Tektronix EXP-16,EXP-16/A Users Guide

EXP-16 and EXP-16/A

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.

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NETHERLANDS: Postbus 559 • 4200 AN Gorinchem • 0183-635333 • Fax: [phone]
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1-888-KEITHLEY (534-8453) • www.keithley.com

4/02

EXP-16

and

EXP-IG/A

User’s

Revision

Part

E

-

Number:

Guide

April

1995

61

590

New Contact Information

Keithley Instruments, Inc.

28775 Aurora Road

Cleveland, OH 44139

Technical Support: 1-888-KEITHLEY

Monday – Friday 8:00 a.m. to 5:00 p.m (EST)

Fax: [phone]

Visit our website at http://www.keithley.com

The information contained
Instruments,

of

third parties that

patent

rights

Inc.,

of

Keithley

assumes

may

result

Instruments, hc.

in

this

manual

no

responsibility for its

from

is believed

its use.

to

be accixate and reliable. However, Keithley

use

or

No

license is granted

for

any

infringements

by

implication

of

patents

or

or

other

otherwise under any

rights

KEITHLEY INSTRUMENTS,

OR

CONSEQUENTIAL

PRODUCT
SUITABLE

Refer

All

brand

0

Copyright Keithley Instruments, Inc., 1985,1992, 1995.

All

rights reserved. Reproduction

by

Section 117

unlaw

to

fd

IS

NOT

DESIGNED

FOR

USE

IN LIFE SUPPORT OR

your

Keithley Instruments license agreement

and

product names

of

the 1976 United States

.

INC.,

DAMAGES

WITH

are

trademarks

or

adaptation

SHALL

RELATED

NOT

COMPONENTS

CRITICAL

or

registered trademarks

of

Copyright

BE LIABLE

TO

any part

Act without permission

THE

USE

OF

A

APPLICATIONS.

for

specific

of

this

FOR

ANY

SPECIAL,

OF

THIS

PRODUCT.

LEVEL

documentation beyond that permitted

OF

RELIABILITY

warranty

and liability information.

of

their respective companies.

of

the Copyright owner

WCIDENTAL,

THIS

is

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

Preface

1

Overview

Features
Applications
Accessories

2

Functional Description

Input

Multiplexer

Insfnunentation Amplifier.
CJC Circuit
Power

............................................

.........................................

.........................................

Circuits
Open-Thermocouple Detection
Signal Filtering
Current-Measuring Resistor

..........................................

..........................................

..............................................

Table

of

Contents

........................................

........................

....................................

..........................

.............................

1-1

i-2

1-2

2.2

2.2

2.3

2.3

2.3

2.4

2.4

2-4

3

Setup

Unwrapping
Locating Components

Activating Open-Thermocouple Detection
Setting Gain
Setting

Selecting
Selecting a

Setting

Using

Using

Installing
Setting

Power

and

Inspecting

.................................

.........................................

the

Output

Up

Power

+5

External

the

Setting the Jumper
Setting

Notes

Jumpers

a

CJC

Channel

DAS

Board

.....................................

V

and

f12 V External Supplies

+5 V Only

a

PG-408A

+5

V

Jumper

the

Jumper

......................................

Your

.............................

.............................

Channel

DC/DC Converter

.............................

for

for

Board

...................

.................

.......................

................

...........................

................

an

EXP.16

an

EXP-lG/A (Jumper

...................

J9)

.......

3.1

3.2

3.3

3.3

3.5

3.5

3.5

3-7

3.7

3.7

3.7

3.8

3.8

3.9

3.9

4

Wiring and Cabling

Using

the

Main

1/0

Connectors

Connecting

Using

Using

Using

Using

Avoiding Ground Loops

5

Calibration

Equipment Requirements

Instrumentation Amplifier Calibration
CJC Circuit Calibration

6

Troubleshooting

Problem Isolation

Common Problems
Technical Support

Multiple EXP-16s

EXP-16s or EXP-lG/As

Series

Boards

EXP-16s or EXP-16/As

DAS-SPGA/pCDAS-8PGA

EXl-16s

Boards

Board

.......................................

EXP-16s

........................................

.................................

and

EXF-16/As

and

EXF'-16/As

................................

................................

.....................................

and

Solutions

....................................

..........................

or

EXP.l6/As

with

with

Board

with

with

...............................

........................

...............

DAS-16/1600/1400/1200

a

.................

DAS-gAO/LT

aDASCON-1

....................

4.

4.2

4.2

4.4

4-5

4-5

4.6

5.1

5.2

5.4

6.

6.2

6.4

1

1

iv

A

Specifications

B

Connector Pin Assignments

C

Operating Notes

Input Channel Selection
Software

D

Channel Numbers

Channel Numbering
Channel Numbering

Index

Support for Low-Level Devices

with

DAS-8 Calls

for

Software

for

8-Channel DAS

for

16-Channel DAS

.................

..................

Boards

Boards

...........

..........

C.
C.2

D-

D-2

1

1

List

of

Figures

Figure 2.1
Figure 2.2
Figure 3.1
Figure
Figure
Figure

Figure

Figure 4.2

Figure

Figure 4.4

Figure 4.5
Figure 4.6
Figure
Figure
Figure 6.1
Figure

Figure D.1

Figure D.2 . Analog Input Channels

3.3

3.4

4.1

4.3 . S-1600 Cable Wiring

Block Diagram

.

Input Circuit

.

Locations

.

Locations

3.2

.

Gain Switch (set

.

Locating

.

Board Socket

Ph

Assignments

JlmdJ2

Daisy

Chain

EXP-l6/A

C-1800)

A Daisy Chain

Series board with

Eight EXP-16s

Connecting a Grounded Signal Source

Connecting a Floating Signal Source
Locations
Locations
EXP-16

.

Pin Assignments

.

Analog

or

J1

adJ2

Input Channel Numbering

Software Control

5.1

5.2

B.1

.

.

.

.
.
.

.

.

of

anEXP-16 andEXP.l6/A

for

Each Analog Input Channel

of

Em-16 Key Components

of

EXP-l6/A

for

gain

Fin

1

on the

PG-408A

.........................

of

Main

.............................

of

a

DAS

and

an

..............................

.......................

of

a DAS-16/1600/1400/1200

or

of

Em-16 Calibration Components

of

EXP-l6/A Calibration Components . 5-3

EXP-l6/A System Components

for

Main

.............................

........

Key

Components

of

50)

..............

and

I/O

Connectors

Board with Em-16
STA-XX (all cables

an

STA-XX

EXP- 16fAs

and up

............

.........

..........

1/0

Connectors

for

.....................

....................

....

....

......

or

are

to

...

.....

2.1

2.2

3.2

3.2

3.3

3.8

4-1

4-2

4.3

4.3

4.6

4.6

5.3

6.1

B-1

D-2
D-4

List

of

Table 3.1
Table

3.2

Table

6.1

TabIe

A.1

TabIe

A.2

TabIe A.3
TabIe A.4
Table

A.5

Table A.6
TabIe

D.1 .

Table D.2

Tables

.

Recommended Gains

Channel Selection Configurations

.

.

Problems

Analog

.

Cold-Junction Compensation

.

Gain Relationships

.

Power Requirements

.

Environmental Specifications

.
.

Physical Specifications

Channels

Channels

.

and

Suggested Solutions

Data

.............................

in

Maximum

Configuration

in

Maximum EXP-16 Series

Configuration

........................

........................

........................

for

Thermocouple Types . .

.............

............

...............

......................

...............

....................

EXP-8/800

3-4

3.6

6.2

A-1

A-1
A-2
A-2

A-2

A-3

D-1

D-3

V

The

EXP-16

program, and use the
guide

and

EXP-16IA

also

explains how to calibrate and troubleshoot.

EXP-

UserS

16 and

Preface

Guide

describes how

EXP-

16/A expansion accessories. This

to

set

up,

install,

This guide serves data acquisition
programmers, and other users responsible for
wiring
and instructions contained in this guide, you
data-acquisition principles

The

signals

to the Em-I6

and

EXP-I6

Chapter
applications, and accessories.

Chapter

EXP-I

Chapter
Chapter

Em-16
Chapter
Chapter

your
technical

Appendix

and

EXP-16IA

1

provides an overview

2

provides a

6/A, including

3

describes how to set up

4

describes how

or

EXP-l6/A.

5

describes

6

explains how

Em-16 or

functional

bIock

calibration procedures.

EXP-l6/A

support.

A

lists

the specifications

system

and

EXP-l6/A. To

your

WserS

to

Guide

diagrams.

to

connect accessories and

troubleshoot problems

and

designers, engineers,

DAS

board.

is

of

the

hardware features, typical

description

your

EXF-16

provides information

for

the

setting

must

organized as follows:

up, cabling,

follow the information

be

familiar with

of

the

EXP-16 and

or

EXP-l6/A.

EXP-16

signals

that

and

to

may

arise

on

obtaining

EXP-l6/A.

and

your

with

Appendix B lists

the

Em-I6

Appendix
operation

and

C contains misceltaneous additional

of

the EXP-16 and EXP-l6/A.

the

pin

assignments for the

EXP-l6/A.

main I/O

material

connectors of

on the

vii

Appendix D explains

purposes

An

index

of

software

completes

how

control

this

manual.

to

assign logical

of

your

EXP-16

channel

numbers

or EXF'-16/A.

for

viii

Overview

The

En-

16 is

an

expansion interface board equipped with half-inch

standoffs. The EXP-l6/A

plastic encIosure.

An

Em-16
single signal for amplification and input to one single-ended input
channel
multiplexed signal at switch-selectable gains, and
contains circuitry for filtering, current
detection.
circuit

or

EX€-16/A can multiplex 16 analog input signals into a

of

a data acquisition

The

two EXPs

for

correcting thermocouple readings.

is an expansion interface board mounted in a

also

system.

contain

The

two

EXPs can

measuring,

a

CJC

(cold junction compensation)

amplify

each

of

their

16 inputs

and open-thermocouple

the

Features

Features

This chapter briefly describes the EXP-16
features, applications, and accessories.

Principal features

a

Expands a single-ended analog input channel
system into 16 differential inputs

Works

0

DAS-1200, DAS-1400, and DAS-1600 Series

a

Offers

and T thermocouples

0

Offers

a

Contains terminah

with the Keithley

a

open-thermocouple detection at each

CJC

of

an

Em-16

channel

for a current-measuring resistor at each input

or

EXP-16/A

MetraByte

that

supports the use of

DAS-8,

and

EXP-16/A

are

as

follows:

of

any

data

DAS-800,

boards

type B,

E,

input

and

their

acquisition

DAS-115,

J,

K,

R,

S,

1-1

Connects

provide up

in

a daisy chain

to 128

analog

of

up to eight

input

channels

EXF-16s

or

EXP-l6/As

to

Applications

Typical applications for EXP-16s and

Accessories

Accessories

Contains
switch-seIectable gain settings

Offers filtering at each input

Input channel expansion
Energy management
Signal amplification
Signal conditioning

C-1800

or

an

for

is

a

DAS-800

instrumentation amplifier with a choice

the

EXP-16

cable for connecting

Series board, or

and

EXP-l6/A

to

Em-l6/As

an

EXP-

another

are

as

16

or

EXP-16

of

are

as

follows:

follows:

EXP-l6/A

or

EXP-16/A.

eight

to

a

DAS-8

1-2

S-1600

D

AS

PG-408A

EXP-l6/A

board.

Refer

to

Em-16

is

a cable

-

1 6/ 1

ZOO/

is

Chapter 4 for instructions
or

EXP-l6/A.

for

connecting

1400/ 1600

a

snap-in DC/DC converter

that

is used with a

Series board.

an

EXP-16

or

EXP-l6/A

module

for

an

EX€-16

to

DAS-SA0/16/1200/1400/1600

on

attaching these accessories

a

or

Series

to

an

Overview

2

Functional

This

chapter

EXP-lWA.

describes

Figure

2-1

features

shows

and

the

Description

operating

block

options

diagram.

76543210

of

the

X-

EXP-16

and

Figure

2-1.

Block

Diagram

of

an

EXP-16

and

EXP-16IA

2-1

Input

Circuits

Each input channel
configured as shown

of

an

Em-16 or EXP-lGIA contains circuitry

in

Figure

signal filtering, and terminals

100

Screw

Tenninal

CHAN

for

nHI

-

Input Holes
Channel

Solder

Gap

0

I

T T

Mounting

n

Current

L

Screw

Terminal

CHAN

far

n

LO

Figure

sgzF

2-2.

Input Circuit

2-2

to offer open-thermocouple detection,

for

a current-measuring shunt resistor.

MR

-15

V

CHAN

80

HZ

Filter

for

wv

1

, ,--

111

Im

1

C,l.OpF

Filter

Capacitor

T

1

CHAN

-

for

Each

Analog

Input Channel

n

n

HI

LO

to

to

MUX

r

b

MUX

Open-Thermocouple

Each input circuit uses biasing resistors
detection. Note that the
common-mode voltages on
open-thermocouple detection,
thermocouple by slowly changing the
voltage
can develop a software routine to sense
threshold and flag the open thermocouple. Refer
Open-Thermocouple Detection”
the

2-2

is

much larger than the voltage a thermocouple can produce, you

solder

gaps.

Detection

10

to

enable open-thermocouple

ki2

resistor on

the

thermocoupIe. When you activate

the

biasing resistors respond to

on

input

page

the

low input allows

voltage

any

input

to

3-3

for

instructions

to

-15

voltage above a certain

“Activating

Functional

an

open

V.

As

this

on

bridging

Description

Signal Filtering

The

1.0

pF

filter capacitor and the two
filter for the input signal. If you
particular channel, you can remove the capacitor
that channel.

Current-Measuring Resistor

A

pair

of

mounting holes for a current-measuring

the

screw terminals

to

you

allow

size and power rating for the current
find it more convenient to place the resistor across the channel screw
terminals rather than in the mounting holes.

to solder

the

Multiplexer

An

Em-16

analog

be

to
TTL/CMOS-compatible address on the differential-channel-select lines,
shown
channel

or

input

sampled

in

Figure

1,2h

EXP-I6/A

channels

for

multiplexing

2-1.

selects channel

need

faster settling response for a

for

each channel. The holes

resistor into place.

you

multiplexes signals

into

one signal for the

is

selected

An address

of

Oh selects channel

2,

and

so

1

kn

resistors make

You

must determine the resistor

want

to

from

analog

by

a 4-bit

on.

up

an 80

to

disable the filter

resistor

are

measure.

is

located next

plated-through to

You

may also

the 16 differential

output.

Each channel

0,

lh

selects

Hz

for

Multiplexer

When

you

use

an EXP-16

con&ol the address
outputs are activated

and

guide
Refer to Appendix D for information

channels for software control.

Appendix C

with

or EXl-lG/A with a DAS-8 Series

by

for

DAS-8

DAS-8

digital

CALL

more information).

board,

outputs OP1
Mode 14 (see the DAS-8 user’s

on

the

numbering

to

OP4.

The

of

expansion

DAS-8

you

2-3