Tektronix DDA-08, DDA-16 Users Guide

DDA-08/16

User’s Guide

A GREATER MEASURE OF CONFIDENCE

WARRANTY

Hardware

Keithley Instruments, Inc. warrants that, for a period of one (1) year from the date of shipment (3 years for Models 2000,
2001, 2002, 2010 and 2700), the Keithley Hardware product will be free from defects in materials or workmanship. This
warranty will be honored provided the defect has not been caused by use of the Keithley Hardware not in accordance with
the instructions for the product. This warranty shall be null and void upon: (1) any modification of Keithley Hardware that
is made by other than Keithley and not approved in writing by Keithley or (2) operation of the Keithley Hardware outside
of the environmental specifications therefore.

Upon receiving notification of a defect in the Keithley Hardware during the warranty period, Keithley will, at its option,
either repair or replace such Keithley Hardware. During the first ninety days of the warranty period, Keithley will, at its
option, supply the necessary on site labor to return the product to the condition prior to the notification of a defect. Failure
to notify Keithley of a defect during the warranty shall relieve Keithley of its obligations and liabilities under this
warranty.

Other Hardware

The portion of the product that is not manufactured by Keithley (Other Hardware) shall not be covered by this warranty,
and Keithley shall have no duty of obligation to enforce any manufacturers' warranties on behalf of the customer. On those
other manufacturers’ products that Keithley purchases for resale, Keithley shall have no duty of obligation to enforce any
manufacturers’ warranties on behalf of the customer.

Software

Keithley warrants that for a period of one (1) year from date of shipment, the Keithley produced portion of the software or
firmware (Keithley Software) will conform in all material respects with the published specifications provided such Keithley
Software is used on the product for which it is intended and otherwise in accordance with the instructions therefore.
Keithley does not warrant that operation of the Keithley Software will be uninterrupted or error-free and/or that the Keithley
Software will be adequate for the customer's intended application and/or use. This warranty shall be null and void upon any
modification of the Keithley Software that is made by other than Keithley and not approved in writing by Keithley.

If Keithley receives notification of a Keithley Software nonconformity that is covered by this warranty during the warranty
period, Keithley will review the conditions described in such notice. Such notice must state the published specification(s)
to which the Keithley Software fails to conform and the manner in which the Keithley Software fails to conform to such
published specification(s) with sufficient specificity to permit Keithley to correct such nonconformity. If Keithley deter­mines that the Keithley Software does not conform with the published specifications, Keithley will, at its option, provide
either the programming services necessary to correct such nonconformity or develop a program change to bypass such
nonconformity in the Keithley Software. Failure to notify Keithley of a nonconformity during the warranty shall relieve
Keithley of its obligations and liabilities under this warranty.

Other Software

OEM software that is not produced by Keithley (Other Software) shall not be covered by this warranty, and Keithley shall
have no duty or obligation to enforce any OEM's warranties on behalf of the customer.

Other Items

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

Items not Covered under Warranty

This warranty does not apply to fuses, non-rechargeable batteries, damage from battery leakage, or problems arising from
normal wear or failure to follow instructions.

Limitation of Warranty

This warranty does not apply to defects resulting from product modification made by Purchaser without Keithley's express
written consent, or by misuse of any product or part.

Disclaimer of Warranties

EXCEPT FOR THE EXPRESS WARRANTIES ABOVE KEITHLEY DISCLAIMS ALL OTHER WARRANTIES,
EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION, ALL IMPLIED WARRANTIES OF MERCHANT­ABILITY AND FITNESS FOR A PARTICULAR PURPOSE. KEITHLEY DISCLAIMS ALL WARRANTIES WITH
RESPECT TO THE OTHER HARDWARE AND OTHER SOFTWARE.

Limitation of Liability

KEITHLEY INSTRUMENTS SHALL IN NO EVENT, REGARDLESS OF CAUSE, ASSUME RESPONSIBILITY FOR
OR BE LIABLE FOR: (1) ECONOMICAL, INCIDENTAL, CONSEQUENTIAL, INDIRECT, SPECIAL, PUNITIVE OR
EXEMPLARY DAMAGES, WHETHER CLAIMED UNDER CONTRACT, TORT OR ANY OTHER LEGAL THEORY,
(2) LOSS OF OR DAMAGE TO THE CUSTOMER'S DATA OR PROGRAMMING, OR (3) PENALTIES OR PENALTY
CLAUSES OF ANY DESCRIPTION OR INDEMNIFICATION OF THE CUSTOMER OR OTHERS FOR COSTS, DAM­AGES, OR EXPENSES RELATED TO THE GOODS OR SERVICES PROVIDED UNDER THIS WARRANTY.

Keithley Instruments, Inc.

Sales Offices: BELGIUM: Bergensesteenweg 709 • B-1600 Sint-Pieters-Leeuw • 02-363 00 40 • Fax: [phone]

CHINA: Yuan Chen Xin Building, Room 705 • 12 Yumin Road, Dewai, Madian • Beijing 100029 • 8610-6202-2886 • Fax: [phone]
FINLAND: Tietäjäntie 2 • 02130 Espoo • Phone: [phone] • Fax: [phone]
FRANCE: 3, allée des Garays • 91127 Palaiseau Cédex • 01-64 53 20 20 • Fax: [phone]
GERMANY: Landsberger Strasse 65 • 82110 Germering • 089/84 93 07-40 • Fax: [phone]
GREAT BRITAIN: Unit 2 Commerce Park, Brunel Road • Theale • Berkshire RG7 4AB • 0118 929 7500 • Fax: [phone]
INDIA: Flat 2B, Willocrissa • 14, Rest House Crescent • Bangalore 560 001 • 91-80-509-1320/21 • Fax: [phone]
ITALY: Viale San Gimignano, 38 • 20146 Milano • 02-48 39 16 01 • Fax: [phone]
JAPAN: New Pier Takeshiba North Tower 13F • 11-1, Kaigan 1-chome • Minato-ku, Tokyo 105-0022 • 81-3-5733-7555 • Fax: [phone]
KOREA: 2FL., URI Building • 2-14 Yangjae-Dong • Seocho-Gu, Seoul 137-888 • 82-2-574-7778 • Fax: [phone]
NETHERLANDS: Postbus 559 • 4200 AN Gorinchem • 0183-635333 • Fax: [phone]
SWEDEN: c/o Regus Business Centre • Frosundaviks Allé 15, 4tr • 169 70 Solna • 08-509 04 679 • Fax: [phone]
SWITZERLAND: Kriesbachstrasse 4 • 8600 Dübendorf • 01-821 94 44 • Fax: [phone]
TAIWAN: 1FL., 85 Po Ai Street • Hsinchu, Taiwan, R.O.C. • 886-3-572-9077• Fax: [phone]

28775 Aurora Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: [phone]

1-888-KEITHLEY (534-8453) • www.keithley.com

4/02

DDA-08/16

User’s Guide

Revision B - March 1999

Part Number: 78340

S

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 and follow all installation, operation, and maintenance information
carefully before using the product. Refer to the manual for complete product specifications.

If the product is used in a manner not specified, the protection provided by the product may be impaired.
The types of product users are:

Responsible body

the equipment is operated within its specifications and operating limits, and for ensuring that operators are adequately
trained.

Operators

of the instrument. They must be protected from electric shock and contact with hazardous live circuits.

Maintenance personnel

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.
Keithley products are designed for use with electrical signals that are rated Installation Category I and Installation

Category II, as described in the International Electrotechnical Commission (IEC) Standard IEC 60664. Most mea­surement, control, and data I/O signals are Installation Category I and must not be directly connected to mains voltage
or to voltage sources with high transient over-voltages. Installation Category II connections require protection for high
transient over-voltages often associated with local AC mains connections. Assume all measurement, control, and data
I/O connections are for connection to Category I sources unless otherwise marked or described in the Manual.

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.

age is present in any unknown circuit before measuring.

Operators of this product must be protected from electric shock at all times. The responsible body must ensure that
operators are prevented access and/or insulated from every connection point. In some cases, connections must be ex­posed to potential human contact. Product operators 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,

may be exposed.

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.

is the individual or group responsible for the use and maintenance of equipment, for ensuring that

use the product for its intended function. They must be trained in electrical safety procedures and proper use

perform routine procedures on the product to keep it operating properly, for example, setting

afety Precautions

A good safety practice is to expect that hazardous volt-

no conductive part of the circuit

5/02

When installing equipment where access to the main power cord is restricted, such as rack mounting, a separate main
input power disconnect device must be provided, in close proximity to the equipment and within easy reach of the
operator.

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.

The instrument and accessories must be used in accordance with its specifications and operating instructions or the
safety of the equipment may be impaired.

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 con-

nections.
If you are using a test fixture, keep the lid closed while power is applied to the device under test. Safe operation re-

quires the use of a lid interlock.

If or 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

associated information very carefully before performing the indicated procedure.
The

CAUTION

the warranty.
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 an 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. Products that consist
of a circuit board with no case or chassis (e.g., data acquisition board for installation into a computer) should never
require cleaning if handled according to instructions. If the board becomes contaminated and operation is affected,
the board should be returned to the factory for proper cleaning/servicing.

heading in a manual explains dangers that might result in personal injury or death. Always read the

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

The information contained in this manual is believed to be accurate and reliable. However, the
manufacturer assumes no responsibility for its use; nor for any infringements of patents or other rights
of third parties that may result from its use. No license is granted by implication or otherwise under any
patent rights of the manufacturer.

THE MANUFACTURER SHALL NOT BE LIABLE FOR ANY SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMA GES RELATED TO THE USE OF THIS PR ODUCT. THIS PRODUCT IS
NOT DESIGNED WITH COMPONENTS OF A LEVEL OF RELIABILITY THAT IS SUITED FOR
USE IN LIFE SUPPORT OR CRITICAL APPLICATIONS.

DriverLINX, SSTNET, and LabOBJX are registered trademarks and DriverLINX/VB is a trademark of
Scientific Software Tools, Inc.

Microsoft and Windows are registered trademarks and Visual C++ and Visual Basic are trademarks of
Microsoft Corporation.

Borland is a registered trademark and Borland C++, Delphi, and Turbo Pascal are trademarks of
Borland International, Inc.

IBM is a registered trademark of International Business Machines Corporation.

Acrobat is a registered trademark of Adobe Systems Incorporated.

All other brand and product names are trademarks or registered trademarks of their respective
companies.

© Copyright Keithley Instruments, Inc., 1999, 1994.

All rights reserved. Reproduction or adaptation of any part of this documentation beyond that permitted
by Section 117 of the 1979 United States Copyright Act without permission of the Copyright owner is
unlawful.

Keithley Instruments, Inc.

28775 Aurora Road, Cleveland, OH 44139

Telephone: [phone] • FAX: [phone]

http://www.keithley.com

Table of Contents

Preface

1

Overview

Supporting Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Functional Description

2

Analog Output Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Output Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

Pacer Clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

Output Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Time Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Pulse Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Hardware Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

Hardware Gate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13

Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15

3

Setup and Installation

Unpacking the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Installing the Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Installing and Configuring DriverLINX

for DDA-08/16 Boards . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Installing the DDA-08/16 Standard Software Package . . . . 3-4

Before Installing DriverLINX . . . . . . . . . . . . . . . . . . . . . 3-4

Selecting the DriverLINX Components to Install . . . . . . 3-4

Installing DriverLINX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

Configuration with DriverLINX . . . . . . . . . . . . . . . . . . . . . . 3-6

Configuring the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Setting Switches on the Board . . . . . . . . . . . . . . . . . . . . . . . 3-8

Setting the Base Address . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Setting the Analog Output Range . . . . . . . . . . . . . . . . . 3-12

Setting the Output Signal . . . . . . . . . . . . . . . . . . . . . 3-14

Setting the Output Range Type . . . . . . . . . . . . . . . . 3-15

Setting the Output Span . . . . . . . . . . . . . . . . . . . . . . 3-17

Installing the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18

Configuring DriverLINX . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19

iii

Cabling and Wiring

4

Attaching Accessory Boards . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

Attaching an STC-37 Screw Terminal Connector . . . . . . . . 4-3

Attaching an STA-U Screw Terminal Accessory . . . . . . . . . 4-4

Attaching an STP-37 Screw Terminal Panel . . . . . . . . . . . . 4-5

Connecting Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

5

Subsystems and Analog I/O

Digital Input Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Digital Input Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Digital Input Timing Events . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Counter/Timer Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Analog Output Subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Analog I/O Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3

Test Panel Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5

6

DriverLINX Calibration and Test Utilities

Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2

Potentiometers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3

Converting Voltage to Raw Counts . . . . . . . . . . . . . . . . . . . 6-7

Converting Current to Raw Counts . . . . . . . . . . . . . . . . . . . 6-7

7

Troubleshooting

Problem Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

Using the DriverLINX Event Viewer . . . . . . . . . . . . . . . . . . 7-1

Device initialization error messages . . . . . . . . . . . . . . . . . . 7-2

Identifying Symptoms and Possible Causes . . . . . . . . . . . . . . . 7-3

Testing Board and Host Computer . . . . . . . . . . . . . . . . . . . . . . 7-5

Testing Accessory Slot and I/O Connections . . . . . . . . . . . . . . 7-6

Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6

A

Specifications

B

Connector Pin Assignments

iv

List of Illustrations

Figure 2-1. DDA-08/16 Functional Block Diagram . . . . . . . 2-2

Figure 2-2. Using a Pacer Clock . . . . . . . . . . . . . . . . . . . . . . 2-7

Figure 2-3. Generating an Output Clock Pulse . . . . . . . . . . 2-10

Figure 2-4. Using a Hardware Trigger . . . . . . . . . . . . . . . . 2-12

Figure 2-5. Using a Hardware Gate . . . . . . . . . . . . . . . . . . . 2-14

Figure 3-1. DDA-16 Board . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Figure 3-2. Setting the Base Address . . . . . . . . . . . . . . . . . 3-11

Figure 3-3. Setting the Output Signal . . . . . . . . . . . . . . . . . 3-15

Figure 3-4. Setting the Output Range Type . . . . . . . . . . . . . 3-16

Figure 3-5. Setting the Output Span . . . . . . . . . . . . . . . . . . 3-18

Figure 4-1. Main I/O Connector on a DDA-16 Board . . . . . 4-2

Figure 4-2. Attaching an STC-37 Screw Terminal Connector 4-3
Figure 4-3. Attaching an STA-U Screw Terminal Accessory 4-4
Figure 4-4. Attaching an STP-37 Screw Terminal Panel . . . 4-5

Figure 4-5. Voltage Output . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6

Figure 4-6. Current Output . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Figure 6-1. Potentiometers (DDA-16) . . . . . . . . . . . . . . . . . . 6-3

Figure B-1. Main I/O Connector (DDA-16) . . . . . . . . . . . . . B-2

List of Tables

Table 2-1. Voltage Output Ranges . . . . . . . . . . . . . . . . . . . . 2-4

Table 3-1. Configuring DDA-08/16 Boards . . . . . . . . . . . . 3-7

Table 3-2. Base Address Switches . . . . . . . . . . . . . . . . . . . 3-11

Table 3-3. Summary of Analog Output Range Switches . . 3-13

Table 3-4. Output Signal Switches . . . . . . . . . . . . . . . . . . . 3-14

Table 3-5. Output Range Type Switches . . . . . . . . . . . . . . 3-16

Table 3-6. Output Span Switches . . . . . . . . . . . . . . . . . . . . 3-17

Table 6-1. Potentiometers . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

Table 7-1. Troubleshooting Information . . . . . . . . . . . . . . . 7-3

Table A-1. DDA-08/16 Specifications . . . . . . . . . . . . . . . . . A-1

Table B-1. Main I/O Connector Pin Assignments for the

DDA-16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3

v

Preface

The

DDA-08/16 User’s Guide

install, and use DDA-08 and DDA-16 boards.

The manual is intended for data acquisition system designers, engineers,
technicians, scientists, and other users responsible for setting up, cabling,
and wiring signals to DDA-08 and DDA-16 boards. It is assumed that
users are familiar with data acquisition principles and with their particular
application.

The

DDA-08/16 User’s Guide

●

Section 1 provides an overview of the features of DDA-08 and
DDA-16 boards, including a description of supporting software and
accessories.

●

Section 2 provides a detailed description of the features of DDA-08
and DDA-16 boards.

●

Section 3 describes how to unpack, configure, and install DDA-08
and DDA-16 boards.

provides the information needed to set up,

is organized as follows:

Section 4 describes how to attach accessory boards and how to wire

●

signals to DDA-08 and DDA-16 boards.
Section 5 describes how to use the Control Panel to test the functions

●

of DDA-08 and DDA-16 boards under Windows
Section 6 describes how to calibrate and test the functions of DD A-08

●



.

and DDA-16 boards under DOS.
Section 7 provides troubleshooting information.

●

Appendix A lists the specifications for DDA-08 and DDA-16 boards.

●

Appendix B lists the connector pin assignments.

●

An index completes this manual.

Throughout the manual, references to DDA-08/16 boards apply to both
DDA-08 and DDA-16 boards. When a feature applies to a particular
board, that board’s name is used.

1

Overview

DDA-08 and DDA-16 boards are analog output boards. The DDA-08/16
board with DriverLINX software requires:

An IBM PC or compatible AT (386 or Pentium CPU) with minimum

●

of 16 MB of memory.
At least one floppy disk drive and one fixed disk drive.

●

MS-DOS/PCDOS 3.1 or high.

●

●

Microsoft Windows 3.x, Windows 95/98, or Windows NT 4.0 or
higher.

●

A compiler supporting Microsoft Windows development.
A mouse is highly recommended.

●

The major features of DDA-08/16 boards are as follows:

Two 4-channel digital-to-analog converters (quad DACs) on the

●

DDA-08 provide eight analog output channels; four quad DACs on
the DDA-16 provide 16 analog output channels.

Multiple analog output channels can be included in an update group

●

and updated simultaneously.
A switch-selectable output signal (voltage output or current output) is

●

supported for each quad DAC.
Five unipolar and bipolar , switch-selectable v oltage output ranges are

●

supported; a current output range of 4 to 20 mA is supported.
All onboard switches can be read by software.

●

An onboard internal pacer clock is provided; you select the update

●

rate through software.

●

An external pacer clock is supported.

1-1

An onboard output clock is provided; you can use the output clock to

●

synchronize other devices to the pacer clock.

●

An external digital trigger is supported.

●

An external gate is supported.

●

An interrupt can be generated when analog output channels are
updated.

Supporting Software

The following software is available for operating DDA-08/16 boards:

●

DDA-08/16 standard software package

DDA-08/16 boards. Includes DriverLINX for Microsoft Windows
and function libraries for writing application programs under
Windows in a high-level language such as Microsoft Visual Basic,
Microsoft Visual C++, Delphi, utility programs, and
language-specific example programs.

— Shipped with

DriverLINX

●

— The high-performance real-time data-acquisition

device drivers for Windows application development including:

●

DriverLINX API DLLs

and drivers supporting the DDA-08/16

hardware.

Analog I/O Panel

●

— a DriverLINX program that verifies the
installation and configuration of DriverLINX to your DD A-08/16
board and demonstrates several virtual bench-top instruments.

Learn DriverLINX

●

— an interactive learning and demonstration
program for DriverLINX that includes a Digital Storage
Oscilloscope.

Source Code

●

●

DriverLINX Application Programming Interface Files

— for the sample programs.

DDA-08/16 compiler.

●

DriverLINX On-line Help System

— provides immediate help as

you operate DriverLINX.

●

Supplemental Documentation

— on DriverLINX installation and
configuration; analog and digital I/O programming; counter/timer
programming; technical reference; and information specific to the
DDA-08/16 hardware.

— for the

1-2 Overview

DDA-08/16 Utilities

●

— The following utilities are provided as part of

the DDA-08/16 standard software package:

●

Calibrate and Test Utility — allows you to select a device to test
and calibrate.

DriverLINX Test Panel — allows you to perform a limited

●

number of tests.

Accessories

Note:

mode

The DDA-08/16 board is calibrated at the factory for

. If the board is to be used in

current mode

, it needs to be

voltage

recalibrated.

The following accessories are available for use with DDA-08/16 boards:

STC-37 screw terminal connector

●

that allow you to access the functions of the board; connects directly
to the DDA-08/16 board without a cable.

●

STA-U screw terminal accessory

that allow you to access the functions of the board; provides a
breadboard area with power and additional screw terminals to access
the user-designed circuitry.

●

STP-37 screw terminal panel

allow you to access the functions of the board; av ailable with a plastic
case (STP-37/C) that you can mount in a standard DIN rail.

●

C-1800 cable

— Unshielded, 18-inch cable with a 37-pin connector
on each end; allows you to connect a DDA-08/16 board to an STA-U
or STP-37. (Note that the C-1800 cable is also available in longer
lengths, if required.)

— Provides 37 screw terminals

— Provides 37 screw terminals

— Provides 37 screw terminals that

S-1800 cable

●

— Shielded, 18-inch cable with a 37-pin connector on
each end; allows you to connect a DDA-08/16 board to an STA-U or
STP-37. (Note that the S-1800 cable is also available in longer
lengths, if required.)

Refer to Keithley’s Products catalog or contact your local sales office for
information on obtaining these accessories.

1-3

2

Functional Description

This section describes the analog output features of DDA-08/16 boards. A
functional block diagram of a DDA-08/16 board is shown in Figure 2-1.
Note that quad DAC2 and quad DAC3 are available on DDA-16 boards
only.

2-1

Quad

DAC0
Data
Buffers

0

1

2

3

PC Bus

Address
Decoder

Interrupt
Generator

Field-Programmable

Gate Array

(FPGA)

Quad
DAC1

4

5

6
7

Quad

DAC2

8

9

10

11

Quad
DAC3

12

13

14
15

Input
Buffers

GATE IN

TRIGGER IN

CLOCK IN

CLOCK OUT

Figure 2-1. DDA-08/16 Functional Block Diagram

2-2 Functional Description

Analog Output Channels

DDA-08 boards contain two quad DACs (quad DAC0 and quad DAC1),
which provide eight analog output channels. DDA-16 boards contain four
quad DACs (quad DAC0, quad DAC1, quad DAC2, and quad DAC3),
which provide 16 analog output channels. Quad DAC0 contains channels
0 through 3; quad DAC1 contains channels 4 through 7; quad DAC2
contains channels 8 through 11; quad DA C3 contains channels 12 through

15.

Each analog output channel contains an input buffer for storing data.
Through software, the host computer loads a single value into the input
buffer of a single channel or loads multiple v alues into the input buf fers of
a sequence of consecutive channels. The analog output values are held in
the input buffers until the channels are updated. At that point, the values
currently held in the input buffers are written to the channels, updating
their output values.

You can update a single analog output channel immediately when the
input buffer is loaded, or you can update several analog output channels
simultaneously using a pacer clock. Refer to page 2-6 for more
information about pacer clocks.

If you want to update several analog output channels simultaneously, you
use software to include one or more quad DACs in the update group. All
channels on the quad DACs in the update group are updated
simultaneously at each pulse of the pacer clock.

Note:

In multi-channel mode, the DDA-08/16 writes all data to a

consecutive range of analog channels.

●

If the Start Channel is greater than the Stop Channel, the channel
sequence is [Start Channel, ..., Last Channel, 0, ..., Stop Channel],
where Last Channel is the highest numbered channel for the
DDA-08/16 model the application is using.

●

The DDA-08/16 can optionally output to all DACs in the range
simultaneously, or write to one DAC in the range at each timing
event.

2-3

In multi-channel list mode, the DDA-08/16 writes all data to a random list
of analog channels.

●

The channel-gain list may contain channels in any order but only with
unity gain. In simultaneous mode, the list may

not

repeat the same

channel.

●

The DDA-08/16 can optionally output to all DACs in the list
simultaneously, or write to one DAC in the list at each timing event.

Refer to the
manual that accompanies your DriverLINX software.

Output Ranges

DDA-08/16 boards support both voltage output and current output. You
select the output signal for each quad DAC using the output signal
switches on the board. Refer to page 3-14 for more information.

Voltage output and current output ranges are described as follows:

●

Using DriverLINX with Your Hardwar e , Keithley DDA-08/16

Voltage output

— For voltage output, you can select one of five
ranges (0 to 10V, 0 to 5V, ±10V, ±5V, or ±2.5V) for each quad DAC.
You select the voltage output range using two switches on the board.
The output span switch determines the span (5V, 10V, or 20V); the
output range type switch determines the output range type (unipolar
or bipolar). Refer to page 3-15 and page 3-17 for more information.

Table 2-1 shows the voltage output ranges provided by each span and
output range type.

Table 2-1. Voltage Output Ranges

Output Range Type

Span

5V 0 to 5V ±2.5V
10V 0 to 10V ±5V
20V

1

Do not select a 20V span with a unipolar output range

type. If you do, the output will saturate at about 10V with
approximately a half scale input to the quad DAC.

2-4 Functional Description

Unipolar Bipolar

Not applicable

1

±10V

Notes:

All channels on a quad DAC have the same voltage output
range; you cannot select a voltage output range on a
channel-by-channel basis.

Make sure that you select a voltage output range that includes all the
output values required by the device connected to your board. In
addition, make sure that the range does not exceed the required values
excessively; this ensures the best possible resolution and prevents
potential damage to the device.

Current output

●

— For current output, the range is always 4 to 20
mA. For current output, you must set the output range type and the
output span switches on the board to current output. Refer to page
3-15 and page 3-17 for more information.

Each analog output channel has a resolution of 12 bits, which translates to
a raw count value between 0 and 4095. For bipolar voltage output ranges,
a value of 0 represents negative full scale and a value of 4095 represents
positive full scale. For unipolar voltage output ranges, a value of 0
represents 0V and a value of 4095 represents positive full scale. For
current output ranges, a value of 0 represents 4mA and a value of 4095
represents 20mA.

Note:

To ensure that the analog output channels power-up to a known
state, the output value from all channels configured for voltage output is
nominally 0V at power-up and the output value from all channels
configured for current output is nominally 0mA at power-up.

2-5

Clocks

Pacer Clocks

DDA-08/16 boards support two types of clocks: a pacer clock and an
output clock. These clocks are described in the following sections.

The pacer clock determines the update rate (the time between each update
of all the channels on the quad DACs in the update group). DDA-08/16
boards provide the following software-selectable pacer clocks:

Hardware internal pacer clock

●

onboard time base. The internal pacer clock determines the update
rate by multiplying a prescaler value (1
100ms, or 1s) by an 8-bit counter value. The prescaler values provide
a wide range of update rates; the 8-bit counter value provides the
resolution that allows you to achieve the exact update rate you
require.

The time between updates can range from 1µs to 4.267 minutes.
For example, assume that you want to update the channels every

50ms. The prescaler value can be 1ms and the counter value can
be 50, or the prescaler value can be 10ms and the counter value can
be 5.

Notes:

determine the length of the output clock pulse and the time delay between
the update of the analog output channels on the quad DACs in the update
group and the output clock pulse. Refer to page 2-8 for more information
about the output clock.

DriverLINX allo ws you to specify the Logical Channel (0 = Pacer Clock,
1 = Output Clock), Clock Source, Clock Tic Period, Mode, and Gate.
Refer to the
manual that accompanies your DriverLINX software.

The prescaler value used by the pacer clock is also used to

Using DriverLINX with Your Hardwar e , Keithley DDA-08/16

— The internal pacer clock uses an

µ

s, 10µs, 100µs, 1ms, 10ms,

When the pacer clock counter is loaded, the channels on the quad
DACs in the update group are updated and the pacer clock counter
starts counting down. (Note that a slight time delay occurs between

2-6 Functional Description

the time the pacer clock counter is loaded and the time the channels
are updated.) When the pacer clock counter counts down to zero, all
the channels on the quad DA Cs in the update group are updated again
and the process repeats.

●

Hardware external pacer clock

— An e xternal pacer clock is useful
if you want to update the channels at rates not available with the
internal clock, if you want to update the channels at uneven intervals,
or if you want to update the channels based on an external event.

The external pacer clock is an externally applied TTL-compatible
signal, which you attach to the CLOCK IN pin (pin 1) of the main I/O
connector. At each active edge of the external pacer clock, the
channels are updated. The active edge is software-selectable; at
power-up, the board assumes that the acti ve edge for an external pacer
clock is a falling edge.

Figure 2-2 illustrates how analog output channels are updated when using
an internal pacer clock and when using an external pacer clock with a
falling edge as the active edge. (Note that Figure 2-2 assumes that you are
not using a hardware trigger; refer to Figure 2-4 on page 2-12 when using
a hardware trigger.)

Operation is started

External Pacer
Clock

Internal Clock
Source

(idle state)

count

Updates begin when
using an internal
pacer clock

count

Figure 2-2. Using a Pacer Clock

Updates begin when
using an external
pacer clock

count

count

2-7

Output Clock

Notes:

(internal or external), make sure that you do not update the analog output
channels faster than the host computer writes to the input buffers of the
channels. Typical update rates range from 1kHz to 20kHz; the actual rate
depends on a number of factors, including your computer, the operating
system/environment, and software issues. Also keep in mind the settling
time of the channels on the DDA-08/16 board; refer to Appendix A for
information.

At power-up, the pacer clock is disabled.

If enabled, the output clock generates an output pulse for each update of
the analog output channels on the quad DACs in the update group (using
either the internal pacer clock or the external pacer clock). You can use
this output pulse to synchronize other devices to the pacer clock.

The output pulse is issued from the CLOCK OUT pin (pin 20) of the
main I/O connector. The polarity of the output pulse (falling edge or
rising edge) is software-selectable. If you select a falling-edge pulse, the
output from CLOCK OUT starts high; if you select a rising-edge pulse,
the output from CLOCK OUT starts low. On power-up, the board
assumes that you want to generate a falling-edge pulse.

When determining the update rate for a hardware pacer clock

Time Delay

Through software, you can specify a time delay between the update of the
analog output channels on the quad DACs in the update group and the
output clock pulse. The output clock determines the time delay by
multiplying the prescaler value used by the internal pacer clock by the
output clock’s own independent 8-bit counter value. The output clock
counter is reloaded each time the analog output channels are updated.

For example, if the prescaler value is 1ms and you want a 30ms time
delay between the update of the analog output channels and the output
clock pulse, the output clock counter value must be 30.

2-8 Functional Description

Notes:

If the output clock counter value is 0, the output clock pulse is
generated simultaneously with the update of the analog output channels
(no delay).

The DDA-08/16 can write analog output samples

after

the hardware
detects a digital trigger condition. Use post-triggering in DriverLINX
when you want to synchronize the start of data acquisition with an
external signal. Digital Start Events contain

mask, pattern,

and

match

fields. The mask is logically ANDed with the digital input data on the
Logical Channel and then compared with the

pattern

for a

match/mismatch.

●

Specify the

●

Specify the

Channel
Mask

and

as 0.

Pattern

properties as 1 to specify the bit

position of the 1-bit trigger input.

●

Specify the

Match

property as

Not equals

to trigger on the edge of

the trigger input.

●

Specify the

Delay

property as any number of samples from

0 to 232 - 1.
Connect the signal to the TRIGGER IN line.

●

Refer to

Using DriverLINX with Your Hardware, Keithley DDA-08/16

manual that accompanies your DriverLINX software.

2-9

Pulse Length

The period of the output pulse is equal to the prescaler value. Since the
prescaler generates a square wave, the length of the output pulse is equal
to half of the prescaler value. For example, if the prescaler v alue is 10 ms,
the length of the output pulse is 5ms.

Figure 2-3 illustrates a falling-edge output pulse that is 5ms in length
(prescaler value is 10ms) and is generated 30ms after the analog output
channels on the quad DACs in the update group are updated. Since there
is only one prescaler, the prescaler v alue must be 10ms for both the pacer
clock and the output clock.

Pacer Clock
Prescaler = 10ms
Counter value = 5

Output Clock

Falling-edge pulse

50ms

50ms

Pacer clock
counter loaded

First update of
the channels

First output
clock pulse

20
ms

30ms

time

delay

50ms

45ms

5ms output pulse

Figure 2-3. Generating an Output Clock Pulse

2-10 Functional Description

In DriverLINX, Timing Events specify how the hardware paces or clocks
the sample output. DriverLINX uses the Timing Event to program when
the DDA-08/16 writes the next analog output sample to the DACs.

The DDA-08/16 supports the following Timing Events:

●

●

●

Hardware Trigger

You can enable a hardware trigger through software. A hardware trigger is
an externally applied, edge-sensitive, digital signal that determines when
the analog output channels on the quad DACs in the update group can
respond to either an internal or an external pacer clock.

You connect the digital trigger signal to the TRIGGER IN pin (pin 2) of
the main I/O connector. If the trigger is enabled, the board waits for an
active edge on TRIGGER IN. The active edge is software-selectable; at
power-up, the board assumes that the acti v e edge for a hardware trigger is
a falling edge.

None —

Output requires no

pacing

as DriverLINX is writing only a

single value.

Rate —

The DDA-08/16 supports only fixed rate analog output using
internal and external clocks. The Rate Generator provides a fix ed rate
clock with equal time intervals between tics. An internally clocked
Rate Generator produces a fixed rate clock with equal time intervals
between tics. An externally clocked Rate Generator produces a rate
clock with unknown time intervals between tics.

Digital —

DriverLINX uses an external digital input signal to pace

the output to each sample.

When the board detects an active edge, the channels respond to each pulse
of the pacer clock until the trigger circuitry is disabled.

The actual point at which the channels are updated depends on whether
you are using an internal pacer clock or an external pacer clock. These
considerations are described as follows:

●

Internal pacer clock —

The internal pacer clock remains idle until
the trigger event occurs. When the trigger event occurs, the pacer
clock counter is loaded and the channels are updated. (Note that a
slight time delay occurs between the time the pacer clock counter is
loaded and the time the channels are updated.)

2-11

●

Figure 2-4 illustrates how the channels are updated when using a
rising-edge hardware trigger.

Hardware Trigger

(Rising Edge)

External Pacer Clock

(Falling Edge)

External pacer clock —

When the trigger event occurs, the board
begins monitoring the state of the external pacer clock signal. At the
next active edge of the external pacer clock, the channels are updated.

Trigger event occurs

Updates begin when
using an external
pacer clock

Internal Clock
Source

(idle state)

count

Updates begin when
using an internal
pacer clock

count

count

count

Figure 2-4. Using a Hardware Trigger

Note:

The time at which the analog output channels are updated also

depends on the pacer clock. Refer to page 2-6 for more information.

2-12 Functional Description

Hardware Gate

You can enable a hardware gate through software. A hardware gate is an
externally applied, level-sensitive, digital signal that determines when the
analog output channels on the quad DACs in the update group are
updated.

You connect the gate signal to the GATE IN pin (pin 21) of the main I/O
connector. If the hardw are gate is enabled, the software-selectable state of
the gate signal determines whether the channels are updated, as follows:

●

●

When using the hardware gate, the way the channels are updated depends
on whether you are using an internal pacer clock or an external pacer
clock. These considerations are described as follows:

If you specify a positive gate, the channels are updated only if the
signal to GATE IN is high; if the signal goes low, the channels are no
longer updated.

If you specify a negative gate, the channels are updated only if the
signal to GATE IN is low; if the signal goes high, the channels are no
longer updated.

Internal pacer clock —

●

The internal pacer clock stops counting
down when the gate signal goes inactive. When the gate signal goes
active again, the internal pacer clock resumes counting where it left
off.

External pacer clock —

●

The signal from the external pacer clock
continues uninterrupted while the gate signal is inactive; updates are
always synchronized to the external pacer clock.

Figure 2-5 illustrates a positive hardware gate with both an e xternal pacer
clock and an internal pacer clock. The polarity of the external pacer clock
is falling edge.

2-13