Tektronix Keithley DAS-8 External DAS Driver Users Guide

DAS-8
External DAS Driver

USER’S GUIDE

DAS-8 External DAS Driver

User’s Guide

Revision D - December 1994

Part Number: 59136

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 in this manual is believed to be accurate and reliable. However, Keithley
Instruments, Inc., assumes no responsibility for its use or 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 Keithley Instruments, Inc.

KEITHLEY INSTRUMENTS, INC., SHALL NO T BE LIABLE FOR ANY SPECIAL, INCIDENTAL,
OR CONSEQUENTIAL DAMAGES RELATED TO THE USE OF THIS PRODUCT. THIS
PRODUCT IS NOT DESIGNED WITH COMPONENTS OF A LEVEL OF RELIABILITY
SUITABLE FOR USE IN LIFE SUPPORT OR CRITICAL APPLICATIONS.

Refer to your Keithley Instruments license agreement for specific warranty and liability information.

MetraByte and EASYEST AG are trademarks of Keithley Instruments, Inc. VIEWDAC,
EASYEST LX, and ASYST are re gistered trademarks of Keithley Instruments, Inc. All other brand and
product names are trademarks or registered trademarks of their respective companies.

© Copyright Keithley Instruments, Inc., 1989 to 1994.

All rights reserved. Reproduction or adaptation of any part of this documentation beyond that permitted
by Section 117 of the 1976 United States Copyright Act without permission of the Copyright owner is
unlawful.

Keithley MetraByte Division

Keithley Instruments, Inc.

440 Myles Standish Blvd. Taunton, MA 02780

FAX: [phone]

Telephone: [phone]

●

Preface

The DAS-8 External DAS Driver allows you to use Keithley MetraByte
DAS-8 Series boards with the following Keithley MetraByte data
acquisition and analysis software:

●

VIEWDAC
EASYEST LX

●





●

EASYEST AG

●

ASYST





This manual provides the information needed to use the DAS-8 External
DAS Driver with data acquisition and analysis software. Use this manual
in conjunction with your board user’s guide and with the documentation
for the expansion accessories and data acquisition software you are using.

Note:

The DAS-8 External DAS Driver may support options your
software does not; likewise, your software may support options this
external driver does not.

v

If you need help, contact your local sales office or the Keithle y MetraByte
Applications Engineering Department between 8 am and 6 pm (Eastern
Time), Monday through Friday:

Keithley MetraByte

Applications Engineering
440 Myles Standish Boulevard
Taunton, Massachusetts 02780

Telephone [phone]

Telex 503989

FAX [phone]

vi

Table of Contents

Preface

1

Using the DAS-8 External DAS Driver

Supported Hardware. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Options Supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Files on Disk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Quick Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Setting up the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Running the Configuration Program. . . . . . . . . . . . . . . . . . . . . 4

Loading the DAS-8 External DAS Driver. . . . . . . . . . . . . . . . . 5

Accessing the DAS-8 External DAS Driver . . . . . . . . . . . . . . . 6

Using the Configuration Program . . . . . . . . . . . . . . . . . . . . . . . . . 7

Menu Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Special Purpose Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Exiting the DAS-8 Configuration Program. . . . . . . . . . . . . . . 10

Configuring the DAS-8 External DAS Driver from DOS . . . . . . 11

DAS-8 External DAS Driver Characteristics. . . . . . . . . . . . . . . . 12

Counter/Timer Channels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Logical Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Clocking and Triggering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

EXP-16 and EXP-GP Expansion Accessories . . . . . . . . . . . . 13

Physical and Logical Channels . . . . . . . . . . . . . . . . . . . . . 14

Internal Clocking with Expansion Accessories . . . . . . . . . 16

Interrupt-Mode Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Software Interrupt Vectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

DAS-8 External DAS Driver Error Messages . . . . . . . . . . . . . . . 18

List of Figures

Figure 1. Analog Input Channels . . . . . . . . . . . . . . . . . . . . . 15

iii

List of Tables

Table 1. Configuration Program Menu Items . . . . . . . . . . . . 7

Table 2. Analog Input Ranges . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 3. Gains Available for DAS-8PGA,

µ

CDAS-8PGA,

and DAS-8/AO Boards . . . . . . . . . . . . . . . . . . . . . . 9

Table 4. Configuration Menu Special Keys. . . . . . . . . . . . . 10

Table 5. Command-Line Options . . . . . . . . . . . . . . . . . . . . 11

Table 6. Physical and Logical Channels

(Maximum Configuration). . . . . . . . . . . . . . . . . . . 14

Table 7. Interrupts and Environment Strings. . . . . . . . . . . . 17

Table 8. Error Messages from the DAS-8 External DAS

Driver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

iv

Table 1. Configuration Program Menu Items . . . . . . . . . . . . 7

Table 2. Analog Input Ranges . . . . . . . . . . . . . . . . . . . . . . . . 8

Table 3. Gains Available for DAS-8PGA,

µ

CDAS-8PGA, and
DAS-8/AO Boards9

Table 4. Configuration Menu Special Keys. . . . . . . . . . . . . 10

Table 5. Command-Line Options . . . . . . . . . . . . . . . . . . . . 11

Table 6. Physical and Logical Channels
(Maximum Configuration)14

Table 7. Interrupts and Environment Strings. . . . . . . . . . . . 17

Table 8. Error Messages from the DAS-8 External DAS Driver
18

Figure 1. Analog Input Channels . . . . . . . . . . . . . . . . . . . . . 15

µ

Using the DAS-8

External DAS Driver

The DAS-8 External DAS Driver allows your VIEWDAC,
EASYEST LX, EASYEST AG, or ASYST application program to
exchange data with DAS-8 Series boards. This document describes how
to use the DAS-8 External DAS Driver.

Supported Hardware

The DAS-8 External DAS Driver supports the following Keithley
MetraByte data acquisition (DAS) boards:

●

DAS-8

●

DAS-8PGA

●

CDAS-8PGA

DAS-8LT

●

●

DAS-8/AO

Options Supported

The DAS-8 External DAS Driver supports the following options:

●

Analog input

– Eight 8- or 12-bit onboard channels
– Up to 128 channels through EXP-16 and EXP-GP expansion

accessories

– Programmable gains for DAS-8PGA, µ CDAS-8PGA, and

DAS-8/AO boards

– Channel-gain arrays of up to 256 entries

1

– Synchronous-mode and interrupt-mode operations
– Single-cycle and continuous buffering for interrupt-mode

operations using single or double buffers
– Internal and external clocking
– Internal and external triggering

Analog output (DAS-8/AO)

●

– Two 12-bit analog output channels
– Synchronous-mode and interrupt-mode operations
– Single-cycle and continuous buffering for interrupt-mode

operations using single or double buffers
– Internal and external clocking
– Internal and external triggering

●

Digital input

– Three digital input bits
– Synchronous-mode and interrupt-mode operations
– Single-cycle and continuous buffering for interrupt-mode

operations using single or double buffers
– Internal and external clocking
– Internal and external triggering

Digital Output

●

– Four digital output bits
– Synchronous-mode and interrupt-mode operations
– Single-cycle and continuous buffering for interrupt-mode

operations using single or double buffers
– Internal and external clocking
– Internal and external triggering

2 Using the DAS-8 External DAS Driver

Files on Disk

The driver disk contains the file DAS8.EXE. DAS8.EXE controls the
boards and allows communication between an application program and
the DAS-8 Series boards. DAS8.EXE executes as a
terminate-and-stay-resident (TSR) program that occupies a small amount
of memory in your computer.

Quick Start

This section briefly describes how to configure, load, and access the
DAS-8 External DAS Driver.

Setting up the Board

Refer to your board user’s guide for information on setting the
jumpers/switches for the base address, analog input configuration
(single-ended or differential), interrupt (IRQ) setting, and the analog
output ranges. Remember these settings when you use the DAS-8
External DAS Driver configuration program.

The following are a few important connections to keep in mind for DAS-8
Series boards:

●

Internal clock
– Connect CNT 2 OUT to CNT 1 CLK
– Connect CNT 1 OUT to INT IN
External clock - Connect to INT IN pin

●

External trigger - Connect to IP1

●

If you are using an EXP-16 or EXP-GP expansion accessory , refer to page
16 for more information on using the internal clock.

3

Running the Configuration Program

The DAS-8 External DAS Driver is set up for the following default
configuration:

●

Board type = DAS-8
Base address = 300h

●

●

Interrupt level = IRQ 2

●

A/D range = Bipolar
A/D resolution = 12-bit

●

Number of EXP-16s = 0

●

●

Number of EXP-GPs = 0

●

CJR channel = None
Set Channel Gain = N/A (no EXPs configured)

●

Number of boards = 1

●

LT clock option = N/A

●

●

PC bus clock = 4.77 MHz
D/A range channel 0 = N/A (for DAS-8)

●

D/A range channel 1 = N/A (for DAS-8)

●

You must run the configuration program or configure the driver from
DOS if your board’s settings differ from these default settings. In
addition, whenever you change the hardware or software settings, you
must run the configuration program or reconfigure the driver from DOS in
order for the external DAS driver to function properly.

Notes:

Each memory resident image of the DAS-8 External DAS Driver

can support two DAS-8 Series boards. If you are using more than one
DAS-8 Series board, you must configure the parameters for each board,
ensuring that the base address and interrupt level do not conflict between
the two boards.

4 Using the DAS-8 External DAS Driver

Perform the following steps to run the configuration program:

1. Create a DAS8 subdirectory on your hard disk. For example, at the
DOS prompt, enter the following:

MKDIR DAS8

2. Copy DAS8.EXE from the driver disk into the DAS8 directory.

3. Enter the following at the DOS prompt:

CD \DAS8
DAS8 –MENU

4. Configure the board parameters using the configuration program, as
described on page 7.

Note:

If you wish, you can also configure the DAS-8 External DAS
Driver from DOS instead of using the configuration program; refer to
page 11 for more information.

Loading the DAS-8 External DAS Driver

You must load the DAS-8 External DAS Driver each time you start up
your computer in order for an application program to recognize it. The
external DAS driver remains in memory until the computer is turned off
or rebooted.

To load the DAS-8 External DAS Driver, access the directory containing
DAS8.EXE and enter the following at the DOS prompt:

DAS8

5

Notes:

whenever you start the computer by adding the preceding line to your
AUTOEXEC.BAT file.

If you want to access more than two boards, load the driver multiple times
and use configuration files to recall the configurations.

For example, to access three DAS-8 boards you could create two
configuration files: DAS8-1.CFG and DAS8-2.CFG. DAS8-1.CFG
contains the configuration data for two boards at addresses 300h and
310h, and DAS8-2.CFG contains the configuration data for a single
DAS-8 Series board at address 340h. To load these drivers, use the @
command line option, as follows:

DAS8 @DAS8-1.CFG
DAS8 @DAS8-2.CFG

You can also load the DAS-8 External DAS Driver automatically

Accessing the DAS-8 External DAS Driver

Some application programs access the DAS-8 External DAS Driver
automatically . For information on accessing e xternal D AS dri vers, see the
documentation for your application program.

If you are using the ASYST program, perform the following steps to
access the DAS-8 External DAS Driver:

1. After loading the DAS-8 External DAS Driver, boot ASYST version

2.10 or greater and permanently load the Ext DAS Driver Support
system overlay from the Data Acquisition menu. ASYST
automatically searches for and creates a DAS device called DAS8.

2. Enter the following at the OK prompt to make DAS-8 the current

device:

DAS8

6 Using the DAS-8 External DAS Driver

Using the Configuration Program

This section describes the configuration program’s menu items and
special purpose keys, and how to exit from the configuration program.

Menu Items

When you run the configuration program, the configuration menu is
displayed. The menu options, choices, and default values are listed in
Table 1.

Table 1. Configuration Program Menu Items

Menu Item Choices Default Value

Board Type DAS-8, DAS-8PGA, µ CDAS-8PGA

1

1,2

1

Base I/O Address
Interrupt Level
A/D Range
A/D Resolution
Number of EXP-16s
Number of EXP-GPs
CJR Channel (for

EXPs)
Set Channel Gains

(for PS/2  ), DAS-8LT, DAS-8/AO
200h to 3F0h (in multiples of 10h)
IRQ 2, 3, 4, 5, 6, 7
Unipolar, Bipolar
12-bit binary, 8-bit binary
0, 1, 2, 3, 4, 5, 6, 7, 8
0, 1, 2, 3, 4, 5, 6, 7, 8

1,2

3

4

1,5

1,4

Depends on the number of EXP-16s and
EXP-GPs selected

1

.5, 1, 2, 10, 50, 100, 200, 1000

DAS-8

300h
IRQ 2
Bipolar
12-bit
0
0
None

1 (for all channels)

(for EXPs)
Number of Boards

LT Clock Option (for
DAS-8 and for the

1

1, 2
External (IBM PC bus clock),

Internal (1 MHz clock)

1

1
Internal

DAS-8LT)
PC Bus Clock Computer’s bus speed, which varies

according to the computer you are using

4.77 MHz

1,6

7

Table 1. Configuration Program Menu Items (cont.)

Menu Item Choices Default Value

±

±

D/A Range Channel 0
(for DAS-8/AO)

D/A Range Channel 1
(for DAS-8/AO)

Notes

1

Choice must match the board’s settings.

2

If you are using more than one DAS-8 Series board in your system, ensure that the base address

and interrupt channel are unique for each board.

3

This option is available for DAS-8PGA, µ CDAS-8PGA, and DAS-8/AO boards only.

4

A 12-bit conversion takes a maximum of 35 µ s to complete, while a short-cycle, 8-bit

conversion takes a maximum of 25 µ s.

5

When EXPs are used, you cannot use the board's digital outputs.

6

This option is available only for the DAS-8 and for the DAS-8LT when using the External LT

4 to 20 mA, 0 to 5 V, 0 to 10 V, ±2.5 V,
±5 V, ±10 V

1

4 to 20 mA, 0 to 5 V, 0 to 10 V, ±2.5 V,
±5 V, ±10 V

1

0 to 5 V

0 to 5 V

clock option; these boards derive their clock from the IBM PC bus clock.

Depending on the A/D input range type (unipolar or bipolar) you choose,
the input ranges shown in Table 2 are available.

Table 2. Analog Input Ranges

Input Range
Type

DAS-8PGA DAS-8 DAS-8LT DAS-8/AO µ CDAS-8PGA

Unipolar 0 to 10 V N/A N/A 0 to 10 V 0 to 10 V
Bipolar

10 V ± 5 V ± 5 V ±10 V

10 V

As Table 3 shows, available programmable gains (supported on the
DAS-8PGA, µ CDAS-8PGA, and DAS-8/AO) and their corresponding
gain codes are dependent on the A/D input range type.

8 Using the DAS-8 External DAS Driver

±

±

±

±

±

Table 3. Gains Available for DAS-8PGA,

Unipolar
Range Gain

0 to 10 V X1 9
0 to 1 V X10 11
0 to 100 mV X100 13
0 to 20 mV X500 15

Gain
Code

When you select the Set Channel Gains menu item, the channel
assignments window is displayed. This menu allo ws you to select the gain
of each channel. To set a channel's gain, first select the EXP accessory
using the up and down arrows and the [Home] and [End] keys, then press
[Enter] to open another window.

For EXP-16s, pressing [Enter] cycles through the allowable gains. For
EXP-GPs, you can set each channel's gain individually along with a
board-level gain. If the channel is a CJR channel, no gain choices are
available. Press [Esc] to return to the channel assignments windo w. When
you have set all channels to the desired gain, press [Esc] again to return to
the main menu.

µ

CDAS-8PGA, and DAS-8/AO Boards

Bipolar
Range Gain

10 V X1 8
5 V X2 0
500 mV X20 10
50 mV X200 12
10 mV X1000 14

Gain
Code

The gains specified in this option are used only if the application software
supports DAS Driver Specification version 2.00. If the application
software does not support version 2.00, set the gain for channel 0 only. In
this case, the gain of all channels is relative to the A/D range type setting
(unipolar = 0 to 10 V, bipolar = ± 5 V) and the gain of channel 0. If the
gain of the other channels differs from the gain of channel 0, you must
compensate for the difference.

9

Special Purpose Keys

Table 4 describes the keys used for special purposes in the configuration
program.

Keys Description

[w] Write a configuration save file. This option allows you to

[q] Quit the configuration program without loading the

[d] Reset the driver settings to their default values.

Table 4. Configuration Menu Special Keys

save the current configuration to a file for future use.

driver.

[Esc] Exit the configuration menu with the option of saving

the current settings and loading the driver into memory.
This key is also used to exit the Channel Assignments
menu.

[Tab] Toggle between boards 1 and 2 when two boards are

being configured.

[?] Invoke help on the current menu item.

Exiting the DAS-8 Configuration Program

To exit the configuration program without saving any changes, press [q].
Otherwise, to exit the configuration program press [Esc]. The following
prompt is displayed:

Do you want to permanently save this configuration?
[Y/N]

T ype [Y] to sa ve the configuration; type [N] if you do not w ant to sav e the
configuration settings. If the configuration is saved, the program displays
the message:

Remembering...

10 Using the DAS-8 External DAS Driver

Then, you are prompted with the following message:

Exit Configuration Program? [Y/N]

T ype [Y] to exit from the configuration program; type [N] to remain in the
configuration program.

Configuring the DAS-8 External DAS Driver from DOS

If you wish, you can also change the configuration of the DAS-8 External
DAS Driver using DOS command-line options instead of using the
configuration program. The command-line syntax is as follows:

DAS8 [

bd #1 options

],[

bd #2 options

The command-line options are described in Table 5.

Table 5. Command-Line Options

Command Purpose

-a### base address = ### (in hex)

-i# Set IRQ level = # (2 to 7)

-ca+ Set A/D range type to Unipolar
(DAS-8PGA only)

-ca- Set A/D range type to Bipolar

-12bit Set A/D resolution to 12-bit

-8bit Set A/D resolution to 8-bit

-z0# Set D/A range of channel 0 = #
(DAS-8/AO only)

-z1# Set D/A range of channel 1 = #
(DAS-8/AO only)

] [-menu ]

-bs# Set PC bus speed = # (DAS-8 or
DAS-8LT only)

-das8 Set board type = DAS-8

-pga Set board type = DAS-8PGA

11

Table 5. Command-Line Options (cont.)

Command Purpose

-ucdas8 Set board type = µCDAS-8PGA

-ltb Set board type = DAS-8LT (bus clock)

-lti Set board type = DAS-8LT (internal
clock)

-out Set board type = DAS-8AO

-f Recall defaults

-h or ? help

-menu invoke menu driven setup

@xxxx Indicates use of response file xxxx. A

response file is an ASCII file containing
the command-line options for the
driver.

DAS-8 External DAS Driver Characteristics

The following sections describe the various attributes of the DAS-8
External DAS Driver and the restrictions imposed by the external DAS
driver on various modes of operations and resources.

Counter/Timer Channels

DAS-8 Series boards have three timer/counter channels: counters 0, 1,
and 2. The DAS-8 External DAS Driver uses counter 1 and counter 2 for
timing analog input, analog output, and digital I/O operations.

Logical Signals

A logical signal is an incoming signal that takes on the logical values of 0
or 1. For the DAS-8 External DAS Driver, a logical low signal is 0 V and
a logical high signal is 5 V.

12 Using the DAS-8 External DAS Driver

Clocking and Triggering

The characteristics of clocking and triggering with the DAS-8 External
DAS Driver are as follows:

● Internal Clock - Conversions begin without waiting for an external

event and proceed at the specified rate until finished.

● External Clock - The software waits for a rising edge signal at INT

IN (pin 24) before starting a conversion. Acquisition proceeds and is
paced by the external clock until the requested amount of data has
been acquired.

The clocking signal is positive, edge-sensitive.

● External T rigger - The software waits for a logical low signal at the

IP1 (pin 25) before starting the acquisition. Acquisition then proceeds
at the specified rate until finished.

The triggering signal is low, level-sensitive.

EXP-16 and EXP-GP Expansion Accessories

DAS-8 Series boards provide eight analog input channels. To increase the
number of channels to 128, you can connect up to eight EXP-16 or eight
EXP-GP expansion accessories. Each EXP-16 accessory multiplexes 16
differential inputs into one output signal. Each EXP-GP accessory
multiplexes eight inputs into one output signal.

When using expansion accessories, ensure that the DAS-8 Series board is
set up for single-ended operation.

To ensure that the DAS-8 External DAS Driver reads the channel
numbers correctly, you must attach all EXP-16 expansion accessories
first, followed by all EXP-GP expansion accessories. You can also use the
remaining onboard channels using a screw termination panel. Refer to
your board and accessory documentation for more information.

Note: If you are using a screw termination panel with expansion

accessories, the channels used by the EXP-GPs and EXP-16s are
available on the panel; ho wever, it is important not to connect any signals
to these inputs.

13

Physical and Logical Channels

You can daisy chain multiple EXP-16 and EXP-GP accessories to a
DAS-8 Series board, provided that each expansion accessory is assigned
to a distinct analog input channel on the DAS-8 Series board. Use Output
Channel jumper J4 on the expansion accessory to assign one of the analog
input channels on the DAS-8 Series board to the output signal on the
accessory board.

To refer to the channels, a scheme of physical and logical channels is
used. A physical channel is the analog input channel on the DAS-8 Series
board to which the expansion accessory is assigned. The logical channel
is the channel that the application software uses to access channels on the
DAS-8 Series board and any expansion accessories. The logical and
physical channel assignments are displayed in the configuration program.

Table 6 lists the physical channels on the DAS-8 Series board and the
corresponding logical channels associated with each expansion accessory.

Table 6. Physical and Logical Channels

(Maximum Configuration)

Physical Analog
Input Channel on
DAS-8 Series
Board

0 0 to 15 0 to 7
1 16 to 31 8 to 15
2 32 to 47 16 to 23
3 48 to 63 24 to 31
4 64 to 79 32 to 39
5 80 to 95 40 to 47
6 96 to 111 48 to 55
7 112 to 127 56 to 63

14 Using the DAS-8 External DAS Driver

Logical Channels

EXP-16 EXP-GP

Figure 1 illustrates the use of one EXP-16 expansion accessory, two
EXP-GP expansion accessories, and the five remaining onboard channels.
The channels on the EXP-16 attached to analog input channel 0 are
referred to in software as logical channels 0 to 15; the channels on the
EXP-GP attached to analog input channel 1 are referred to in software as
logical channels 16 to 23; the channels on the EXP-GP attached to analog
input channel 2 are referred to in software as logical channels 24 to 31;
the remaining five onboard analog input channels (3, 4, 5, 6, and 7),
which you can access using a screw termination panel, are referred to in
software as logical channels 32, 33, 34, 35, and 36.

EXP-16
channels
0 - 15

EXP-GP
channels
16 - 23

EXP-GP
channels
24 - 31

DAS-8
Series Board

0
1
2
3
4
5
6
7

Onboard
channels
32 - 36

Figure 1. Analog Input Channels

Note: Digital outputs DO0 to DO3 are used to select the current channel

on the expansion accessory. If an analog input operation is active, digital
output operations are not allowed; if a digital output operation is activ e, a
single-mode analog input operation is allowed but the digital output
values are affected.

15

Internal Clocking with Expansion Accessories

If you are using one EXP-16, no EXP-GPs, and no screw termination
panels, solder the connections to the EXP-16 board as follows:

1. Jumper hole 6 to hole 4.

2. Jumper hole 5 to hole 24.

Excessive cable length can cause problems with internal clocking. These
problems can occur with either one expansion accessory and a screw
termination panel or multiple expansion accessories with or without a
screw termination panel. One solution to these problems is to shorten the
route the timing signals must travel by jumpering together the needed
signals in the first ribbon cable connected to the DAS-8 Series board as
follows:

1. Locate the following on the ribbon cable:
– CNT2 OUT - pin 6 (brown wire)
– CNT1 CLK - pin 4 (purple wire)
– CNT1 OUT - pin 5 (white wire)
– INT IN - pin 24 (black wire)

2. Decide which end of the cable to connect to the DAS-8 Series board.

3. Cut the cable so the above signal wires are exposed at the end of the
cable that connects to the DAS-8 Series board.

4. On the end of the cable that connects to the DAS-8 Series board,
connect the brown wire (CNT2 OUT) to the purple wire (CNT1
CLK). Leave the brown and purple wires on the other end of the cable
unconnected.

5. On the end of the cable that connects to the DAS-8 Series board,
connect the white wire (CNT1 OUT) to the black wire (INT IN).
Leave the white and black wires on the other end of the cable
unconnected.

16 Using the DAS-8 External DAS Driver

Interrupt-Mode Operations

Interrupt mode is supported for analog input, analog output (DAS-8/A O boards
only), and digital I/O operations. If any of these interrupt-mode operations is
active, the corresponding synchronous-mode function cannot be used. For
example, if an interrupt-mode analog input operation is active,
synchronous-mode analog input operations are not allowed. Also, you cannot
start an interrupt-mode operation while another interrupt-mode operation is
active.

Software Interrupt Vectors

The DAS-8 External DAS Driver uses two software interrupt vectors to
communicate with the application program. The interrupt vectors used are
two of the MS-DOS “user interrupts” (interrupts 60h to 67h). To ensure
that conflicts with other devices, hardware, or programs do not exist, you
can set each of the interrupt vectors to use an interrupt number that is
different than from the default.

You can change the interrupt vector numbers by using the SET command
from DOS. This command saves a string in the DOS environment that the
driver searches for on loading. These strings are specified in Table 7.

Table 7. Interrupts and Environment Strings

Interrupt Default Interrupt

Number

Device linking vector 66h DAS DS=xx
Critical error vector 65h DAS CE=xx

Notes

1

xx is between 60h and 67h.

Environment

1

String

17

DAS-8 External DAS Driver Error Messages

Table 8 lists the error messages that may occur during operation of the
DAS-8 External DAS Driver.

Table 8. Error Messages from the DAS-8 External DAS Driver

Error
Number

0 No error No error message.
1 Function not supported A function was requested that is not supported by the

2 Function out of bounds A function number not defined by the DAS-8 External

3 Non-valid board number A board number that is out of the range of configured

4 Non-valid error number A non-valid error number was detected by the external

5 Invalid channel number A start channel greater than a stop channel or a

Error Message Description

DAS-8 External DAS Driver.

DAS Driver was requested.

boards was requested. This driver supports a
maximum of two boards.

DAS driv er function “REPORT ERROR MESSAGE.”
A request was made for an error message string that is
not defined.

channel greater than the maximum channel number
was detected by an analog input operation. To prevent
this error, do not request an analog input operation
with a start channel greater than the stop channel or
with any channel greater than the maximum channel
number. An easy way to determine the maximum
channel number is as follows:

(max chan #) = 7 + 15 * (# of EXP-16s)

6 Device not initialized State of the driver is irregular . Execute the D AS Dri ver

function DEVICE INIT. This function initializes the
DAS-8 External DAS driver and the DAS-8 Series
board for subsequent operations.

7 Digital output not

initialized

18 Using the DAS-8 External DAS Driver

A digital output operation was started before the
digital output section of the board was initialized.

Table 8. Error Messages from the DAS-8 External DAS Driver (cont.)

Error
Number

8 Digital input not

9 A/D not initialized An analog input operation was started before the

10 Output bits in use A digital output operation was attempted when the

11 Board not found at

12 D/A not initialized An analog output operation was started before the

13 Interrupt overrun

Error Message Description

A digital input operation was started before the digital

initialized

configured address

condition

input section of the board was initialized.

analog input section of the board was initialized.

driver was configured for EXPs. Either reconfigure the
driver for no EXPs or avoid digital output operations.

Either the address select switches on the DAS-8 and
DAS-8PGA boards do not match the base address you
set when you configured the DAS-8 External DAS
Driver or the µCDAS-8PGA does not have a
programmed address equal to the configured base
address. Ensure that the base address in the
configuration file matches the board’s setting.

analog output section of the board was initialized.
An interrupt was generated before the program was

ready to handle it. This usually occurs when the
interrupt generator is running too fast.

14 Timer in use The internal clock is active and is not available for

another operation.

15 Interrupt A/D in use An interrupt A/D operation is running; no other A/D

operations can be performed until the interrupt A/D
operation is complete.

16 Interrupt D/A in use An interrupt D/A operation is running; no other D/A

operations can be performed until the interrupt D/A
operation is complete.

17 Interrupt digital input in

use

18 Interrupt digital output in

use

An interrupt digital input operation is running; no
other digital input operations can be performed until
the interrupt digital input operation is complete.

An interrupt digital output operation is running; no
other digital output operations can be performed until
the interrupt digital output operation is complete.

19