix with multiple main­frames is to connect up to five units in a master/slave config­uration. This is done by connecting the rows of like cards in

separate units, as shown previously in Figure 3-12, but also
by connecting the units in a closed loop of DIN cables for
communication and control. A master/slave system configu­ration appears as one unit with expanded card capacity. That
is, only the master unit is addressed by the IEEE-488 bus
controller.

A master/slave configuration extends matrix rows yielding a
long, narrow matrix. Figure 3-13 shows the connections
between two units having Model 7071 cards. With five units,
the maximum matrix size is 8 rows by 360 columns. Figure
3-14 shows the column assignments for the maximum con­figuration.

If the mainframes of a master/slave configuration contain
different card models, group like cards as much as possible.
This will reduce the need to extend the analog buses with
external cables.

In some cases, external row expansion is not necessary at all
(e.g., one unit only with Model 7071 cards, the second unit
only with Model 7072 cards).

The example of Figure 3-15 shows the row expansion, but
not the closed loop of DIN cables for master/slave
communication and control. The figure shown is actually
three matrices (one 8-row by 72-column and two 8-row by
144-column) that are programmed as one 8-row by 360-

column matrix.

Columns

Rows

112

A

7071

Slot 1

H

61 72

7071

Slot 6

igure 3-12

odel 7071 row connections of stand-alone units

Rows

Rows

Unit 1 Unit 2

Columns

112

7071
Slot 1

61 72

7071

Slot 6

A

Rows

H

3-16

Getting Started

Master
(Columns 1 - 72)

Rows

7071 7071 7071 7071 7071 7071

Cols.

1 2 3 4 5 6 1 2 3 4 5 6

To
Controller

Model 7007
IEEE Cable

igure 3-13

xample of master/slave interconnect cables

Mass Terminat ed Cable

M/S Out

M/S In

Slave 1
(Columns 73 - 144)

Rows

7071 7071 7071 7071 7071 70717071

Cols.

Model 7078 - DI N Cables

M/S Out
M/S In

3-17

Getting Started

Master

Sl ave 1

73-8485-96 97-

1 2 3 4 5 6

108

109­120

121­132

Sl ave 3

1-1213-2425-3637-4849-6061-

1 2 3 4 5 6

133­144

72

Sl ave 2

145-

157-

156

168

1 2 3 4 5 6

Sl ave 4

169­180

181­192

193­204

205­216

217-

229-

228

240

1 2 3 4 5 6

Figure 3-14

Master/slave column locations

3-18

241­252

253­264

265­276

277­288

289-

301-

313-

325-

300

312

324

336

337­348

1 2 3 4 5 6

349­360

Getting Started

H

Columns Columns

112

61 72

Instruments

Instruments

Instruments

A

H

External
Row
Connections

A

H

External
Row
Connections

A

H

External
Row
Connections

A

7071

Slot 1

Slots 2-5

Master Master

Internal
Row
Connections

7071

Slot 6

H

Master (8 Rows by 72 Columns)

Columns

73 84

7072

Slot 1

Slave 1 Slave 1 Slave 2 Slave 2

Slot 2- 5 Slot 2- 5

Internal
Row
Connections

Columns

133 144

A

7072

Slot 6

H

A

H

External
Row
Connections

Columns Columns

145 156

205 216

A

7072
Slot 1

H

Internal
Row
Connections

Slaves 1 and 2 ( 8 Rows by 144 Colum ns )

Columns

217 228

7073

Slot 1

Slot 2- 5 Slot 2-5

Slave 3 Slave 3 Slave 4 Slave 4

Internal
Row
Connections

Columns Columns Columns

227 228

A

7073

Slot 6

H

External
Row
Connections

289 300 349 360

A

A

7073
Slot 1

H

Internal
Row
Connections

H

7072

Slot 6

7073

Slot 6

Slaves 3 and 4 ( 8 Rows by 144 Colum ns )

igure 3-15

xample of master/slave row expansion

3-19

Getting Started

3.5.3 System expansion issues

Matrix expansion by Model 707A mainframes affects sys­tem specifications and speed. The extent depends on the size
and configuration of the switching system.

Within a mainframe, internal row e xpansion decreases isola­tion among like cards and increases offset current. Isolation
relays (on the Model 7072), backplane jumpers (for general
purpose rows), and SMB coax jumpers (on the Model 7072)
help lessen these effects.

Expansion of units along rows or columns also degrades the
isolation and offset current specifications because of the
number of parallel paths and relays on each signal line.

There are several issues that affect system speed, among
them are:

• Relay settling time — Each matrix card has a pre­defined relay settling time (for example 3msec for the
7071, 15msec for the 7072 and 7073). When card types
are mixed in a system, the longest settling time is in
effect.

• Bus communication — A master/slave setup responds
slower to bus commands because all communication is
through the master unit and the data transmission
among the units is verified with handshaking. Table 3-4
compares some typical times.

Table 3-4

Response time comparisons

Master with

Action Stand-alone

Respond to bus command
to close single relay

Download one setup to
707A

<15ms

60ms typical

4 slaves

<55ms

—

3.5.4 Documenting system configuration

With the connection flexibility of the matrix topology and
the expansion/isolation options of the Model 707A, it is
important to document the system configuration.

An example table for tracking card connections and expan­sion is shown in Table 3-5. Use the top portion of the table to
note system operation and size, the FROM/TO portion to list
card row and column connections, and the lower portion for
notes concerning expansion and operation (e.g., make/break
and break/make rows).

3-20

Getting Started

Table 3-5

Model 707A card configuration

Slot:___________________________________ Model:_______________________
Mainframe: Stand-alone _________
Master _____________ Slave 1_____________ Slave 2_____________ Slave 3 _____________ Slave 4 ___________

System size:

_______________________ rows __________ columns ___________ IEEE address ___________

FROM

(Instrument connection or DUT pin)

External Card

Connection

Row A

B
C
D
E
F
G
H

TO

(Instrument connection or DUT pin)

Expansion:

Notes:

Column 1

2
3
4
5
6
7
8
9
10
11
12

___ Backplane bus (rows through ribbon cable) ___ SMB coax jumpers (rows)
___ Point to point writing (rows/cols.) ___ Mass terminated cable (rows/cols.)
___ BNC coax cable (rows/cols.) ___ Triax cable (rows/cols.)

3-21

Getting Started

3.6 Basic switching operation

The following paragraphs will take you through a simple,
general, step-by-step procedure to edit a matrix setup, store
it in memory, and send the setup to the relays. Although the
steps are described with front panel operations, the proce­dure can be performed over the IEEE-488 bus. (An example
program showing this is given in paragraph 5.2.) Even with
no instruments or DUTs connected to the matrix cards, the
procedure will still have instructional benefits.

See Section 4 for more operation details including master/
slave configurations.

3.6.1 Power-up

Check that the instrument is set to correspond to the available
line voltage. The line voltage switch is located on the rear
panel. If the switch is set to the correct position, connect the
instrument to a grounded A C outlet using the supplied po wer
cable and turn on the unit.

CAUTION

If the switch setting does not correspond
to the available line power, do not
change the switch setting and power up
the unit as the line fuse will probably
blow. Instead, proceed to paragraph 7.2
for the line voltage selection procedure.

3.6.2 Selecting make/break and break/make rows

Select make-before-break, break-before-make, or don’t care
operation for the rows. The selections will be in ef fect for all
relay switching, even if a stored setup is not used. (As a gen­eral rule, use make/break operation for current sources and
break/make for voltage sources.)

Use the data entry keys to select a row, then press MAKE/
BREAK or BREAK/MAKE to toggle the state. (Selecting
one state for a row de-selects it for the other .) This operation
can also be performed with the light pen by using it to turn
on/off the MAKE/BREAK and BREAK/MAKE LEDs.

3.6.3 Modifying a relay setup

Perform the following steps to edit a matrix setup.

Step 1: Select a stored setup

If you want to modify setup #1, just press the MEMOR Y key .
The MEMORY indicator will light. To select another setup
(up to location 100), use the numeric data entry keys
(1eading zeros are not necessary), then press the MEMORY
key.

Step 2: Modify the displayed setup

Use the data entry keys to select a crosspoint address (Al
through H72), then press the OPEN or CLOSE key. Key­strokes will be shown on the alphanumeric display and the
CROSSPOINT DISPLAY MODIFIED indicator will light.

The Model 707A will perform a powerup self-test to check
ROM, RAM, card configuration, stored setups, master/slave
loop, indicators, and displays. It will then display the soft­ware revision level and IEEE-488 bus address.

When the self-test has completed, the Model 707A is config­ured with:

• All relays opened.

• RELA YS indicator lit (crosspoint display shows current
relay setup).

• RELAY STEP to 000 (a pseudo setup memory that is
cleared at powerup and sent to the relays).

• MEMORY STEP to 001.

Other powerup defaults are detailed in paragraph 4.3.

3-22

If you have the optional light pen, toggle the state of a
crosspoint LED by holding the light pen perpendicular to
and touching the front panel overlay and pressing the light
pen button.

Continue editing with the front panel keys or light pen until
the crosspoint display shows the desired configuration.

Getting Started

3.6.4 Storing setup and sending to relays

The following steps detail front panel operations necessary
to store and use the modified setup data.

Step 1: Storing setup in memory

To store the modified setup at the location shown in the
MEMORY STEP field, just press the COPY DISPLAY­MEMORY key. This action overwrites the old setup data at
that location with the newly modified setup.

T o select a dif ferent memory location, ke y in a valid location
number, then press the COPY DISPLAY-MEMORY key.
The MEMORY STEP field is set to the new location.

Step 2A: Sending setup to relays

To make the newly modified setup the current relay setup,
just press the COPY DISPLAY-RELAYS key. The relay
states will be changed to reflect the modified setup data. If
the MEMORY LED is lit, the RELAY STEP field will be set
equal to the MEMORY STEP field. In effect, this copies a
setup from memory to the relays.

Step 2B: Triggering setup to relays

If you modified setup #1 and restored it to memory at the
same location, a single trigger will copy the setup to the
relays. Do this by pressing the trigger SOURCE key, scroll­ing to the “TRIG ON KEY” display and pressing ENTER.
Then press the trigger ENABLE key. Pressing the trigger
MANUAL key will copy setup #1 to the relays and set the
RELAY STEP field to 001.

3-23

IEEE-488 Bus

Controller

Current

Relay Setup

100 Stor ed

Setups

Crosspoint

Display

Model 707
Controller

4

Operation

4.1 Introduction

This section contains a complete, detailed description of
each front and rear panel aspect of the Model 707A. The sec­tion is arranged as follows:

4.2 Setup Data Paths: Describes the paths for setup data

within a Model 707A and to/from a bus controller.

4.3 Power-up Procedure: Details how to connect the

instrument to line power and turn it on, including
power-up self-test and default conditions.

4.4 Displays and Messages: Covers the uses of the

alphanumeric display, crosspoint display, and make/
break and break/make row LEDs. Also lists display
messages that may be encountered during front panel
operations.

4.5 Selecting Crosspoint Display: Describes how to

select the source of relay setup data (current relay
setup or a stored setup).

4.6 Modifying Crosspoint Display: Discusses the opera-

tions to open/close crosspoint display LEDs.

4.7 Copying Crosspoint Display: Describes copying a

display to the relays and to memory.

4.8 Inserting and Deleting Stored Setups: Covers how

to insert a blank setup in memory and how to delete a
stored setup from memory.

4.9 Menu Operations: Details menu item selection and

operation, including digital I/O, external trigger,
matrix ready, master/slave, IEEE-488 bus address,
relay settling time, card identification, self-test, and
factory defaults.

4.10 Selecting Switching Parameters: Covers the pro-

grammed settling time and make/break, break/make
operations.

4.11 Triggering: Details selecting the trigger source and

describes the operation of the rear panel trigger input
and output jacks.

4.12 Resetting: Discusses the reset operation of the Model

707A.

4.2 Setup data paths

The design of the Model 707A is optimized for high speed
switching of relay setups for matrices with a maximum of 8
rows by 72 columns (one unit) to 8 rows by 360 columns
(five units). If no rows are selected for make/break or break/
make operation, previously stored setups can be switched to
the relays at a rate of up to 200 setups per second.

Besides the triggering of stored setup data to the relays, setup
data can be routed to/from the sources and destinations
shown in Figure 4-1. The data paths are selected by the front
panel or IEEE-488 bus operations listed in Table 4-1.

Figure 4-1

Paths for relay setup data

In addition to other front and rear panel operations, this sec­tion describes setup data transfers that are performed from
the Model 707A front panel. Section 5 will describe the bus
operations that transfer setup data.

4-1

Operation

Table 4-1

Setup data paths

Setup data path Action required

Display-Memory Display­Relays

Front panel keystroke Front
panel keystroke or an auto­matic copy (Note 1)

Memory-Display

Front panel keystroke or an
automatic operation (Note 2)

Memory-Relays

Bus command or any valid

trigger
Memory-Controller
Memory-Memory
Relays-Display

Bus command

Bus command

Front panel keystroke or an

automatic operation (Note 3)
Relays - Memory
Relays-Controller
Controller-Memory
Controller-Relays

Notes:

1. Generation of the automatic copy is selected by a front panel key.
(AUTOMATIC LED is lit.)

2. The automatic operation is generated if the displayed setup has been
changed by a bus command and has not been modified from the front
panel. (MEMORY LED is lit.)

3. The automatic operation is generated if the displayed setup has been
changed by a trigger or bus command and has not been modified
from the front panel. (RELAYS LED is lit.)

4. Controller modifications to setups are reflected on the crosspoint dis­play if the affected setup is currently being displayed.

5. Front panel keystrokes can be generated by bus commands.

Bus command
Bus command
Bus command
Bus command

4.3 Power-up procedure

The steps in the following paragraphs take you through the
basic procedures for selecting the line voltage, connecting
the instrument to line power, and turning on the instrument.

4.3.1 Line voltage selection

The Model 707A operates from a line voltage in the range of
100 to 240V, at a frequency of 50 or 60Hz. Line voltage and
frequency are automatically sensed, therefore there are no
switches to set. Check to see that the line power in your area
is compatible.

4.3.2 Line power connections

Using the supplied power cord, connect the instrument to an
appropriate 50 or
the cord connects to the ac receptacle on the rear panel of the
instrument. The other end of the cord should be connected to
a grounded ac outlet.

60Hz

ac power source. The female end of

WARNING

The Model 707A must be connected to a
grounded outlet to maintain continued
protection against possible shock haz­ards. Failure to use a grounded outlet
may result in personal injury or death
due to electric shock.

4.3.3 Power switch

T o turn on the power , simply push in the front panel PO WER
switch. Power is on when the switch is at the inner (1) posi­tion. To turn power off, press POWER a second time.

4.3.4 Power-up self-test and messages

During the power-up cycle, the instrument performs the fol­lowing tests. The first five operations are transparent to the
user unless an error occurs.

1. A checksum test is performed on ROM and a read/write
test on RAM. If an error is found, the self-test continues
and the unit displays either ROM FAIL or RAM FAlL
when the test has completed. You can override either
type of error with a front panel keypress. The Model
707A will attempt normal operation.

NOTE

If a problem develops while the
instrument is still under warranty (1ess
than one year from shipment date), return
it to Keithley Instruments, Inc. for repair.
For units out of warranty refer to Section
6, Maintenance.

2. The Model 707A reads identity information from each
card and performs a checksum test on the data. If the
checksum test fails on one or more matrix cards, the
instrument displays CARD ID ERROR and lights all
crosspoint LEDs of that card. Any keypress will allow
the unit to continue. An empty slot will not produce an
error.

3. A checksum test is performed on all setups in memory.
If the instrument detects a checksum error in one or
more stored setups, it displays the message SETUP
ERROR and clears the crosspoints bits of the setup(s) in
error. The message remains displayed until a key is
pressed.

NOTE

The SETUP ERROR message may be an
indication of a low battery. Cycle power
off and on. If the message reappears, see
paragraph 7.7 for battery replacement
procedure.

4-2

Operation

4. The present card configuration (i.e., which cards are in­stalled in which slots) is compared with the unit's previ­ous configuration. If there is a change, the 100 setups in
memory are reformatted. (The front panel display is
blanked out during this time.) Crosspoint closures are
not affected, just the way a setup is stored for the differ ­ent cards.

5. If the unit was previously programmed as a stand-alone
or slave unit, it powers up as a stand-alone. If the unit
was programmed as a master the last time it was on, it
checks for additional units in a serial looped configura­tion and tries to make them slave units. (Refer to para­graph 4.3.6 for information concerning turning on a
master/slave configuration.)

The message M/S ERROR is displayed if there is not a
closed loop (the Model 707A can be looped back to it­self). Any keypress or IEEE-488 bus operation will al­low the unit to continue as a stand-alone unit.

6. The instrument performs the display test, where it lights
all segments of the alphanumeric display, all crosspoint
LEDs, and all other LED indicators. Then it briefly dis­plays the software revision level and the programmed
primary IEEE-488 address as in this example:

A01 IEEE 18

Knowing the software revision level is useful when dis­cussing problems with Keithley Instruments. In this ex­ample, the factory default primary IEEE-488 address is
displayed. The actual address depends on the pro­grammed value.

4.3.5 Power-up configuration

After the power-up tests and display messages are com­pleted, the Model 707A assumes specific operating states:

• All relays are opened.

• The RELAYS indicator is lit (crosspoint display shows
current relay setup).

• The RELA Y STEP field is set to 000 and the MEMOR Y
STEP field is set to 001.

• Trigger disabled.

Table 4-2 summarizes the power-up configuration for the
unit. The entire power-up process takes approximately five
seconds to complete.

Table 4-2

Power-up, reset, and factory defaults

Parameter

Relays
Stored setups
RELAY STEP
MEMORY STEP
Digital output
External trigger
Matrix ready
Master/slave

IEEE-488 address
Programmed settling time
Make/break rows
Break/make rows
Trigger enable
Trigger source

Power-up/reset
default Factory default

All opened
Unchanged
000
001
000
Falling edge
Active low
Unchanged
(if successful)
Unchanged
0msec
Unchanged
Unchanged
Disabled
External

All opened
All cleared
000
001
000
Falling edge
Active low
Unchanged

18
0msec
None selected
None selected
Disabled
External

4-3

Operation

4.3.6 Master/slave power-up

The power-up sequence for Model 707A mainframes can be
summarized as follows:

Each unit connected in the master/slave loop displays M/S
LOOP DOWN until all units are powered up.

• Units previously programmed as stand-alones or slaves
power up as stand-alones.

• A unit previously programmed as a master powers up as
a master and tries to initiate a loop connection. If it is
successful, other units in the loop become slaves. If it is
not successful, the message M/S ERROR is displayed
and the unit reverts to stand-alone operation.

T o connect and power up a master/sla ve configuration for the
first time, follow these steps:

1. Connect up to five mainframes in a daisy chain (Master/
Slave Out of one unit to Master/Slav e In of ne xt unit) as
previously shown in Figure 3-14 for two units.

2. Power up each unit. Since there is no master in the loop
as yet, all units will power up as stand-alones. The units
will display the message M/S LOOP DOWN until all
are turned on.

3. From the front panel of the desired master unit, press the
MENU key until the alphanumeric display shows:

STANDALONE

Press one of the SCROLL keys to change the display to
MASTER, then press ENTER. This action initiates a loop
connection, making this unit the master and the other units
slaves, and exits menu mode.

During subsequent power-ups of master/slave configura­tions, all connected mainframes wait for all units to get

power before initializing. Thus, it is not necessary to turn on
the master unit last.

CAUTION

When it is necessary to cycle power on a
slave unit, turn off all units in the
master/slave configuration. This pro­cedure prevents the open communi­cation and control loop from putting the
slave unit in an undesirable state.

4.4 Displays and messages

4.4.1 Alphanumeric display

The alphanumeric display is a 14-character display that can
show error messages, informational messages (e.g., menu
item parameters), last setup sent to relays, last setup recalled
to crosspoint display, trigger source, programmed settling
time, and alphanumeric key presses. See Figure 4-2.

The 3-digit RELAY STEP field of the alphanumeric display
shows the location of the last setup sent from memory to the
relays. A trigger causes the ne xt setup (RELAY STEP +1) to
be sent to the relays.

The 3-digit MEMORY STEP field of the alphanumeric dis­play shows the location of the last setup recalled from mem­ory to the crosspoint display.

The 6-digit data entry scratchpad field reflects alphanumeric
key presses by the user, such as row and column addresses
and setup locations.

KEITHLEY

RELAY STEP MEMORY STEP

Figure 4-2

Alphanumeric display

4-4

707A SWITCHING MATRIX

TALK

LISTEN

REMOTE

Operation

4.4.2 Display messages

During Model 707A operation and programming, you will
encounter a number of front panel messages on the alphanu­meric display. Typical messages will be either of error or
informational variety, as discussed in the following para­graphs.

Error Messages

Error messages are divided into two categories: those which
stay on the display until a keypress or some other operation
changes the display, and those which appear for tw o seconds
and then the display returns to its previous state.

Table 4-3

Error messages

Message Description Corrective Action

CARD ID ERROR*

IDDC
IDDCO

INVALID INPUT

LIGHT PEN????

M/S ERROR*

M/S LOOP DOWN

NOT IN REMOTE

RAM FAIL*
ROM FAIL*
SETUP ERROR*

TRIG OVERRUN

* Message remains displayed until next operation.

Checksum test failed on one or more matrix cards.

Invalid device-dependent command.
Invalid device-dependent command option.

Invalid crosspoint address, setup location, make/
break or break/make row, or parameter out of
range.
Light pen button pressed when pen was not pointed
at crosspoint LED or make/ break or break/make
LED.
Error in master/slave communication loop (over­run, parity, framing, count imbalance, or time-out).
One or more units connected in master/slave loop
are not powered up.
“X” character received over IEEE-488 bus but
Model 707A is not in remote.
Self-test detected error in RAM.
Self-test detected checksum error in ROM.
Self-test detected checksum error in stored setup.
Battery may be low.
An additional trigger was received before the
Model 707A asserts the READY signal.

Table 4-3 lists Model 707A error messages. Many of these
messages are also covered in pertinent paragraphs of the
manual. Where applicable, the necessary correctiv e action is
also given in the table.

Informational messages

Informational messages are included as a programming aid.
No corrective action is necessary, but you still may be
required to enter a parameter at the prompt. Table 4-4 lists
Model 707A informational messages. Again, most of these
are covered in other parts of the manual.

Remove card identified by all crosspoint LEDs
lit.
Send only valid commands (see Section 5).
Send only valid command options (see
Section 5).
Enter valid data.

Press button with pen perpendicular to LED.

Check for a closed loop of MASTER/SLAVE
OUT to MASTER/SLAVE IN.

Turn on all units or reconfigure master/slave loop.
Put Model 707A in remote.

See troubleshooting in Section 7.
See troubleshooting in Section 7.
Affected setup is cleared, then Model 707A pro­ceeds normally.
Check the READY bit in the serial poll byte.

4-5

Operation

Table 4-4

Information messages

Message Key(s) Description

IN 255 OUT 000 MENU Digital input status and digital output parameter

(decimal values).
EXT TRIG FALL MENU Falling edge external trigger pulse.
EXT TRIG RISE MENU Rising edge external trigger pulse.
MATRIX RDY LO MENU Matrix Ready pulse active low.
MATRIX RDY HI MENU Matrix Ready pulse active high.
STANDALONE MENU Stand-alone operation of Model 707A.
MASTER MENU Master unit in master/slave configuration.
IEEE-488 18 MENU IEEE-488 bus address of 18.
HWSETL 015 mS MENU Longest relay settling time of present card con-

figuration (Model 7073 is shown).
1 7071 MENU Card configuration by slot and model number

(Model 7071 in slot 1 is shown).
SELF TEST MENU Item to select self-test execution.
FACTORY INIT MENU Item to select factory defaults (setups cleared).
SETL 00000 mS SETTLING TIME Programmed settling time (added to relay set-

tling time).
TRIG ON EXT SOURCE External trigger pulse triggering.
TRIG ON KEY SOURCE Front panel key triggering.
TRIG ON TALK SOURCE IEEE talk command triggering.
TRIG ON GET SOURCE IEEE GET command triggering.
TRIG ON X SOURCE IEEE X command triggering.
NOT SETTLED — Additional trigger received before programmed

settling time expired (trigger is processed).

4.4.3 IEEE-488 status indicators

The TALK, LISTEN, and REMOTE LEDs (shown in Figure
4-2) indicate these modes when the Model 707A is being
programmed over the IEEE-488 bus. The TALK and LIS­TEN indicators show when the unit has been addressed to
talk or listen. These talk and listen commands are derived
from the unit’s primary address. REMOTE turns on to show
when the unit is placed in remote by addressing it to listen
with the REN line true. (All front panel controls except
LOCAL and POWER are inoperativ e when REMOTE is on.)
Local operation is restored by pressing LOCAL unless the
IEEE-488 LLO (Local Lockout) command is in effect. See
Section 5 for details of IEEE-488 bus operation.

4-6

4.4.4 Crosspoint display LEDs

As shown in Figure 4-3, the crosspoint display has six blocks
of LEDs (one per card slot). Each block has 8 rows (A-H)
by12 columns (1-12, 13-24, etc.) of LEDs. The display LEDs
can show the current open/closed relay states, the on/off
states of a setup from in memory, or the on/off states of a
setup currently being edited. The on/off states of crosspoint
LEDs can be changed by front panel keys, commands over
the bus, or an optional light pen. Modified displays can be
stored in memory or sent to the relays.

Operation

Figure 4-3

Crosspoint display

4-7

Operation

4.4.5 Make/break and break/make LEDs

The MAKE/BREAK and BREAK/MAKE displays each
have two blocks of LEDs labeled A-H (one for columns
1-36, the other for columns 37-72). Refer to Figure 4-3. Each
block shows which rows have been selected for make/break
or break/make operation. When switching current sources,
use make/break operation to keep current flowing and elimi­nate switching transients. When switching voltage sources,
use break/make operation to avoid momentary shorting of
two paths together.

The LEDs can be turned on or off by pressing a row letter ke y
and the MAKE/BREAK or BREAK/MAKE key, or with an
optional light pen. Note that selecting a row for break/make
de-selects it for make/break and vice versa.

4.4.6 Light pen

The light pen is an optional input device for toggling the on/
off states of crosspoint display LEDs, MAKE/BREAK row
LEDs, and BREAK/MAKE row LEDs. One light pen is used
to control the LEDs of all units in a master/slave system.

As seen in Figure 4-4, the light pen plugs into the front panel
of stand-alone or master units. Remove the light pen by
pressing the button on the connector plug while pulling out
the plug. Mount the light pen holder on the left handle of the
Model 707A by tightening the allen-head screw shown in
Figure 4-4.

To toggle the state of a crosspoint LED or MAKE/BREAK,
BREAK/MAKE LED with the light pen, follow these steps:

1. Hold the light pen as you would an ordinary pen.

2. With the light pen perpendicular to the front panel
overlay at the desired LED, press the button on the pen's
barrel.

3. Proper usage will toggle the state of the LED. If the but­ton is pressed while not on an LED, the message LIGHT
PEN???? is displayed briefly, then the Model 707A
reverts to its previous display.

4-8

Operation

Figure 4-4

Light pen

4-9

Operation

4.5 Selecting crosspoint display

In the CROSSPOINT DISPLAY key group on the front
panel are two keys that are used to bring setups to the cross­point display. See Figure 4-5. Three LEDs in the group indi­cate the source of setup data. Only one of these LEDs is lit at
a time:

• MEMORY LED — When lit, the crosspoint display
shows a setup stored in memory.

• RELAYS LED — When lit, the crosspoint display
shows the current relay setup.

• CROSSPOINT DISPLAY MODIFIED LED — When
lit, the crosspoint display shows a modified setup that
was previously from memory or from the relays.

CROSSPOINT DISPLAY

COPY

MEMORY

RE LAYS

CROSSPOINT
DISPLAY
MODIFIED

DISPLAY MEMORY

COPY
DISPLAY MEMORY

AUTOMATIC

When the MEMORY indicator is lit, a setup can also be dis­played by entering a valid location and pressing ENTER, or
by pressing a SCROLL key to display the setup at MEM­ORY STEP ±1. If you press and hold a SCROLL key, the
MEMORY STEP field is updated continuously. As location
000 is invalid for MEMORY STEP, the SCROLL keys skip
this location when incrementing or decrementing.

If the displayed setup is modified by IEEE-488 commands,
the crosspoint display changes if the MEMORY indicator is
lit. In other words, if you are editing a setup, changes to its
source do not appear.

Pressing the RELA YS ke y displays the current relay setup on
the crosspoint display and lights the RELAYS indicator. If a
valid location (0400) is entered first, that setup is sent to the
relays and displayed on the crosspoints and in the RELAY
STEP field. When location 000 is selected in this manner , the
relay states do not change.

When the RELAYS indicator is lit, a setup can also be sent
to the relays and displayed by entering a valid location and
pressing ENTER, or by pressing a SCROLL key to send and
display the setup at RELAY STEP ±1. If you press and hold
a SCROLL key, the RELAY STEP field is updated continu­ously. As the SCROLL keys increment and decrement the
RELAY STEP field through location 000, there is no effect
on the relays. That is, when the RELAY STEP is decre­mented from 001 to 000, or when incremented from 100 to
000, the relays do not change state.

Figure 4-5

Crosspoint display keys

Pressing the MEMORY key displays a stored relay setup
(location shown in MEMORY STEP field) on the crosspoint
display and lights the MEMORY indicator . If a v alid location
(1400) is entered first from the data entry keypad, that setup
is displayed on the crosspoints and in the MEMORY STEP
field. (The INVALID INPUT message is displayed briefly
for locations out of range.) The CANCEL key can be used to
remove incorrect entries from the alphanumeric display.

If the relays change due to a trigger or IEEE-488 commands,
the crosspoint display changes only if the RELA YS indicator
is lit.

4.6 Modifying crosspoint display

After choosing the source of the setup, a crosspoint display
can be modified by turning on/off crosspoint LEDs with
front panel keys or the light pen. As discussed in the next
paragraph, if the AUTOMATIC (COPY DISPLAY →
RELAYS) indicator is lit, these actions open/close relays
immediately.

The alphabetic data entry keys (A-H) are for entering the row
part of a crosspoint address. The numeric keys (0-9) are for
entering column numbers. Use the CANCEL key to remove
incorrect entries from the alphanumeric display. Refer to
Figure 4-6.

4-10

Operation

G

E

C

A

H

F

D

B

Figure 4-6

Data entry keys

The maximum valid column number with a single unit is 72.
If several mainframes are connected and programmed for
master/slave operation, the maximum column can be up to
360 (with five units).

When a valid crosspoint address (row and column) is in the
alphanumeric display, pressing the OPEN key turns off the
crosspoint display LED. (The message INVALID INPUT is
displayed for addresses out of range.) If the AUTOMATIC
(COPY DISPLAY → RELAYS) indicator is lit, the corre­sponding relay opens immediately. The CLOSE key per­forms the same action as the OPEN key except that it turns
on crosspoint display LEDs and relays.

Pressing the CLEAR key turns off all crosspoint display
LEDs. If the AUTOMA TIC (COPY DISPLAY → RELAYS)
indicator is lit, all relays are opened immediately.

The CROSSPOINT DISPLAY MODIFIED indicator lights
and the MEMORY or RELAYS indicator go out when
changes are made to the crosspoint display, making it differ­ent from the configuration of its source. It also lights when
opening an already open crosspoint and closing an already
closed crosspoint. The SCROLL k eys are not active when the
CROSSPOINT DISPLAY MODIFIED indicator is lit.

The optional light pen can also be used to turn on and off
crosspoint LEDs. Just hold it perpendicular to the front panel
overlay at the desired LED and press the button on its barrel.
This action toggles the state of the LED.

The maximum number of simultaneously closed cross­points depends on the specified drive current per crosspoint
of each card. The total relay drive current required per main­frame cannot exceed 48.5A, since the 6V/50A power supply
also provides 1.5A for the front panel display.

7

4

1

0

8

5

2

CANCEL ENTER

9

6

3

4.7 Copying crosspoint display

The setup data displayed on the crosspoint LEDs can be
stored in non-volatile memory of the Model 707A or can be
sent directly to the relays by pressing either the COPY DIS­PLAY → MEMORY or the COPY DISPLAY → RELAYS
key, seen previously in Figure 4-5.

With the COPY DISPLAY → MEMORY key, the displayed
crosspoint configuration is stored at the setup location shown
in MEMORY STEP field. It o verwrites the present setup data
at that location. If a valid location is keyed in first, pressing
this key stores the crosspoint configuration at that setup and
sets the MEMORY STEP field to that location. If the
CROSSPOINT DISPLAY MODIFIED indicator is lit, it
goes out and the MEMORY LED lights. The INVALID
INPUT message is displayed briefly if you try to copy to a
setup location below one or above 100.

In master/slave configurations, each unit stores its own por­tion of each stored setup.

When the COPY DISPLAY → RELAYS key is pressed, the
displayed crosspoint configuration is sent to the relays:

• If the MEMORY indicator is lit (i.e., the crosspoint dis­play shows an unmodified setup from memory), the
RELAY STEP field is set to the MEMOR Y STEP field.
In effect, this copies a setup from memory to the relays.

• If the RELAYS indicator is lit, the RELAY STEP field
is not affected, as it reflects the last stored setup sent to
the relays.

• If CROSSPOINT DISPLAY MODIFIED is lit, it goes
out and the RELAYS LED lights.

4-11

Operation

Copying the crosspoint display to the relays can be per­formed automatically with the toggle-action AUTOMATIC
(COPY DISPLAY → RELAYS) key. When the AUTO­MATIC indicator is lit, any change to the crosspoint display
is also sent to the relays at the same time. This action is
apparent when scrolling through unmodified stored setups,
as the MEMORY STEP and RELAY STEP fields will
sequence together. Changes to the crosspoint display while
the AUTOMATIC LED and RELAY LEDs are lit cause the
CROSSPOINT DISPLAY MODIFIED LED to blink and the
RELAYS LED to remain lit.

4.8 Inserting and deleting stored setups

The two keys in the MEMORY group (see Figure 4-7) oper­ate on setups stored in Model 707A memory. These keys are
active only when the MEMORY LED is lit.

MEMORY

INSERT

DELE TE

If a valid location is keyed in first, the MEMORY STEP field
is set there and then the insert operation takes place.

Pressing the DELETE key removes the stored setup at the
location shown in the MEMORY STEP field. While the
delete is taking place, the alphanumeric display is blank. All
setups higher than the selected setup are moved down one
location. (Setup 100 is cleared.) After the delete operation,
the crosspoint LEDs display the new setup “nnn”, which pre­viously was setup “nnn+1”.

If a valid location is keyed in first, the MEMORY STEP field
is set there and then the deletion takes place.

In master/slave configurations, the insert blank setup and
delete stored setup operations perform similarly, except on
all units of the system.

4.9 Menu operations

The Model 707A has several operations that are performed
by front panel menu items. Select the first item by pressing
the MENU key, subsequent presses of MENU display the
remaining items (see Table 4-5). To view all current menu
selections just press and hold the MENU key.

Figure 4-7

Memory keys

Use the INSERT key to place a blank setup at the memory
location shown in the MEMORY STEP field. While the
insert is taking place, the alphanumeric display is blank. All
setups from the selected setup through 99 are moved up one
location. (Setup 100 is deleted by overwriting it with setup

99.) After the insert operation, the crosspoint LEDs display
a blank setup.

Status items are displayed with no user action. Numeric
items are modified by keying in the desired value with the
data entry keys and pressing ENTER. Multiple choice items
are selected by scrolling through the choices until the desired
one is displayed, then pressing ENTER. Immediate action
items are invoked by pressing ENTER.

If no modifications are made with the SCROLL or data entry
keys, pressing CANCEL exits from the menu without chang­ing any values; otherwise CANCEL restores the current
value of the parameter . Pressing ENTER exits from the menu
(with changes), except when programming the digital output
status.

4-12

Table 4-5

Menu operations

Message Item Description Type

Operation

IN iii OUT 000

EXT TRIG FALL
EXT TRIG RISE

MATRIX RDY LO
MATRIX RDY HI

STANDALONE
MASTER

IEEE-488 nn

HWSETL nnn mS

n cccc

SELF TEST

FACTORY INIT

View digital input, program digital output.

Select which edge of external trigger pulse triggers Model 707A (falling
or rising).

Select matrix ready output level (active LO or HI).

Select stand-alone or master/slave operation.

Program IEEE-488 bus address.

View longest relay (hardware) settling time of cards in system.

View slot number (n) and card label (cccc).

Execute self test.

Return to factory defaults. (All stored setups are cleared.)

status/numeric

multiple choice

multiple choice

multiple choice

numeric

status

status

immediate action

immediate action

4-13

Operation

4.9.1 Digital I/O

The TTL-compatible DIGITAL I/O port has eight data lines
for inputs, eight data lines for outputs, and two control lines
for handshaking. The pinout for the rear panel DB-25 con­nector is shown in Figure 4-8. Status of the input lines is
viewed and states of the output lines are programmed
through the first menu item. With no input connections and
power-up default conditions for the output, the alphanumeric
display will read the following decimal values:

IN 255 OUT 000

13

12

11

10

9

8

7

6

5

4

3

2

1

NO CONNECTION

GND

IN7

IN6

IN5

IN4

IN3

IN2

IN1

IN0

GND

INLATCH

GND

GND

OUT7

OUT6

OUT5

OUT4

OUT3

OUT2

OUT1

OUT0

GND

OUTPULSE

GND

25

24

23

22

21

20

19

18

17

16

15

14

16

The digital inputs are logic high with no connections. Use
the control line INLATCH (low true) to latch in the digital
inputs when changing an input state.

To program the digital output states, select the desired deci­mal value with the data entry keys and press ENTER. You
can now key in another value and press ENTER, or press
CANCEL to exit menu mode, or press MENU to continue to
the next item. Each time the digital outputs are programmed,
even if the states are not changed, the control line OUT­PULSE is brought low.

With master/slave configurations, only the DIGITAL I/O
port of the master unit is available for viewing and
programming.

4.9.2 External trigger

If triggers are enabled, and external trigger is selected as a
source, a TTL-compatible pulse of at least 600nsec duration
at the rear panel EXTERNAL TRIGGER INPUT jack trig­gers the Model 707A. The input BNC jack is shown in Figure
4-9.

EXTERNAL
TRIGGER

INPUT

MATRIX
READY

OUTPUT

Figure 4-9

Rear panel BNC jacks

The unit can be programmed with a menu item for which
edge (falling or rising) of the external trigger pulse causes a
transfer of stored setup data to the relays. Sample trigger
pulses are shown in Figure 4-10. To select which pulse edge
triggers, use the MENU key to choose the menu item for
external trigger. The power-up default display will read:

Figure 4-8

Digital I/O port

4-14

EXT TRIG FALL

Relay Settling Time +

Program m ed S ettling T im e

TTL High

( 3.4V Typical )

TTL Low

( 0.25V Typical )

A. M atrix ready high true

Program m ed S ettling T im e

B. M atrix ready low true

Relay Settling Time +

(3.4V Typical )

TTL High

TTL Low

( 0.25V Typical )

Operation

TTL High

(3.4V Typical )

TTL Low

( 0.25V Typical )

TTL High

(3.4V Typical )

TTL Low

( 0.25V Typical )

Falling

Edge

600nsec

Minimum

A. Falling edge of puls e

Rising

Edge

600nsec

Minimum

B. Ris ing edge of pulse

4.9.3 Matrix ready

The Model 707A provides a TTL-compatible signal at its
rear panel MATRIX READY OUTPUT jack. The output
BNC jack was shown in Figure 4-9. The MATRIX READY
signal goes false when relays are switched and goes true at
the end of the programmed settling time. (As described in
paragraph 4.11, this is also after the relay settling time.)

Through a menu item, the unit can be programmed for a
high- or low-true MATRIX READY signal, as seen in Figure
4-11. T o select the acti ve state of the signal, press the MENU
key until the MATRIX RDY item is displayed. The power -up
default display will read:

MATRIX RDY LO

Figure 4-10

Sample external trigger pulses

To choose the alternate external trigger state, use the
SCROLL or keys, then press ENTER. This action

also exits from the menu mode. (Pressing CANCEL instead
of ENTER returns external trigger to its previous state and
the Model 707A remains in menu mode.)

In master/slave configurations, only the EXTERN AL TRIG­GER INPUT port of the master unit is active.

See paragraph 4.11 for more information on triggering the
Model 707A.

Figure 4-11

Sample matrix ready pulses

T o choose the other acti v e state, use the SCROLL or
keys, then press ENTER. This action also exits from the
menu mode. (Pressing CANCEL instead of ENTER returns
matrix ready to its previous state and the Model 707A
remains in menu mode.)

In master/slave configurations, the MATRIX READY sig­nals of all units function, but only that of the master is to be
considered accurate.

4-15

Operation

4.9.4 Stand-alone and master/slave

One method to expand system size is to connect up to five
mainframes in a master/slave configuration, where all units
are daisy-chained for serial communication and control. Sys­tem operations are performed through the master unit, either
over the IEEE-488 bus or the master's front panel (including
the light pen). A master/sla ve system appears as a single unit
(and IEEE-488 address) with a maximum size of 8 rows by
360 columns. Selection of stand-alone or master/slave oper­ation is done with a menu item.

As previously described in paragraph 3.5, the MASTER/
SLAVE OUT and MASTER/SLAVE IN rear panel connec­tors are used to connect DIN cables in a closed loop. The
connector pinouts are defined in Figure 4-12.

7

8

5

4

2

6

3

1

This action is performed by pressing the MENU key of the
desired master mainframe until the display reads STAND
ALONE. Next, scroll up or down to the MASTER message.
Then, press the ENTER key to initiate the master/slave loop.
If the loop is complete (MASTER/SLAVE OUT to MAS­TER/SLAVE IN in a daisy chain among all units), the master
unit will exit menu mode and the other units will display
SLAVE 1, SLAVE 2, etc. (The slave number is determined
by the unit's position in the loop.) If the loop of DIN cables
is not closed, the master will display the message M/S
ERROR and all units will remain as stand-alones.

When the units are powered up one at a time, they will
display the message M/S LOOP DOWN until all units are
powered.

CAUTION

When it is necessary to cycle power on a
slave unit, turn off all units in the
master/slave configuration. This pro­cedure prevents the open communi­cation and control loop from putting the
slave unit in an undesirable state.

During master/slave operation, most front and rear panel
controls of the slave units are inactive. Table 4-6 shows
which controls and indicators remain active for slave units.

Pin Master/Slave IN Master/Slave Out
1 M/S TRIGGER (low true) M/S TRIGGER (low true)

2 ALLREADY ALLREADY
3 LPRESET (low true) LPRESET (low true)
4 LPSENSE (low true) LPSENSE (low true)
5 RxDATA TxDATA
6-8 Chassis Ground Cha ssis Ground

Figure 4-12

Master/slave connectors

After interconnecting and powering up all units, one unit is
selected to be a master.

The master unit communicates with the slaves only when
necessary; it does not continuously monitor the status of the
closed-loop configuration. Hence, a disconnected master/
slave loop cable is not detected, and the message M/S
ERROR is not displayed, until the master attempts to send or
receive data around the loop. The steps tak en by a master unit
to recover from an M/S ERROR are outlined below:

1. The master stops processing IEEE-488 bus commands,
returns to stand-alone operation, and disables.

2. The slave units remain the same as before the error
occurred.

3. To re-initialize the loop, ensure that master/slave cables
are secure, and select master/slave operations from the
mainframe that previously was master.

4-16

Operation

Table 4-1

Status of slave unit controls

Control, indicator, or connector Status

POWER active
CROSSPOINT DISPLAY Group:

MEMORY key and LED only LED active
RELAYS key and LED only LED active
CROSSPOINT DISPLAY

active
MODIFIED LED
COPY DISPLAY — MEMORY inactive
COPY DISPLAY — RELAYS inactive
AUTOMATIC key and LED only LED active

SCROLL and SCROLL inactive
MEMORY Group:

INSERT inactive
DELETE inactive

MENU key and LED inactive
SWITCHING Group:

SETTLING TIME inactive
MAKE/BREAK inactive
BREAK/MAKE inactive

LOCAL inactive
TRIGGER Group:

ENABLE key and LED only LED active
SOURCE inactive
MANUAL inactive

Data Entry (A-H, 0-9) inactive
CANCEL, ENTER inactive
RESET inactive
CLEAR, OPEN, CLOSE inactive
Alphanumeric Display active (Note 1)
TALK, LISTEN, REMOTE LEDs inactive
Crosspoint Display LEDs active
MAKE/BREAK and BREAK/MAKE

active

Row LEDs
LIGHT PEN inactive

Rear Panel Connectors:

MASTER/SLAVE IN active
MASTER/SLAVE OUT active
EXTERNAL TRIGGER INPUT inactive
MATRIX READY OUTPUT active (Note 2)
REALY TEST not used
DIGITAL I/O inactive (Note 3)
IEEE-488 INTERFACE not used

Notes:

1. Messages only.

2. Timing accuracy not guaranteed.

3. Outputs set to all low.

4.9.5 IEEE-488 bus address

The Model 707A communicates over the IEEE-488 bus
through the rear panel connection shown in Figure 4-13.
When connected to a bus controller, instrument operating
modes can be programmed. Note that IEEE-488 common is
always grounded. IEEE-488 interface function codes are
marked adjacent to the connector.

SH1

AH1

T6
TE0
L4
LE0
SR1
RL1
PP0
DC1
DT1
E1
C0

Figure 4-13

IEEE-488 bus connector

A menu item is used to set the primary address of the Model
707A for bus operation. The primary address of the Model
707A is factory set to 18, but it may be set to any value
between 0 and 30 as long as address conflicts with other
instruments or the bus controller are avoided.

To check the present primary address or to change to a new
one, perform the following procedure:

1. Press the MENU key until the current primary address
is displayed. For example, if the instrument is set to pri­mary address 18, the following message is displayed:

IEEE-488 18

2. Press CANCEL to retain the present address and exit
menu mode.

3. To change the primary address, use the data entry keys
to key in a new value, then press ENTER. This action
will also exit menu mode. The new address will be
stored in memory so that the instrument powers up to
that address.

IEEE-488 INTERFACE

4-17

Operation

NOTE

Each device on the bus must hav e a unique
primary address. Failure to observe this
precaution will probably result in erratic
bus operation.

Section 5 contains detailed information on operating the
Model 707A over the IEEE-488.

4.9.6 Relay (hardware) settling times

The card specification “relay settling time” is the time
needed for the relays to actuate or release (including contact
bounce time) and pass a clean signal. Since this specification
is card dependent, the Model 707A must identify on power­up which cards are installed to determine the longest relay
settling time in the system (stand-alone or master/slave).
This value is not user-modified, but the total settling time for
a switching operation can be lengthened by using the pro­grammed settling time, as explained in paragraph 4.10.

To view the relay (hardware) settling time of the system,
press the MENU key until the display reads:

HWSETL 015 mS

In this example, there is a Model 7072 or 7073 matrix card
present in the system. Press CANCEL to exit the menu
mode.

See paragraph 4.11 for a discussion of settling times and
triggers.

4.9.7 Card labels

Each matrix card can be identified by the Model 707A. You
can view the card labels of the present configuration by using
a menu item. Press the MENU key until the alphanumeric
display reads:

4.9.8 Self-test

The self-test program is intended to check ROM, RAM, and
the front panel LED indicators. This test is also part of the
power-up sequence. If you want to run the test without
cycling power, use the following procedure to select and run
it:

1. Press the menu key until the display reads SELF TEST.

2. Press the ENTER key to initiate the test. The unit's R OM
and RAM are checked. Next, all the front panel LEDs
are lit for your inspection. If no errors are detected,
menu mode is exited.

If there is an error in ROM or RAM, a ROM FAIL or RAM
F AIL message is displayed until a key press or b us operation.
See Section 7 for troubleshooting procedures.

For master/slave configurations, all units are tested simulta­neously, so you might have to run the test more than once to
inspect all LED indicators.

4.9.9 Factory defaults

A menu item can be used to return the Model 707A to the
factory default conditions previously listed in Table 4-2. To
initiate this action, follow these steps:

1. Press the MENU key until the display shows FACTOR Y
INIT .

2. Press the ENTER key. The display will read ENTER IF
SURE. (This additional keypress is to prevent uninten­tional initialization.) At this step you can press CAN­CEL to exit menu mode, or you can continue with the
next step.

3. Press the ENTER key again. The Model 707A will re­turn to factory settings and exit menu mode.

In master/slave configurations, all units return to factory
defaults when this menu item is selected from the master
unit.

1 7072

In this case, a Model 7072 is in slot #1. Use the SCROLL to
view the card label of the next slot. If no card is present, the
display will be:

2 NONE

Continue pressing the SCROLL or keys for the
remaining slots or press CANCEL to exit the menu mode.

In master/slave configurations, all units display card labels
simultaneously.

4-18

Operation

4.10 Selecting switching parameters

The Model 707A has three switching parameters that are
user-modified: the programmed settling time, make-before­break rows, and break-before-make rows. These values of
these parameters are in effect for all relay switching until
they are changed. Figure 4-14 shows the front panel keys of
the switching group.

SWITCHING

SETTLING TIME

MAKE/BREAK

BREAK/MAKE

Figure 4-14

Switching keys

4.10.2 Make/break and break/make rows

Make-before-break switching of relays is defined as con­necting a new circuit before disconnecting the present cir­cuit. It is used to eliminate transients caused by switching
between current sources. Break-before-make switching
means to disconnect the present circuit before connecting a
new circuit. It is used to avoid momentary shorting of two
voltage sources. Both of these switching operators are sup­ported by the Model 707A.

Rows of crosspoint relays are user-selectable for make/break
(make-before-break), break/make (break-before-make), or
“don't care” operation. The selections will be in effect for all
switching until new choices are made. When make/break or
break/make operation is chosen, the Model 707A automati­cally switches the crosspoint relays through intermediate set­ups to perform the following steps:

1. Crosspoints in break/make rows are opened.

2. Crosspoints in make/break rows are closed.

3. Crosspoints in make/break rows are opened.

4. Crosspoints in break/make rows are closed; crosspoints
in “don't care” rows are opened or closed accordingly.

4.10.1 Programmed settling time

The programmed settling time is a variable switching delay
that can be used to lengthen the fixed delay of the relay
(hardware) settling time. You can select, in 1msec incre­ments, up to 65 seconds of an additional switching delay.

If an additional trigger is received during this time, it is pro­cessed and the message NOT SETTLED is displayed. At the
end of the programmed settling time. the Model 707A sets
the MATRIX READY output true.

To view or change the programed settling time, press the
SETTLING TIME key in the SWITCHING key group. The
value of the programmed settling time value is displayed as:

SETL 00000 mS

To exit the display without changing the value, just press
CANCEL. To change the value, enter between 0-65000 with
the data entry keys and press ENTER. This action also
returns the display to the RELAY STEP and MEMORY
STEP.

The programmed settling time is in effect for all crosspoint
relay open/close operations until it is reprogrammed. Its
effect on trigger response times is described in paragraph

4.11.

These steps are transparent to the user except for the in­creased settling time. If either make/break or break/make
rows are not selected, the appropriate steps in the previous
list are deleted and the total settling time decreases. As make/
break and break/make operations affect settling times and
trigger response, these operations are further discussed in
paragraph 4.11.

The front panel MAKE/BREAK and BREAK/MAKE keys
are used in conjunction with the data entry keys to select
rows for operation as make/break or break/make. When a
row designation (A-H) is selected and displayed by itself, the
MAKE/BREAK and BREAK/MAKE keys toggle the state
of the MAKE/BREAK or BREAK/MAKE LED for that row
and immediately reprograms the Model 707A for the new
operation. The INVALID INPUT message is displayed
briefly if you press the MAKE/BREAK or BREAK/MAKE
key without first selecting a row or if a row/column address
is displayed instead of just a row.

Note that selecting a row for make/break de-selects it for
break/make and vice versa. The various front panel opera­tions are listed in Table 4-7.

4-19

Operation

Table 4-7

Make/break and break/make front panel operation

Present State Action Next State

Don't Care

Make/Break

Break/Make

Select Make/Break
Select Break/Make

Select Break/Make
De-select Make/Break

Select Make/Break
De-select Break/Make

Make/Break
Break/Make

Break/Make
Don't Care

Make/Break
Don't Care

The optional light pen can be used to toggle the LED states
directly. The light pen can also select ro ws for make/break or
break/make operation from slave units. The row selection is
in effect for all units connected in a master/slave
configuration.

4.11 Triggering

When a Model 707A stand-alone or master unit is triggered,
the stored relay setup from RELAY STEP+1 is sent to the
relays. Triggers are enabled with the front panel ENABLE
key of the TRIGGER group (see Figure 4-15). This key tog­gles between triggers enabled and triggers disabled. When
triggers are enabled, the ENABLE LED is lit.

TRIGGER

ENABLE

SOURCE

MANUAL

Figure 4-15

Trigger keys

4.11.1 T rigger sources

The programmed trigger source provides the stimulus to
increment to the next stored setup. Trigger sources include:

• Front panel MANUAL key — When triggers are
enabled, this key is always operational (on stand-alone
and master units) regardless of the selected source
(unless the unit is placed in remote over the IEEE-488
bus).

• External trigger pulse — An appropriate pulse, applied
to the EXTERNAL TRIGGER INPUT jack on the rear
panel, provides the trigger stimulus.

• IEEE command triggers — IEEE-488 GET, X, or talk
commands provide the stimulus when the appropriate
source is selected.

Select the trigger source as follows:

1. Press SOURCE and note that the current trigger source
is displayed:

TRIG ON EXT

This is the display for external triggering (the power-up
default). Table 4-8 lists the displays for all trigger
sources.

2. Press the SCROLL or keys until the desired trigger
source is displayed. Then press ENTER to select it and
exit menu mode.

3. If another source is scrolled to before pressing ENTER,
pressing CANCEL once returns the old selection, press­ing it again exits menu mode.

Table 4-8

Front panel messages for trigger sources

Message Description 1

TRIG ON TALK
TRIG ON GET
TRIG ON X
TRIG ON EXT
TRIG ON KEY

IEEE talk command
IEEE GET command
IEEE X command
External trigger pulse
Front panel MANUAL key
only*

The maximum trigger rate is specified with no make/break or
break/make rows selected. As will be described in paragraph

4.11.3, additional switching delays are necessary with make/
break or break/make operation.

4-20

*If triggers are enabled, pressing MANUAL emulates the selected trigger
source.

Operation

4.11.2 Front panel triggering

T o trigger the Model 707A from the front panel, simply press
the MANUAL key. (Press and hold for auto-repeat.) If trig­gers are enabled, this key is always operational regardless of
the selected trigger source (unless the unit is placed in
remote over the IEEE-488 bus, in which case all front panel
keys except LOCAL are locked out). Thus, front panel trig­ger source selection (TRIG ON KEY) provides a means to
lock out all other trigger sources when only front panel trig­gering is desired.

Triggering will stop when the RELAY STEP field incre­ments to 100. If you press MANUAL and the unit is not
ready, an error message will be displayed, as discussed in the
following paragraph.

4.11.3 T rigger overrun conditions

Once the instrument is triggered, it begins transferring relay
setup data from mainframe memory to the matrix cards. If a
second trigger is received while the unit is still transferring
data, a trigger overrun condition will occur. In this case, the
second trigger is not processed and the unit will display the
following error message:

TRIG OVERRUN

After the time required for transferring relay data has
elapsed, the Model 707A is able to process another trigger. If
a trigger is received before the programmed settling time has
elapsed, the following message is displayed:

NOT SETTLED

Figure 4-16 shows an example setup change and a timing
diagram of the READY (for trigger) pulse and a high true
MA TRIX READ Y pulse when the Model 707A is processing
the trigger. (The status of these signals is available in the
serial poll byte, see Section 5.) This timing is for setups with
no make/break or break/make rows.

1. Closes crosspoints in make/break rows yielding an
intermediate setup.

2. Opens crosspoints in make/break rows and opens/closes
crosspoints in “don't care” rows yielding the desired
setup.

If only break/make rows are selected, the Model 707A takes
these steps:

1. Opens crosspoints in break/make rows yielding an inter­mediate setup.

2. Closes crosspoints in break/make rows and opens/closes
crosspoints in “don't care” rows yielding the desired
setup.

An example of these operations is shown in Figure 4-17 with
its corresponding timing diagram. By comparing Figures
4-16 and 4-17, you can see that the intermediate setup
needed for make/break or break/make causes a delay in the
assertion of READY and MATRIX READY equal to the
relay settling time.

When a combination of make/break and break/make rows
are selected, the Model 707A must switch through three
intermediate setups to ensure proper relay operation. The
steps taken by the unit are as follows:

1. Opens crosspoints in break/make rows yielding the first
intermediate setup.

2. Closes crosspoints in make/break rows yielding the sec­ond intermediate setup.

3. Opens crosspoints in make/break rows yielding the third
intermediate setup.

4. Closes crosspoints in break/make rows and opens/closes
crosspoints in “don't care” rows yielding the desired
setup.

Figure 4-18 shows an example setup change with the neces­sary intermediate setups. As the timing diagram sho ws, three
additional relay settling time intervals are needed for the
intermediate setups.

When either make/break or break/make operation is
selected, but not both, the Model 707A switches through an
intermediate setup to ensure proper relay operation. If only
make/break rows are selected, the Model 707A takes these
steps:

4-21

Operation

State :

Don't Car e

Actions :

Ready

Matrix
Ready

Additional Trigger
not Processed

Setup N Commands

123 12 3

AA

XX X X

Open Don't Car e

Close Don't Care

Setup Data

Shift

Relay

Settling Time

TRIG

OVERRUN

NOT SETTLED Message

Additional Trigger I s P r oc es s ed

Setup N + 1

NA2
CA3

Programmed
Settling Time

Figure 4-16

Timing without make/break or break/make rows

4-22

Operation

State : Setup N

123 123 123

Make/Break

Don' t Car e

Act ions : Close Make/Br eak Open Make/Break

Break/Make

Don't Car e

Actions :

A

B

Setup N Inter m ediate

123 123 123

A

B

Open Break/ M ak e Close Break/M ak e

Setup Data

Shift

Relay

Settling Time

Int er m ediate

Setup

A

BB

Open Don't Car e

Close Don't Care

Setup

A

BB

Open Don't Car e

Close Don't Care

Setup Data

Shift

Relay

Settling Time

Setup N + 1

A

Setup N+ 1

A

Commands

NA2, B 2
CA3, B 3

Make/ B r eak Operation

Break/Break Operation

Commands

NA,2 B2
CA3, B 3

Programmed

Settling Time

Ready

Matrix
Ready

TRI G OVERRUN

Additional Trigger

Not Processed

Figure 4-17

Timing with either make/break or break/make rows

Error

NOT SETTLED

Message

Additional Trigger

is Processed

4-23

Operation

State: Intermediate

123 123 123 123 123

Make/Break

Break/Make
Don't Car e

Actions:

Ready

Matrix

Ready

AA

B
C

Open Break/ M ak e Close Make/Br eak Open Make/Break Close Break/M ak e

Setup Data

Shift

Relay

Setup A

B
C

Setup Data

Shift

Relay Relay

Settling Time Settling Time Settling Time

TRI G OVERRUN Error

Additional Trigger not P r oc es s ed

Int er m ediate

Setup B

A
BB
C

Setup Data

Shift

Int er m ediate

Setup C

AA

CC

Setup Data

Shift

Relay Programmed

Setup N+ 1Setup N

Commands

NA2, B 2, C2

CA3 , B3, C3

B

Open Don't Car e

Close Don't Care

Settling TimeSettling Time

NOT SETTLED Message
Additional Trigger is P r oc es s ed

Figure 4-18

Timing with both make/break and break/make rows

4-24

Operation

4.11.4 External trigger input

To use external triggering, first select that source with the
MENU and SCROLL keys as described in paragraph 4.11.1.
With triggers enabled, the unit will then be triggered when an
input pulse with the specifications previously shown in Fig­ure 4-10 is applied to the EXTERNAL TRIGGER INPUT
jack. The unit is triggered on either the falling (1eading) or
rising (trailing) edge of the pulse, as selected by a menu item.

4.11.5 Matrix ready output

The matrix ready output provides a TTL-compatible signal,
as shown previously in Figure 4-11. This signal can be used
to inform other instruments when the total settling time is
complete. It is programmable by a menu item for high or low
true. The leading edge of the “true” level indicates the end of
the total settling time (relay settling time plus programmed
settling time).

4.11.6 IEEE-488 bus triggering

To trigger a setup change with an IEEE-488 trigger source,
you must send the appropriate IEEE-488 command over the
bus: X, talk, or GET depending on the selected source. T rig­ger on GET allows the fastest IEEE-488 triggering response.
See Section 5 for details on bus triggering.

If one of these commands has been selected as the trigger
source, you can also trigger the unit by pressing the MAN­UAL key unless the unit is in remote.

4.12 Resetting

The reset operation performs the same functions as cycling
power except power -up self-checking. If a master/sla ve error
is detected during reset, the unit will revert to stand-alone
operation. The front panel RESET key is used to initiate a
reset operation.

Reset, power-up, and factory default conditions were previ­ously listed in Table 4-2.

4-25

5

IEEE-488 Programming

5.1 Introduction

This section contains information on programming the
Model 707A over the IEEE-488 bus. Detailed instructions
for all programmable functions are included. However,
information concerning operating modes presented else­where are not repeated.

5.2 IEEE-488 quick start

The following paragraphs provide a step-by-step procedure
for putting a Model 707A on the bus to program some basic
commands.

Step 1: Connect the Model 707A to the controller

With power off, connect the Model 707A to the IEEE-488
interface of the controller using a standard interface cable.
Some controllers include an integral cable; others require a
separate cable. Paragraph 5.3 discusses bus connections in
detail.

Step 2: Select the primary address

The primary address is a way for the controller to refer to
each device on the bus individually. Consequently, the pri­mary address of your Model 707A must be the same as the
primary address specified in the controller's programming
language, or you cannot program the instrument. Each
device on the bus must have a different primary address.

The primary address of your Model 707A is set to 18 at the
factory, but you can set the address to values between 0 and
30 for a stand-alone unit, or 31 and 60 for a master in a mas­ter/slave loop (refer to paragraph 5.5).

Step 3: Write your program

All operations require a simple program to send commands
to the instrument. Figure 5-1 shows a flowchart of a program
to select make/break and break/make rows, modify cross­points of a setup stored in memory, send the setup to the
relays, and then request data of the present relay setup.

The corresponding program (written in MS QBASIC sup­plied with MS-DOS 5.0 and later) is contained in three parts
for this example. The program assumes a primary IEEE-488
address of 18 for the Model 707A and that power-up default
conditions exist in the unit.

5-1

IEEE-488 Programming

Sample Program Comments

DIM A$[200],C$[200] ' Dimension crosspoint input and display.
PRINT #1, "REMOTE 18" ' Tell Model 707A (at IEEE-488 location 18) to

' listen over bus.

PRINT #1, "OUTPUT 18;V11000000W00000011X" ' Select rows A and B for make/break and rows

' G and H for break/make.

PRINT #1, "OUTPUT 18;E1Z1,0X" ' Set edit pointer to setup #1, and send setup #1
COMMAND: ' to relays and display.
LINE INPUT "CROSSPOINTS COMMAND", C$ ' Allow user to input crosspoint data.
IF LEN (C$)=0 THEN STOP ' Check for null string.
PRINT #1, "OUTPUT 18;C$+"X" ' Send command string to Model 707A.
GOTO COMMAND ' Allow user to input additional crosspoint data.
END

Start

Place Unit in Rem ote

Select Make/Break
and Break/Make Rows

Set Edit Pointer to Setup
Memory

Open and Close
Crosspoints of S etup

Get Set up and Dis play

Trigger S etup to
Relays

End

Step 4: Open and close crosspoints

You can open, close, and clear crosspoints by sending the
appropriate command, which is made up of an ASCII letter
representing the command, followed by one or more charac­ters for the command options. Commands can be grouped
together in one string. The command strings are not opening
and closing relays unless the edit pointer is set to zero.

To open and close crosspoints over the bus, run the previous
program and enter a command string when prompted. Some
example strings are shown in Table 5-1.

Terminate each string by pressing RETURN on the control­ler keyboard. If a null string is entered, the program ends.

Table 5-1

Sample strings

Sample string Description

"P1"

Clear (open) all crosspoints of
setup #1.

"CA5,A6,B9,B10"

Set (close) crosspoints A5, A6,
B9, B10.

"NA5,A6"
"CA1,A2NB9,B10"

Clear (open) crosspoints A5, A6.
Set (close) A1, A2 and clear
(open) B9, B10.

Figure 5-1

Flowchart of example program

5-2

IEEE-488 Programming

Step 5: Modify program for requesting data

To display or print setup data, you must specify one of the
data output formats that sends ASCII characters. Note that a
variety of data formats are available, as discussed in para­graph 5.9. The data can be a setup stored in memory or the
present relay setup. Modify the previous sample program
with the following statements. Add the statements immedi­ately before the GOTO line.

PRINT #1, "OUTPUT 18;
U2,1G2X"
PRINT #1, "ENTER 18"
LINE INPUT #2, A$
PRINT A$

' Set data format for setup #1.

' Get stored setup data
' and print.

When the program is run with these statements, it lists the
closed crosspoints that you have entered.

Step 6: Modify program for triggering

Triggers provide a quick way for copying relay data from a
pre-programmed setup to the relays. Each valid trigger
causes the next sequential setup to be copied to the relays and
the relay pointer to be updated.

Modify the previous sample program with the following
statements. Add the statements immediately before the END
line.

5-2. Two screws are located on each connector to ensure that
connections remain secure. Present standards call for metric
threads, as identified by dark colored screws. (Earlier ver­sions had silver colored screws. Do not use these connectors
with the Model 707A.)

Figure 5-2

IEEE-488 connector

A typical connecting scheme is shown in Figure 5-3. Each
cable normally has a standard connector on each end. These
connectors are designed to be stacked to allow a number of
parallel connections on one instrument. To avoid possible
damage, do not stack more than three connectors on any one
instrument.

PRINT "PRESS ANY KEY TO
CONTINUE"
DO
LOOP WHILE INKEY$=" "
PRINT #1, "OUTPUT
18;F1T2X"
PRINT #1,"TRIGGER 18"

' Wait for keypress.

' Enable triggers, select
' trigger-on GET.

' Trigger setup #1 to
' relays.

When any key on the keyboard is pressed, this program mod­ification triggers setup #1 to the relays. This is because the
relay step pointer, which is different from the edit pointer,
was set to zero by power-up.

5.3 Bus cable connections

The following paragraphs provide information needed to
connect instrumentation to the IEEE-488 bus. The Model
707A is connected to the IEEE-488 bus through a cable
equipped with standard IEEE-488 connectors. See Figure

Instrument

Figure 5-3

IEEE-488 connections

Instrument

Model 707

Controller

5-3

IEEE-488 Programming

NOTE

To minimize interference caused by elec­tromagnetic radiation, use only shielded
IEEE-488 cables. The Model 7007-1 and
7007-2 shielded IEEE-488 cables are
available from Keithley Instruments.

Connect the cable to the Model 707A as follows:

1. Line up the connector on the cable with the connector on
the rear panel of the instrument. Figure 5-4 shows the
IEEE-488 connector location.

2. Tighten screws securely, but do not overtighten them.
(Overtightening can break the connector.)

3. Add additional connectors from other instruments, as
required.

4. Make sure the other end of the cable is properly connect­ed to the controller. Some controllers ha v e an IEEE-488
type connector, while others do not. Consult the instruc­tion manual of your controller for the proper connecting
method.

NOTE

The IEEE-488 bus is limited to a maxi­mum of 15 devices, including the control­ler. Also, the maximum cable length is
limited to 20 meters, or 2 meters multi­plied by the number of devices, whichever
is less. Failure to observe these limits may
result in erratic bus operation.

In master/slave configurations, only the
master unit is connected to the IEEE-488
bus. If slave units are also connected, er­ratic bus operation results. Custom cables
may be constructed by using the contact
assignments listed in Table 5-2 and shown
in Figure 5-5.

Figure 5-4

IEEE-488 connector location

5-4

IEEE-488 Programming

Table 5-2

Contact assignments

Contact

Number

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24

*Number in parentheses refers to the signal ground

return of reference contact number. EOI and REN sig­nal lines return on contact 24.

designation IEEE-488 type

1

DIO1

2

DIO2

3

DIO3

4

DIO4

5

EOI (24)*

6

DA V

7

NRFD

8

NDAC

9

IFC
SRQ
ATN
SHIELD
DIO5
DIO6
DIO7
DIO8
REN (24)*
Gnd, (6)*
Gnd, (7)*
Gnd, (8)*
Gnd, (9)*
Gnd, (10)*
Gnd, (11)*
Gnd, LOGIC

Data
Data
Data
Data
Management
Handshake
Handshake
Handshake
Management
Management
Management
Ground
Data
Data
Data
Data
Management
Ground
Ground
Ground
Ground
Ground
Ground
Ground

5.4 Interface function codes

The interface function codes, which are part of the IEEE­488 standards, define an instrument's ability to support
various interface functions. They should not be confused
with programming commands found elsewhere in this
manual. Interface function codes for the Model 707A are
listed in Table 5-3. The codes define Model 707A
capabilities as follows:

SH1 (Source Handshake) — SH1 defines the ability of the

Model 707A to properly handshake data or command bytes
when the unit is a source.

AH1 (Acceptor Handshake) — AH1 defines the ability of

the Model 707A to properly handshake the bus when it is an
acceptor of data or commands.

T6 (Talker) — The ability of the Model 707A to send data

over the bus to other devices is defined by the T6 function.
Model 707A talker capabilities exist only after the instru­ment has been addressed to talk. T6 means that the Model
707A is a basic talker, has serial poll capabilities, and is
unaddressed to talk when it receives its own listen address.

TE0 (Extended Talker) — The Model 707A does not have

extended talker capabilities.

L4 (Listener) — The L4 function defines the ability of the

Model 707A to receive device-dependent data over the bus.
Listener capabilities exist only after the instrument has been
addressed to listen. L4 means that the Model 707A is a basic
listener and is unaddressed to listen when it receives its own
talk address.

LE0 (Extended Listener) — The Model 707A does not have

extended listener capabilities.

CONTACT 12 CONTACT 1

CONTACT 13CONTACT 24

Figure 5-5

Contact assignments

SR1 (Service Request) — The SR1 function defines the

ability of the Model 707A to request service from the
controller.

RL1 (Remote Local) — The RL1 function defines the capa-

bilities of the Model 707A to be placed in the remote or local
states.

PP0 (Parallel Poll) — PP0 means that the Model 707A does

not have parallel polling capabilities.

DC1 (Device Clear) — The DC1 function defines the ability

of the Model 707A to be cleared (initialized).

DT1 (Device Trigger) — The ability for the Model 707A to

have setups triggered is defined by the DT1 function.

C0 (Controller) — The Model 707A has no controller

capabilities.

E1 (Bus Driver T ype) — The Model 707A has open-collec-

tor bus drivers.

5-5

IEEE-488 Programming

Table 5-3

Model 707A interface function codes

Code Interface function

SH1
AH1
T6

TE0
L4

LE0
SR1
RL1
PP0
DC1
DT1
C0
E1

1

MLA – My Listen Address.

2

MTA – My Talk Address

Source Handshake capability.
Acceptor Handshake capability.
Talker (basic talker, serial poll, unaddressed to
talk on MLA

1

).
No Extended Talker capabilities.
Listener (basic listener, unaddressed to listen on

2

MT A

).
No Extended Listener capabilities.
Service Request capability.
Remote Local capability.
No Parallel Poll capability.
Device Clear capability.
Device Trigger capability.
No Controller capability.
Open-collector bus drivers.

The primary address may be set to any value between 0 and
30 as long as address conflicts with other instruments are
avoided. Note that controllers are also given a primary
address, so do not use that address either. Most frequently,
controller addresses are 0 or 21, but you should consult the
controller’s instruction manual for details. Whatev er primary
address you choose, you must be certain that it corresponds
with the value specified as part of the controller’s program­ming language.

To check the present primary address, or to change to a new
one, perform the following procedure:

1. Press the MENU button until the current primary ad­dress is displayed. For example, if the instrument is set
to primary address 18, the following message is dis­played:

IEEE-488 18

2. To retain the current address, press CANCEL to exit
from the menu.

3. To change the primary address, use the numeric buttons
and press ENTER. This stores the new address in mem­ory so that the instrument powers up to that address.

5.5 Primary address programming

The Model 707A must receive a listen command before it
responds to addressed commands. Similarly, the unit must
receive a talk command before it transmits data. The Model
707A is shipped from the factory with a programmed pri­mary address of 18. The programming examples included in
this manual assume that address.

NOTE

Each device on the bus must hav e a unique
primary address. Failure to observe this
precaution will probably result in erratic
bus operation.

5-6

IEEE-488 Programming

5.6 QuickBASIC programming

Programming examples are written in Microsoft
QuickBASIC 4.5 using the Keithley KPC-488.2 (or Capital
Equipment Corporation) IEEE interface and the HP-style
Universal Language Driver (CECHP).

Before any programming example can be run, the Universal
Language Driver must be installed. To install the driver, enter
CECHP at the DOS prompt.

If you include the CECHP command in your
AUTOEXEC.BAT file, the driver will automatically be
installed each time you turn on your computer.

Table 5-4

BASIC IEEE-488 statements

Action Basic statement

Transmit string to device 18.
Obtain string from device 18.
Read string.
Display string.
Send GTL to device 18.
Send SDC to device 18.
Send DCL to all devices.
Send remote enable.
Cancel remote enable.
Serial poll device 18.
Send local lockout.
Send GET to device 18.
Send IFC.

Program fragments are used to demonstrate proper program­ming syntax. As the name implies, only a fragment of the
whole program is used to avoid redundancy . At the be ginning
of each program, driver files must be opened. The input ter­minator should be set for CRLF. For example:

OPEN “ieee” FOR OUTPUT AS #1
OPEN “ieee” FOR INPUT AS #2
PRINT #1, “interm crlf”

A partial list of BASIC statements is shown in Table 5-4.

PRINT #1, "OUTPUT 18",A$
PRINT #1, "ENTER 18"
LINE INPUT #2, A$
PRINT A$
PRINT #1, "LOCAL 18"
PRINT #1, "CLEAR 18"
PRINT #1, "CLEAR"
PRINT #1, "REMOTE"
PRINT #1, "LOCAL"
PRINT #1, "SPOLL(18)"
PRINT #1, "LOCAL LOCKOUT"
PRINT #1, "TRIGGER 18"
PRINT #1, "ABORT"

5-7

IEEE-488 Programming

5.7 Front panel aspects of IEEE-488 operation

The following paragraphs discuss aspects of the front panel
that are part of IEEE-488 operation, including front panel
error messages, IEEE-488 status indicators, and the LOCAL
key.

5.7.1 Front panel error messages

The Model 707A has a number of front panel messages asso­ciated with IEEE-488 programming. These messages, which
are listed in Table 5-5, inform you of certain conditions that
occur when sending device-dependent commands to the
instrument.

The following paragraphs describe the front panel error mes­sages associated with IEEE-488 programming. Note that the
instrument may be programmed to generate an SRQ, and U
command status words can be checked for specific error con­ditions if any of these errors occur. See paragraphs 5.9.14
and 5.9.22.

Table 5-5

Front panel IEEE-488 error messages

Type of error Description

CARD ID ERROR

IDDC

IDDCO

M/S ERROR

NOT IN REMOTE

NOT SETTLED

RAM FAIL

ROM FAIL

SETUP ERROR

TRIG OVERRUN

Power-up routine cannot iden­tify one or more cards.
Illegal device-dependent com­mand received.
Illegal device-dependent com­mand option received.
Master/slave communication or
timing error.
X received while unit is in
LOCAL state.
Unit triggered before total set­tling time expired.
Power-up routine or self-test
detected RAM error.
Power-up routine or self-test
detected program ROM check­sum error.
Power-up routine detected
checksum errors in one or more
setups. (Affected setups are
cleared.)
Unit triggered before Ready bit
is set.

Card identification error

A card ID error occurs when the instrument's power-up rou­tine detects a checksum error in the information from a card.
When in master/slave configuration, the cards in error are
indicated by all LEDs in their crosspoint display blocks
being lit.

IDDC (illegal device-dependent command) error

An IDDC error occurs when the unit receives an illegal
device-dependent command over the bus. For example, the
command string 1X includes an illegal command because
the “1” is not part of the instrument's programming language.

NOTE

When an IDDC error is detected in a com­mand string, all commands in the string,
up to and including the next X, are ig­nored.

To correct the error condition, send only valid commands.
Refer to paragraph 5.9 for device-dependent command pro­gramming details. An IDDC error is flagged in the U1 word,
as discussed in paragraph 5.9.22.

IDDCO (illegal device-dependent command option)
error

Sending the instrument a legal command with an illegal
option results in an IDDCO error.

For example, the command K9X has an illegal option (9) that
is not part of the instrument's programming language. Thus,
although the command K is valid, the option is not, and the
IDDCO error results.

NOTE

When an IDDCO error is detected in a
command string, all commands in the
string, up to and including the next X, are
ignored.

To correct this error condition, use only valid command
options, as discussed in paragraph 5.9. An error is flagged in
the U1 word, as discussed in paragraph 5.9.22.

Master/slave error

A master/slave error occurs when a communication or
timing error is detected in the closed loop of units. If one or
more errors are detected, the message M/S ERROR is
displayed.

5-8

IEEE-488 Programming

T o simulate the error condition, disconnect a DIN cable from
either of the MASTER/SLAVE connectors. The condition is
detected when the Model 707A performs the next operation
that requires communication among the units. A master/
slave error is flagged in the U1 word, as discussed in para­graph 5.9.22.

Not in remote error

A not in remote error occurs if the instrument receives an
“X” while it is in the local state. This is caused by failing to
set the REN line true before addressing the Model 707A to
listen. A not in remote error is flagged in the U1 word, as dis­cussed in paragraph 5.9.22.

Not settled error

A trigger before settling time error occurs when the instru­ment receives an additional trigger before the settling time
has expired. This time period is after assertion of the
READY signal and before assertion of the MATRIX
READY signal. See paragraph 5.8 for a complete discussion
of trigger timing. Both READY and MATRIX READY are
bits in the SPOLL byte; MATRIX READY is also a rear
panel signal. Note that a master/slave error is also flagged in
the U1 word, as discussed in paragraph 5.9.22.

A trigger during this time period is processed normally.

RAM or ROM failure

A RAM or ROM failure occurs when the power-up routine
detects an error, either a RAM error or a checksum error in
program ROM. If an error is detected, a RAM FAIL or ROM
FAIL message is displayed (cleared by any keypress).

Setup error

A setup error occurs when the Model 707A power-up routine
detects a checksum error in one or more setups stored in non­volatile memory. If an error is detected, SETUP ERROR is
displayed and the affected setups are cleared to all open. A
keypress will clear this error. Note that a setup error is also
flagged in the U1 word, as discussed in paragraph 5.9.22.

Trigger overrun (hardware) error

A trigger overrun occurs when the instrument is triggered
while it is still processing a setup change from a previous
trigger and before the READY (for trigger) signal is asserted.
READY is a bit in the SPOLL byte. See paragraph 5.8 for a
complete discussion of trigger timing. The exact trigger
stimulus depends on the selected trigger source, as discussed
in paragraph 5.9.21.

Overrun triggers do not affect the instrument except to gen­erate the error. In other words, the present setup change is not
aborted by the overrun trigger stimulus, and the trigger is
ignored. Note that a trigger overrun error is also flagged in
the U1 word, as discussed in paragraph 5.9.22.

5.7.2 Status indicators

The TALK, LISTEN, and REMOTE indicators show the
present IEEE-488 status of the instrument. Each of these
indicators is described below.

TALK

LISTEN

REMOTE

Figure 5-6

IEEE-488 indicators

TALK — This indicator is on when the instrument is in the

talker active state. The unit is placed in this state by address­ing it to talk with the correct MTA (My Talk Address) com­mand. TALK is off when the unit is in the talker idle state.
The instrument is placed in the talker idle state by sending it
an UNT (Untalk) command, addressing it to listen, or with
the IFC (Interface Clear) command.

LISTEN — This indicator is on when the Model 707A is in

the listener active state, which is activated by addressing the
instrument to listen with the correct MLA (My Listen
Address) command. Listen is off when the unit is in the lis­tener idle state. The unit can be placed in the listener idle
state by sending UNL (Unlisten), addressing it to talk, or by
sending IFC (Interface Clear) over the bus.

REMOTE — This indicator shows when the instrument is in

the remote state. Note that REMOTE does not necessarily
indicate the state of the REN line, as the instrument must be
addressed to listen with REN true before the REMOTE indi­cator turns on. When the instrument is in remote, all front
panel keys except for the LOCAL key are locked out. When
REMOTE is turned off, the instrument is in the local state,
and front panel operation is restored.

5-9

IEEE-488 Programming

5.7.3 LOCAL key

The LOCAL key cancels the remote state and restores local
operation of the instrument.

LOCAL

Figure 5-7

LOCAL key

Since all front panel keys except LOCAL are locked out
when the instrument is in remote, this key provides a
convenient method of restoring front panel operation.
Pressing LOCAL also turns off the REMOTE indicator, and
returns the display to normal if a message was displayed with
the D command. (See paragraph 5.9.5)

Note that the LOCAL key is inoperative if the LLO (Local
Lockout) command is in effect.

1. All front panel keys except for LOCAL are inoperative
while the Model 707A is in remote (REMOTE on). The
unit is placed in remote by addressing it to listen with
the REN line true. Thus, to control the unit from the
front panel, it is necessary to press LOCAL after pro­gramming over the bus. Note that LOCAL is also inop­erative if the LLO (Local Lockout) command is in
effect.

2. Front panel parameter modification should always be
completed before attempting to use bus control. For
example, you should not attempt to program a setup
over the bus while editing a setup from the front panel.

5.8 General bus command programming

5.8.1 Overview

General bus commands are those commands (such as DCL)
that have the same general meaning regardless of the instru­ment. Commands supported by the Model 707A are listed in
Table 5-8, which also lists BASIC statements necessary to
send each command. Note that commands requiring that a
primary address be specified assume that the Model 707A
primary address is set to 18 (its factory default address).

5.7.4 Concurrent front panel and bus operation

Fundamentally, there is no reason why you cannot control
the instrument simultaneously from the front panel and over
the IEEE-488 bus. However, the following points should be
kept in mind.

5.8.2 REN (remote enable)

The remote enable command is sent to the Model 707A by
the controller to set up the instrument for remote operation.
Generally, the instrument should be placed in the remote
state before you attempt to program it over the bus. Setting
REN true does not actually place the instrument in the
remote state. Instead the instrument must be addressed to lis­ten after setting REN true before it goes into remote.

5-10

Table 5-6

General bus commands/BASIC statements

Command Basic statement Effect on Model 707A

REN
IFC
LLO
GTL
DCL
SDC
GET

PRINT #1, "REMOTE"
PRINT #1, "ABORT"
PRINT #1, "LOCAL LOCKOUT"
PRINT #1, "LOCAL 18"
PRINT #1, "CLEAR"
PRINT #1, "CLEAR 18"
PRINT #1, "TRIGGER 18"

Goes into effect when next addressed to listen.
Goes into talker and listener idle states.
LOCAL key locked out.
Cancel remote, restore front panel operation.
Return to default conditions.
Return to default conditions.
Triggers setup with GET source.

IEEE-488 Programming

NOTE

The instrument need not be in remote to be
a talker. All front panel controls (except
LOCAL and POWER) are inoperative
while the instrument is in remote. You can
restore normal front panel operation by
pressing the LOCAL key.

5.8.3 IFC (interface clear)

The IFC command is sent by the controller to place the
Model 707A in the local, talker, and listener idle states. The
unit responds to the IFC command by canceling front panel
TALK or LISTEN lights, if the instrument was previously
placed in one of those states.

5.8.4 LLO (local lockout)

The LLO command is used to prevent local operation of the
instrument. After the unit recei v es LLO, all of its front panel
controls except POWER are inoperative.

mand, so all instruments equipped to implement DCL will do
so simultaneously. When the Model 707A receives a DCL
command, it returns to the power-up default conditions. DCL
does not affect the programmed primary address.

5.8.7 SDC (selective device clear)

The SDC command is an addressed command that performs
essentially the same function as the DCL command. How­ever since each device must be individually addressed, the
SDC command provides a method to clear only selected
instruments instead of clearing all instruments simulta­neously, as is the case with DCL. Any devices on the bus that
are addressed to listen are cleared. When the Model 707A
receives the SDC command, it returns to the power-up
default conditions.

5.8.8 GET (group execute trigger)

GET may be used to initiate a Model 707A setup change if
the instrument is placed in the appropriate trigger source.
Refer to paragraph 5.9 for more information on triggering.

5.8.5 GTL (go to local)

The GTL command is used to take the instrument out of the
remote state. Operation of the front panel keys will also be
restored by GTL unless LLO is in effect. To cancel LLO, you
must set REN false.

5.8.6 DCL (device clear)

The DCL command may be used to clear the Model 707A
and return it to its power-up default conditions (see Table
5-2). Note that the DCL command is not an addressed com-

5.8.9 SPE, SPD (serial polling)

The serial polling sequence is used to obtain the Model 707A
serial poll byte. The serial poll byte contains important infor­mation about internal functions, as described in paragraph

5.9.14. Generally, the serial polling sequence is used by the
controller to determine which of several instruments has
requested service with the SRQ line. However, the serial
polling sequence may be performed at any time to obtain the
serial poll byte from the Model 707A.

5-11

IEEE-488 Programming

Table 5-7

Factory default, power-up, and DCL/SDC conditions

Parameter Factory default Power-up, DCL/SDC Description

Relays
Stored Setups
Relay Step
Memory Step
Master/Slave
IEEE-488 Address
External Trigger
Matrix Ready
Display
Edit Pointer
Trigger Enable
Data Format
EOI/Hold-off
SRQ
Digital Output
Programmed Settling Time
Trigger Source
Make/Break Rows
Break/Make Rows
Terminator

Notes:

1. The IEEE-488 address is not affected by the Restore (R0) command.

2. Units previously defined as stand-alone or slave will power up as stand-alone units. They become slave units when a master unit initial­izes a master/slave loop upon power up.

3. DCL/SDC does not affect master/slave state. DCL/SDC does clear slaves.

All opened
All cleared
000
001
Stand-alone
18 (Note 1)
A0
B0
DX
E0
F0
G0
K0
M0
O000
S0
T7
V00000000
W00000000
Y0

All opened
Not affected
000
001
(Notes 2, 3)
Not affected
A0
B0
DX
E0
F0
G0
K0
M0
O000
S0
T7
Not affected
Not affected
Y0

—
—
Point to relays
Point to setup 1
—
—
Falling edge triggers
Negative true
Normal alphanumeric display
Point to relays
Triggers disabled
Full output, all data sent in one talk
Both enabled
Disabled
Output lines low
0ms
External trigger
None selected
None selected
<CR><LF>

5.9 Device-dependent command (DDC) programming

5.9.1 Overview

IEEE-488 device-dependent commands control most instru­ment operating modes. All front panel modes (such as trigger
source and settling time), as well as some modes not avail­able from the front panel (like SRQ and terminator) can be
programmed with these commands.

Command syntax

Each command is made up of a single ASCII capital letter
followed by one or more numbers or letters representing an
option(s) of that command. For example, the trigger source
can be set over the bus by sending the letter “T” follo wed by
a number representing the trigger option. T1X would be sent
to trigger on talk. The IEEE-488 bus treats these commands
as data; they are sent with the ATN line false.

5-12

Some commands permit more than one option; these must be
separated with commas. For example, the close crosspoints
commands have the general format:

Crc(,rc)...(,rc)

Here the “rc” options are row and column addresses, while the
commas indicate the necessary delimiters. The parentheses
indicate that the option and associated delimiter are optional.

NOTE

Do not include parentheses in actual com­mand strings.

Multiple commands

A number of commands can be grouped together in one com­mand string, which is generally terminated by the “X” char­acter. This character tells the instrument to execute the
command or command string as described in paragraph

5.9.25. Commands sent without the X character are not exe-

cuted at that particular time, but they are stored within an
internal command buffer for later execution when the X
character is finally received.

IEEE-488 Programming

Table 5-8

Order of command execution

If a particular command occurs “n” times in a command
string, then the “nth” occurrence is the only one used (i.e.,
T0T2T4X appears to the Model 707A as T4X).

Invalid commands

If an invalid command is sent as part of the command string,
no commands in the string are executed. Under these condi­tions, the instrument displays a front panel error message
(IDDC or IDDCO), as described in paragraph 5.7, and it can
be programmed to generate an SRQ (Service Request), as
discussed in paragraph 5.9.14. Checking is done as syntacti­cal groups of characters are received.

Valid command strings (typical samples)

A0X Single command string.
A0T6X Multiple command string.
P 0X Space is ignored
Z15,0X Multiple-option command string (options sepa-

rated by commas).

Invalid command strings (typical samples)

1X Invalid command as 1 is not a valid command.
K7X Invalid command option as 7 is not a valid

option of the K command.

CA4OOX Invalid option (maximum column address is

60).

Z0100X Multiple-option command without the neces-

sary separating commas.

Order of command execution

Device-dependent commands are not necessarily executed in
the order received. Rather, each instrument always executes
them in a specific order. The order of execution for the Model
707A is summarized in Table 5-10. Note that the X com­mand is listed first since it is the character that forces the exe­cution of the rest of the commands.

If you wish to force a particular order of execution, include
the execute (X) character after each command option group­ing in the command string. For example, the following string
would be executed in the received order: T6XA1XR0X.

Order Command Description

1
2
3

X

R
L

Execute DDCs.
Restore factory default conditions.
Download setups from controller to

Model 707A.
4
5
6
7

E

I

Q

P

Set the edit pointer.

Insert a blank setup in memory.

Delete a setup from memory.

Clear all crosspoints at specified

setup.
8

Z

Copy a setup from memory or relays

to memory or relays.
9

10
11

V

W

N

Select rows from make/break.

Select rows for break/make.

Open crosspoints of setup indicated

by edit pointer.

12

C

Close crosspoints of setup indicated

by edit pointer.

13

A

Select trigger edge of External Trig-

ger pulse.

14

B

Select logic sense of Matrix Ready

signal.

15
16
17
18

D

F

G

J

Display a user message.

Enable/disable triggers.

Select data output format.

Execute ROM/RAM/display self-

test.

19
20
21
22
23
24
25
26

K

M

O

U
Y
H

Select EOI and hold-off on X.

Set the SRQ mask.

Set the digital output.

S
T

Program the settling time.

Select the trigger source.

Request status.

Select terminator characters.

Hit a front panel key.

Device-dependent command summary

All Model 707A device-dependent commands are summa­rized in Table 5-11, which also lists respective paragraphs
where more detailed information on each command may be
found.

5-13

IEEE-488 Programming

Table 5-9

DDC summary

Mode Command Description Para.

External Trigger

Matrix Ready

Close Crosspoint

Display

Edit Pointer

Enable/Disable Triggers

Data Format

Hit Key
Insert Blank Setup
Self-test
EOI and Hold-off

Download Setups
SRQ

Open Crosspoint

Digital Output
Clear Crosspoints

Delete Setup
Restore Defaults
Programmed Settling Time
Trigger

A0
A1
B0
B1
Crc(,rc)...(,rc)

Dcccccccccccccc
DX
E0
En
F0
F1
G0
G1
G2 or G3
G4
G5
G6
G7
Hn
In
J0
K0
K1
K2
K3
K4
K5
Lbbb..X
M0
M1
M2
M8
M16
M32
M128
Nrc(,rc)...(,rc)

Onnn
P0
Pn
Qn
R0
Sn
T0 or T1
T2 or T3
T4 or T5
T6 or T7
T8 or T9

Falling edge triggers Model 707A
Rising edge triggers Model 707A
Negative true Matrix Ready output
Positive true Matrix Ready output
Close crosspoints of setup indicated by edit pointer
(rows A-H, columns 1-360)
Display ASCII character (14 max)
Return alphanumeric display to normal
Point to present relay setup
Point to stored relay setup (1-100)
Disable triggers
Enable triggers
Full output, all data in one talk
Full output, one switching system row per talk
Inspect output, all data in one talk
Condensed output, all data in one talk
Condensed output, one switching system per talk
Binary output, all data in one talk
Binary output, one switching system per talk
Emulate front panel key press (1-41)
Insert blank setup in memory (1-100)
Perform self-test
Send EOI, hold-off on X until Ready
No EOI, hold-off on X until Ready
Send EOI, do not hold-off on X
No EOI, do not hold-off on X
Send EOI, hold-off on X until Matrix Ready
No EOI, hold-off on X until Matrix Ready
Download setups from controller to Model 707A
SRQ disabled
Not used
Not used
Matrix Ready
Ready for trigger
Error
Not used
Open crosspoints of setup indicated by edit pointer
(rows A-H, columns 1-360)
Set states of digital output lines (000-255)
Open all crosspoint relays
Clear all crosspoints of stored setup (1-100)
Delete setup from memory (1-100)
Restore factory defaults
Program settling time in milliseconds (0-65000)
Trigger on talk
Trigger on GET
Trigger on X
Trigger on External Trigger pulse
Trigger on front panel MANUAL key only

5.9.2

5.9.3

5.9.4

5.9.5

5.9.6

5.9.7

5.9.8

5.9.9

5.9.10

5.9.11

5.9.12

5.9.13

5.9.14

5.9.15

5.9.16

5.9.17

5.9.18

5.9.19

5.9.20

5.9.21

5-14

IEEE-488 Programming

Table 5-9 (cont.)

DDC summary

Mode Command Description Para.

Status

Make/Break

Break/Make

Execute
Terminator

Copy Setup

U0
U1
U2,s
U3
U4
U5,u
U6
U7
U8
Vabcdefgh

Wabcdefgh

X
Y0
Y1
Y2
Y3
Z0,n
Zn,0
Zm,n

Send machine status word
Send error status word
Output setup “s” (0-100) with present G format
Send RELAY STEP pointer
Send number of slaves
Send model number of each card in unit “u” (0-4)
Send relay settling time
Send digital input of unit (0-65535)
Send RELAY TEST input
Select rows for make/break operation (abcdefgh = 00000000
to 11111111)
Select rows for break/make operation (abcdefgh = 00000000
to 11111111)
Execute commands
<CR><LF>
<LF><CR>
<CR>
<LF>
Copy present relay setup to memory location “n” (1-100)
Copy setup from memory location “n” (1-100) to relays
Copy setup from location “m” (0-100) to location “n” (0-100)

5.9.22

5.9.23

5.9.24

5.9.25

5.9.26

5.9.27

5-15

IEEE-488 Programming

5.9.2 A — External trigger

Purpose To select which edge of an external trigger pulse initiates a trigger.

Format An

Parameters n=0 Falling edge triggers Model 707A

n =1 Rising edge triggers Model 707A

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument def aults to A0

(falling edge).

Description The An command lets you program the Model 707A for triggering on a TTL-compatible f alling

or rising edge signal at the External Trigger input jack. A trigger signal increments the RELAY
STEP pointer and copies the setup indicated by the new value from memory to the relays.

Figure 5-8 shows example trigger pulses. Trigger on external must be the selected source
(T command), and triggers must be enabled (F command).

Programming note For information on the hardware this command is used with, refer to paragraph 4.11.

Example PRINT #1, “OUTPUT 18;A1X” ' Select rising edge pulse to trigger

PRINT #1, “OUTPUT 18;A0X” ' Select falling edge to trigger

TTL High

(3.4V Typical )

TTL Low

( 0.25V Typical )

TTL High

(3.4V Typical )

TTL Low

( 0.25V Typical )

Falling

Edge

600nsec

Minimum

A. FALLING EDGE OF PULSE

Rising

Edge

600nsec

Minimum

5-16

B. RISING EDGE OF PULSE

igure 5-8

xternal trigger pulse

IEEE-488 Programming

5.9.3 B — Matrix ready

Purpose To select the logic sense of the rear panel Matrix Ready signal.

Format Bn

Parameters n=0 Negative true Matrix Ready output

n=1 Positive true Matrix Ready output

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument def aults to B0

(negative true).

Description The B command lets you program the TTL-compatible Matrix Ready output as a high- or low-

true signal. This signal goes false when the relays are switched; it goes true after completion of
the (hardware) relay settling time and (user) programmed settling time. Figure 5-9 shows exam­ple Matrix Ready signals.

Programming notes 1. The Matrix Ready signal is negated by anything that causes a change to a relay state even if

no relays actually change state (e.g., closing an already closed relay).

2. Changing the logic sense of the Matrix Ready signal does not change the logic sense of the
Matrix Ready bit in the serial poll byte.

Example PRINT #1, “OUTPUT 18;B1X” ' Select positive true Matrix Ready

PRINT #1, “OUTPUT 18;B0X” ' Select negative true Matrix Ready

TTL High

( 3.4V Typical )

TTL Low

( 0.25V Typical )

TTL High

(3.4V Typical )

TTL Low

( 0.25V Typical )

Relay Settling Time +

Program m ed S ettling T im e

A. MATRIX READY HIGH TRUE

Relay Settling Time +

Program m ed S ettling T im e

B. MATRIX READY LOW TRUE

igure 5-9

atrix ready pulse

5-17

IEEE-488 Programming

5.9.4 C — Close crosspoint

Purpose To close crosspoints in a setup.

Format Crc(,rc)...(,rc)

Parameters r = A to H Row designation of crosspoint

c = 1 to 360 Column designation of crosspoint (360 with maximum of five Model 707A units)

Description The C command closes crosspoints in the setup indicated by the edit pointer. If the edit pointer

indicates the present relay setup (zero), the specified crosspoint relays are closed immediately.
If the edit pointer indicates a setup stored in memory (1-100), the specified crosspoints are set.

Programming notes 1. Do not include parentheses in command strings. They indicate that the option and associated

comma delimiter are optional.

2. Up to 25 crosspoints per mainframe can be specified in one close command (with a master
and four slaves, the limit is 125 crosspoints). In the same command string, up to 25 cross­points per mainframe can be opened. If either limit is exceeded, an IDDCO results.

3. The maximum value of the column parameter depends on the configuration (72 for stand­alone, 360 for master with four slave units). An IDDCO results if the maximum value is
exceeded.

4. This command is equivalent to multiple light pen operation(s).

Example PRINT #1, “OUTPUT 18;CA55X” ' Close one crosspoint

PRINT #1, “OUTPUT 18;CA55,A56,B49,B50X” ' Close multiple crosspoints

5.9.5 D — Display

Purpose To write messages on the front panel alphanumeric display of a stand-alone or master unit.

Format Dcccccccccccccc

Parameters c = ASCII character (14 maximum)

Default Upon power-up, or after receiving a DCL, SDC, or R0X command, the instrument defaults to

DX (return alphanumeric display to normal operation).

Description The D command allows you to display messages on the front panel alphanumeric display of a

stand-alone or master Model 707A. To send a message, simply follow the D command with
appropriate ASCII characters. Many displayable ASCII characters can be sent, including num­bers or upper case characters. Characters that can be displayed include: 0-9, A-Z, arithmetic and
most punctuation symbols.

Programming notes 1. As with other device-dependent commands, the D command string should be terminated with

the X.

2. Spaces in the command string are displayed.

3. The maximum number of characters is 14; any extra characters in the string are ignored. If
there are fewer than 14 characters between the D and X, the characters are left-justified and
the rest of the display is blank.

4. To return the alphanumeric display to normal, send DX, perform device clear, or return the
Model 707A to the local state.

5-18

Example PRINT #1, “OUTPUT 18;DMODEL 707AX” !Display MODEL 707A message

IEEE-488 Programming

5.9.6 E — Edit pointer

Purpose To set the edit pointer

Format En

Parameters n=0 Present relay setup

n=1 to 100 Stored relay setup

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument def aults to E0

(present relay setup).

Description With the edit pointer, you can select which setup is affected by subsequent close (C) and open

(N) commands. This can be the present relay setup (zero) or one of the stored setups (1-100).

Programming notes 1. The edit pointer value is independent of the Relay Step and Memory Step values.

2. When using the edit pointer, it is not necessary to use the COPY key, because you are closing/
opening crosspoint relays or setting/clearing stored crosspoints directly and not just turning
on/off crosspoint LEDs.

Example PRINT #1, “OUTPUT 18;E0X” ' Point to relays

PRINT #1, “OUTPUT 18;E50X” ' Point to stored relay setup 50

5.9.7 F — Enable/disable triggers

Purpose To enable/disable triggers.

Format Fn

Parameters n=0 Disable triggers

n=1 Enable triggers

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument def aults to F0

(triggers disabled).

Description With the F command, you control whether the Model 707A responds to a trigger (from the exter-

nal trigger connection or over the IEEE-488 bus). A trigger increments the Relay Step pointer
and copies the setup indicated by the new value from memory to the relays.

Programming notes It is good programming practice to disable triggers before changing the trigger source.

Example PRINT #1, “OUTPUT 18;F0X” ' Enable triggers

•

•

•

PRINT #1, “OUTPUT 18;F1X” ' Disable triggers

5-19

IEEE-488 Programming

5.9.8 G — Data format

Purpose To select the output format of the data sent from the present relay setup or a setup stored in

Format Gn

Parameters n=0 Full output format, all data sent in one talk

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument def aults to G0

Description Overview

memory.

n=1 Full output format, one row of one switching system per talk
n=2 or 3 Inspect output format, all data sent in one talk
n=4 Condensed output format, all data sent in one talk
n=5 Condensed output format, one switching system per talk
n=6 Binary output format, all data sent in one talk
n=7 Binary output format, one switching system per talk

(full output format, all data sent in one talk).

The G command specifies the format of crosspoint data sent by the Model 707A over the IEEE­488 bus in response to the U2 command. Data concerning the setup is sent by a “U2,n” com­mand (either the present relay setup or a stored setup). You can control the data format and quan­tity sent. The full, condensed, and binary formats list the open or closed states of every
crosspoint in the setup; the inspect format shows only closed crosspoints.

G0, G1 = Full output format

With the G0/G1 full output formats, the open or closed states of all crosspoints in a setup are
sent in printable ASCII. An ASCII “-” represents an open crosspoint, and an ASCII “X” repre­sents a closed crosspoint. For G0, all data is sent in one talk; for G1, the data from one row of
one switching system is sent per talk. An example of these formats is shown in Figure 5-10 for
the example setup of Table 5-10.

G2, G3 = Inspect output format

With the G2/G3 inspect output formats, the row/column address of each closed crosspoint in a
setup is sent in printable ASCII. An ASCII letter (A-H) represents a row, and an ASCII string of
up to two numbers (0-60) represents a column. Successive crosspoints are separated with a
comma. All data is sent in one talk. Figure 5-11 sho ws the formats of the example setup in Table
5-10.

G4, G5 = Condensed output format

The G4/G5 condensed output formats specify the states of all crosspoints with eight bits repre­senting the eight crosspoints of a column. A set bit indicates a closed crosspoint. The hexadeci­mal representation of the binary value formed by these eight bits is sent as two printable ASCII
characters. For G4, all data is sent in one talk; for G5, the data from one switching system is sent
per talk. An example of these formats is shown in Figure 5-12 for the example setup of Table
5-10.

G6, G7 = Binary output format

5-20

The G6/G7 binary output formats specify the states of all crosspoints with an 8-bit group of bits
representing the eight crosspoints of a column. A set bit indicates a closed crosspoint. For G6,

IEEE-488 Programming

all data is sent in one talk; for G7, the data from one switching system is sent per talk. These
formats are shown in Figure 5-13 for the example setup of Table 5-10.

Table 5-10

Master/slave setup example

Unit Closed crosspoints

Master
Slave 1
Slave 2
Slave 3
Slave 4

A1, A2, B3, B5, C7, C8, D9, D10, F11, F12
A13, A14, C15, C16, E17, E18
A25, A26, H27, H30, A36
A37, H38, H43, G48
G49, A50, A51, H55, H56, E57, E60

Obtaining data

Generally, data is placed into a string or numeric v ariable. For e xample, a typical input sequence
in BASIC is:

PRINT #1, “ENTER 18"
LINE INPUT #2, CROSSPOINT$

In this example, the complete crosspoint string is placed in the CROSSPOINT$ variable.

5-21

IEEE-488 Programming

Programming notes 1. Table 5-11 lists the number of bytes that are transmitted for the various data formats.

2. Since the data is transmitted in continuous strings (without carriage returns or line feeds), you
must format the data for display or printing legibility.

Table 5-11

Byte counts for data format

Stand-alone Master with four slaves

SETUP 003
A

B

C

D

E
F
G
H
SLAVE 001
A

B

C

D

E
F
G
H

XX

X

Bytes per

Format

G0
G1
G2
G3
G4
G5
G6
G7

Notes:

1. In addition, each unit is identified with a 9-byte ASCII string.

2. This value depends on the number of closed crosspoints.

3. Maximum of five talks, depending on number of slaves in the system.

X

X

X

X

X

talk

641
79 (Note 1)
(Note 2)
(Note 2)
154
154
76
76

X

X

Talks per
setup

1
9
1
1
1
1
1
1

Total
bytes

641
641
(Note 2)
(Note 2)
154
154
76
76

XX

Bytes per
talk

3205
79 (Note 1)
(Note 2)
(Note 2)
770
154
380
76

X

X

Talks per
setup

1
45
1
1
1
5 (Note 3)
1
5 (Note 3)

Total
bytes

3205
3205
(Note 2)
(Note 2)
770
770
380
380

X

X

CARD 1 COLS. CARD 6 COLS.

Notes:

1. Slaves 2-4 have the same format as Slave 1.

2. Carriage returns and line feeds are not sent. They are shown here to improve readability.

3. Spacing between columns is one ASCII space.

Figure 5-10

G0 and G1 full output formats

5-22

A001,A002,B019,B020,C027,C028,D037,D038,F061,F062,A073,A074,C085,C086,E121,E122,A187,A188,
H205,H206,A223,A224,H265,H266,G301,G302,A313,A314,H337,H338,E355,E356

Note: Carriage returns and line feeds are not sent. They are shown here to improve readability.

Figure 5-11

G2 and G3 inspect output formats

IEEE-488 Programming

0003 00
010100000000 000000000000
000000000000 020200000000

MASTER

SLAVE 1

Notes

1. Slaves 2-4 have the same format as that shown.

2. Carriage returns, line feeds, spaces, and blank lines are not sent. They are shown here to improve readability.

3. “XX” represents a 1-byte checksum value (hexadecimal) in printable ASCII.

4. The rows that correspond to the G4/G5 data are as follows:

G4/G5 Corresponding
Data Row

00
01
02
04
08
10
20
40
80

000004040000 000000000000
080800000000 000000000000
000000000000 000000000000
202000000000 000000000000
XX

0003 01
010100000000 000000000000
040400000000 000000000000
000000000000 000000000000
000000000000 000000000000
101000000000 000000000000
000000000000 000000000000
XX

none

A
B
C
D
E
F
G
H

SETUP NUMBER (2 BYTES), UNIT NUMBER (1 BYTE)
CARD 1, COLS. 1-12

CARD 6, COLS. 61-72
CHECKSUM

Figure 5-12

G4 and G5 condensed output formats

5-23

IEEE-488 Programming

00000000
00000001
00000000
00000000
00000010
00000000

MASTER

00000000
00001000
00000000
00000000
00000000
00100000
00000000
XXXXXXXX

00000011
00000001
00000000
00000000
00000010
00000000
00000000
00001000
00000000
00000000
00000000
00100000
00000000

00000000
00000000
00000000
00000000
00000000
00000100
00000000
00000000
00000000
00000000
00000000
00000000
00000000

00000000
00000000
00000000
00000000
00000100
00000000
00000000
00000000
00000000
00000000
00000000
00000000

ROW H ROW A

00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

SETUP NUMBER (2 BYTES),
UNIT NUMBER (1 BYTE)

COLS. 1-6
COLS. 7-12

COLS. 61-66
COLS. 67-72
CHECKSUM

CARD 1

CARD 6

00000000
00000001
00000000
00000100
00000000
00000000

SLAVE 1

Notes

1. Row A corresponds to the least significant bit of each 8-bit group, Row H to the most significant bit.

2. Slaves 2-4 have the same format as that shown.

3. Data is shown as the binary representation of 8-bit binary numbers. The binary value sent may not correspond to a printable
ASCII character.

4. Carriage returns, line feeds, spaces, and blank lines are not sent. They are shown here to improve readability.

5. "XXXXXXXX" represents an 8-bit checksum value in binary.

00000000
00000000
00000000
00010000
00000000
00000000
00000000
XXXXXXXX

00000011
00000001
00000000
00000100
00000000
00000000
00000000
00000000
00000000
00010000
00000000
00000000
00000000

00000001
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000

Figure 5-13

G6 and G7 binary output formats

5-24

5.9.9 H — Hit key

Purpose To allow emulation of front panel key press sequence.

Format Hn

Parameters The parameter “n” represents the number of the front panel key as shown in the following table.

IEEE-488 Programming

Command Key Command Key

H1 MEMORY H22 H
H2 RELAYS H23 F
H3 COPY DISPLAY → MEMORY H24 D
H4 COPY DISPLAY → RELAYS H25 B
H5 AUTOMATIC H26 7
H6 SCROLL ▲ H27 4
H7 SCROLL ▼ H28 1
H8 INSERT H29 0

H9 DELETE H30 8
H10 MENU H31 5
H11 SETTLING TIME H32 2
H12 MAKE/BREAK H33 CANCEL
H13 BREAK/MAKE H34 9
H14 LOCAL H35 6
H15 ENABLE H36 3
H16 SOURCE H37 ENTER
H17 MANUAL H38 RESET
H18 G H39 CLEAR
H19 E H40 OPEN
H20 C H41 CLOSE
H21 A

Description The H command and its options allow you to emulate front panel keystroke sequences. To emu-

late any such sequence, simply send the appropriate commands in the necessary order.

Programming notes 1. The X character must follow each command in a multiple command string.

2. The H command is functional even if LLO (Local Lockout) is in effect.

5-25

IEEE-488 Programming

5.9.10 I — Insert blank setup

Purpose To insert a blank setup in memory.

Format In

Parameters n=1 to 100 Stored relay setup

Description During execution of this command, setups “n” through 99 are shifted up to the next highest loca-

tion in memory (99 to 100, 98 to 99... n to n+1). Then, all crosspoints of setup “n” are cleared.
The front panel display is blanked during an insert operation.

Example PRINT #1, “OUTPUT 18;I50” ' Insert blank setup at location 50

5.9.11 J — Self-test

Purpose To test ROM and RAM.

Format Jn

Parameters n=0 Perform self-test

Description The self-test command starts execution of the ROM and RAM. If an error is detected, a RAM

F AIL or ROM F AIL message is displayed. Also, the self-test f ailed bit is set in the U1 error status
word (paragraph 5.9.22). Any front panel keypress or bus command overrides the message.

Programming notes 1. The value “n”, if sent, must be zero.

2. Allow approximately four seconds for the instrument to complete the self-test.

3. The instrument holds off bus operation with the NRFD line during self-test operation. Thus,
no commands can be sent during the self-test if hold-off on X is enabled.

Example PRINT #1, “OUTPUT 18;J0X” ' Perform self-test

5.9.12 K — EOI and hold-off

Purpose To enable/disable EOI and bus hold-off on X.

Format Kn

Parameters n= 0 Send EOI with last byte, hold-off on X until Ready

n = 1 No EOI, hold-off on X until Ready
n = 2 Send EOI with last byte, do not hold-off on X
n = 3 No EOI, do not hold-off on X
n = 4 Send EOI with last byte, hold-off on X until Matrix Ready
n = 5 No EOI, hold-off on X until Matrix Ready

5-26

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument def aults to K0

(send EOI with last byte, hold-off on X until Ready).

IEEE-488 Programming

Description The EOI line provides one method to positively identify the last byte in the data string sent by

the instrument. When enabled, EOI is asserted with the last byte the instrument sends over the
bus.

Bus hold-off allows the instrument to temporarily hold up b us operation via the NRFD line when
it receives the X character until all commands are processed. The advantage of using bus hold­off is that no commands are missed while the instrument is processing previously recei ved com­mands. Typical hold-off times are discussed in paragraph 5.11.

Programming notes 1. Some controllers rely on EOI to terminate their input sequences. Suppressing EOI may cause

the controller input sequence to hang.

2. When reading a buffer, EOI is asserted only at the end of the entire buffer transmission.

3. When enabled, EOI is asserted with the last byte in the terminator.

4. When bus hold-off is enabled, all bus acti vity is held up for the duration of the hold-off period,
not just for the duration of the communication with the Model 707A.

Example PRINT #1, “OUTPUT 18;K1X” ' No EOI, hold-off on X until Ready

PRINT #1, “OUTPUT 18;K2X” ' Send EOI with last byte, do not hold-off on X

5.9.13 L — Download setups

Purpose To download setups from the controller to the Model 707A.

Format Lbbbb...X

Parameters bbbb... represents the G4/G5 or G6/G7 output string.

Description This command downloads setup information in a G4/G5 or G6/G7 data format. It is used in con-

junction with the U2 command (output setup data) to back up or expand the setups stored in the
Model 707A.

G formats are discussed in paragraph 5.9.8; see paragraph 5.9.22 for U commands.

Programming notes 1. The data format for downloading is specified by the G format presently in effect.

2. The setup data string begins with a setup number and unit number and ends with a checksum
value.

3. The setup number is specified in a U2,n command (output setup “n”), as shown in the follow­ing programming example.

Example DIM SETUP$[32] ' Dimension for stand-alone

PRINT #1, “REMOTE 18"
PRINT #1, “OUTPUT 18;G4U2,1X”
PRINT #1, “ENTER 18" ' Get setup data
LINE INPUT #2, SETUP$
PRINT SETUP$[1,6]
PRINT SETUP$[7,30] ' Print setup data card by card
PRINT SETUP$[31,32] ' Print checksum
PRINT “PRESS ANY KEY TO CONTINUE” ' Inspect setup data
DO
LOOP WHILE INKEY$= “ “
PRINT #1,”OUTPUT 18;”L”+SETUP$ ' Download setup back to 707A
+”X”18;”L”+SETUP$+”X”"

' Setup #1 in G4 format

' Print setup and unit numbers

' Wait for keypress

5-27

IEEE-488 Programming

F

5.9.14 M — SRQ and serial poll byte

Purpose To program which conditions generate an SRQ (service request).

Format Mn

Parameters n=0 SRQ disabled

n=1 Not used
n=2 Not used
n=4 Not used
n=8 Matrix Ready
n=16 Ready for trigger
n=32 Error
n=128 Not used

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument defaults to

M0 (SRQ disabled).

Description The SRQ command selects which conditions cause the Model 707A to generate an SRQ (service

request). Once an SRQ is generated, the serial poll byte can be checked to determine if the
Model 707A was the instrument that generated the SRQ, and, if so, what conditions caused it.

The general format of the SRQ mask used to generate SRQs is shown in Figure 5-14. By sending
the appropriate M command, you can set the appropriate bit(s) to enable SRQ generation if those
particular conditions occur. Possible conditions are:

• A front panel key has been pressed (M2).

• An interrupt condition has been received at the Digital I/O port (M4).

• The Matrix Ready signal has been asserted (M8).

• The Ready (for trigger) signal has been asserted (M16).

• An error has occurred (M32). The nature of the error can be determined by reading the U1
error word as described in paragraph 5.9.22.

Decimal

Weighting

Bit Position

Not Used

S

RQ 84 707A

(Serial Poll Byte Only)

by

Readyfor Trigger

1286432168421

B7 B6 B5 B4 B3 B2

Error

B1 B0

Not Used

Front Panel
Key Press

Digital I/O
Interrupt

Matrix Ready

igure 5-14

SRQ mask and serial poll byte format

5-28

IEEE-488 Programming

Serial poll byte

The general format of the serial poll byte is shown in Figure 5-14. Note that all bits except for
bit 6 correspond to the bits in the SRQ mask. These bits flag the following conditions:

Matrix ready (bit 3) — Set whenever the Matrix Ready signal is asserted. Cleared by the start of
relay switching.

Ready for trigger (bit 4) — Set when the Ready signal is asserted. This bit is cleared by:

• Receipt of X.

• Start of relay switching.

• Front panel keypress on master unit.

• Changing Make/Break or Break/Make row.

• Performing self-test.

• Pressing RELAYS key.

NOTE

Using the H command to “hit” keys could cause the Ready bit to cycle twice:
once when the H command is processed and again when the key press is
processed.

Error (bit 5) — Set if an error condition occurs. Cleared by reading the U1 error status word
(paragraph 5.9.22).

SRQ (bit 6) — Set if the Model 707A requests service via the SRQ line; cleared by a serial poll.

Programming notes 1. The serial poll byte should be read once the instrument has generated an SRQ to clear the SRQ

line.

2. All bits in the serial poll byte latch when the instrument generates an SRQ.

3. If an error occurs, bit 5 (error) in the serial poll byte latches and remains so until the U1 word
is read (paragraph 5.9.22).

4. Multiple error conditions can be programmed by adding up the individual command values.
For example, send M12X for SRQ under matrix ready and digital I/O interrupt conditions.

Example PRINT #1, "CLEAR 18"

PRINT #1, "REMOTE 18"
PRINT #1, "OUTPUT 18;M32X" ' Attempt to program invalid option
PRINT #1, "OUTPUT 18;A2X" ' Check interface status

WAITSRQ:
IF NOT(srq%()) THEN GOTO WAIT SRQ
PRINT #1, "SPOLL 18" ' Serial poll the instrument
INPUT #2, S ' Read serial poll byte
PRINT "B7 B6 B5 B4 B3 B2 B1 B0" ' Label the bit positions
FOR I=7 TO 0 STEP-1 ' Loop eight times
PRINT BIT (S,I); ' Display the bit positions
NEXT I
PRINT
PRINT #1, "OUTPUT 18;U1X"
PRINT #1, "ENTER 18" ' Get U1 status to clear error
LINE INPUT #2, ERROR$
PRINT ERROR$

' Display error status

' Program for SRQ on error

' Wait for SRQ to occur

' Program for error status

5-29

IEEE-488 Programming

5.9.15 N — Open crosspoint

Purpose To open crosspoints in a setup.

Format Nrc(,rc)...(,rc)

Parameters r=A to H Row designation of crosspoint

c=1 to 360 Column designation of crosspoint (360 with maximum of five Model 707A units)

Description The N command opens crosspoints in the setup indicated by the edit pointer. If the edit pointer indi-

cates the present relay setup (zero), the specified crosspoint relays are opened immediately. If the
edit pointer indicates a setup stored in memory (1-100), the specified crosspoints are cleared.

Programming notes 1. Do not include parentheses in command strings. They indicate that the option and associated

comma delimiter are optional.

2. Up to 25 crosspoints per mainframe can be specified in one open command (with a master
and four slaves, the limit is 125 crosspoints). In the same command string, up to 25 cross­points per mainframe can be closed. If either limit is exceeded, an IDDCO results.

3. The maximum value of the column parameter depends on the configuration (72 for stand­alone, 360 for master with four slave units). An IDDCO results if the maximum value is
exceeded.

4. This command is equivalent to multiple light pen operation(s).

Example PRINT #1, "OUTPUT 18;NA55X" ' Open one crosspoint

PRINT #1, "OUTPUT 18;NA55,A56,B49,B50X" ' Open multiple crosspoints

5.9.16 O — Digital output

Purpose To set the states of the digital output lines.

Format Ovvv

Parameters vvv=000 to 255 Decimal value of digital output

Default Upon power-up or after receiving a DCL, SDC, or R0X command, the instrument defaults to

O000 (all digital outputs set to logic low).

Description This command is a decimal representation of the states of individual output lines of the digital

I/O port, where “1” is logic high and “0” is logic low. Bit assignments and corresponding con­nector pins are shown below:

Bit Position 7 6 5 4 3 2 1 0
Bit Weight 128 64 32 16 8 4 2 1
Digital 8 7 6 5 4 3 2 1

Programming notes 1. In a master/slave configuration, only the output of the master unit is updated.

2. Leading zeros are not necessary in the parameter value.

3. This command is equivalent to a multiple light pen operation(s).

4. Output is negative true logic. Setting bit high will make output go low (sink).

5-30

Example PRINT #1, "OUTPUT 18;O15X" ' Set bits <3-0> high

PRINT #1, "OUTPUT 18;O0X" ' Restore default condition