Measurement Micro488p User Manual

Micro488/p

the smart approach to instrumentation ™

IOtech, Inc.

25971 Cannon Road

Cleveland, OH 44146-1833

Phone: [phone]

Fax: [phone]

E-mail (Product Information): [e-mail]

E-mail (Technical Support): [e-mail]

Internet: www.iotech.com

User’s Manual

Micro488/p

User’s Manual

223-0901

p/n

© 1992 by IOtech, Inc. October 2002 Printing Revised per EO # 1634R1

Rev.

2.0

ii

Warranty Information

Your IOtech warranty is as stated on the product warranty card. You may contact IOtech by
phone, fax machine, or e-mail in regard to warranty-related issues.
Phone: [phone], fax: [phone], e-mail: [e-mail]

Limitation of Liability

IOtech, Inc. cannot be held liable for any damages resulting from the use or misuse of this product.

Copyright, Trademark, and Licensing Notice

All IOtech documentation, software, and hardware are copyright with all rights reserved. No part of
this product may be copied, reproduced or transmitted by any mechanical, photographic, electronic, or
other method without IOtech’s prior written consent. IOtech product names are trademarked; other
product names, as applicable, are trademarks of their respective holders. All supplied IOtech software
(including miscellaneous support files, drivers, and sample programs) may only be used on one
installation. You may make archival backup copies.

FCC Statement

IOtech devices emit radio frequency energy in levels compliant with Federal Communications
Commission rules (Part 15) for Class A devices. If necessary, refer to the FCC booklet How To
Identify and Resolve Radio-TV Interference Problems (stock # 004-000-00345-4) which is
available from the U.S. Government Printing Office, Washington, D.C. 20402.

CE Notice

Many IOtech products carry the CE marker indicating they comply with the safety and emissions
standards of the European Community. As applicable, we ship these products with a Declaration
of Conformity stating which specifications and operating conditions apply.

Warnings, Cautions, Notes, and Tips

Refer all service to qualified personnel. This caution symbol warns of possible personal injury or
equipment damage under noted conditions. Follow all safety standards of professional practice and
the recommendations in this manual. Using this equipment in ways other than described in this
manual can present serious safety hazards or cause equipment damage.

This ESD caution symbol urges proper handling of equipment or components sensitive to damage
from electrostatic discharge. Proper handling guidelines include the use of grounded anti-static
mats and wrist straps, ESD-protective bags and cartons, and related procedures.

Specifications and Calibration

Specifications are subject to change without notice. Significant changes will be addressed in an
addendum or revision to the manual. As applicable, IOtech calibrates its hardware to published
specifications. Periodic hardware calibration is not covered under the warranty and must be
performed by qualified personnel as specified in this manual. Improper calibration procedures may
void the warranty.

Quality Notice

IOtech has maintained ISO 9001 certification since 1996. Prior to shipment, we thoroughly test
our products and review our documentation to assure the highest quality in all aspects. In a spirit
of continuous improvement, IOtech welcomes your suggestions.

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iv

Contents

1 Introduction

1.1 Description …… 1-1

1.2 Available Accessories …… 1-1

1.3 Specifications …… 1-2

1.4 Abbreviations …… 1-3

2 Getting Started

2.1 Inspection …… 2-1

2.2 Serial Coonfiguration …… 2-1

2.3 Serial Signal Descriptions …… 2-2

2.4 Serial Cable Wiring …… 2-4

2.5 Hardware Installation …… 2-4

2.6 Is Anyone Out There? …… 2-5

2.7 Programming the Micro488/p …… 2-5

3 Command Descriptions

3.1 Introduction…… 3-1

3.2 Command Description Format …… 3-2

3.3 The Commands …… 3-5

Appendices

A – Micro488/p Command Summary
B – Character Codes and IEEE Multiline Messages
C – Sample Initialiazation Program

Micro488/p, Contents

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09-26-02

Micro488/p

Introduction

1.1 Description

The Micro488/p Bus Controller converts a host RS-232 computer into an IEEE 488
bus talker, listener, and controller. It provides the basic IEEE 488-1978 bus
implementation required for a system controller. The Micro488/p may be located up
to fifty feet from the host and may control as many as eight IEEE 488 bus
instruments.

The Micro488/p interprets simple high level commands sent from the computer's
serial port and performs the necessary, and usually complex, bus control and
handshaking. The commands and protocol are similar to those used by the Hewlett
Packard HP-85 computer.

1.2 Available Accessories

Available accessories for the Micro488/p include:

CA-7-1 1.5 foot IEEE 488 Cable.

CA-7-2 6 foot IEEE 488 Cable.

CA-7-3 6 foot shielded IEEE 488 Cable.

CA-7-4 6 foot reverse entry IEEE 488 Cable.

CA-35 Cable Set; includes one IBM PC/XT/PS2 to Micro488/p RS-232

Cable and one IBM AT to Micro488/p RS-232 Cable.

CN-20 Right Angle IEEE 488 adapter, male and female.

CN-22 IEEE 488 Multi-tap bus strip, four female connectors in parallel.

CN-23 IEEE 488 panel mount feed-through connector, male and female.

ABC488 IEEE 488 ABC switch.

Micro488/p, Introduction

09-26-02

1-1

1.3 Specifications

IEEE 488-1978

Implementation: C1, C2, C3, C4 and C28 controller subsets.

Terminators: Selectable CR, LF, LF-CR and CR-LF with EOI.

Connector: Standard IEEE 488 connector with metric studs.

Serial Interface

EIA RS-232C: AB, BA, BB, CA, CB.

Character Set: Asynchronous bit serial.

Output Voltage: 5 volts min. (RS-232C).

Input Voltage: 3 volts min.; 15v max.

Baud Rate: Selectable 300, 1200, 2400, 4800, 9600, and 19200.

Data Format: 8 data bits; 1 or 2 stop bits, no parity.

Duplex: Full with Echo/No Echo.

Serial Control: Selectable CTS/RTS or XON/XOFF.

Terminators: Selectable CR, LF, LF-CR and CR-LF.

Connector: 25-pin Sub-D male. RS-232C DCE Configured.

General

Data Buffer: 120 character input buffer.

Power: Draws less than 5mA from the DTR or DSR serial lines on the

host computer.

Max. Dimensions: 50mm x 60mm x 25mm (2" x 2.3" x 0.9").

Weight: 51.2 grams (1.8 oz).

Environment: 0° to 50°C; 0 to 90% R.H. non-condensing.

Controls: All settings auto or software configurable.

Note: Specifications subject to change without notice.

1-2

09-26-02

Micro488/p, Introduction

1.4 Abbreviations

The following IEEE 488 abbreviations are used throughout this
manual:

addr n IEEE bus address "n"

ATN Attention line

CR Carriage Return

data Data String

DCL Device Clear

GET Group Execute Trigger

GTL Go To Local

LAG Listen Address Group

LF Line Feed

LLO Local Lock Out

MLA My Listen Address

MTA My Talk Address

REN Remote Enable

SDC Selected Device Clear

SPD Serial Poll Disable

SPE Serial Poll Enable

SRQ Service Request

TA Talker Active

TAD Talker Address

term Terminator

UNL Unlisten

UNT Untalk

* Unasserted

Micro488/p, Introduction

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1-3

Notes:

1-4

09-26-02

Micro488/p, Introduction

Getting Started

2.1 Inspection

The Micro488/p was carefully inspected, both mechanically and electrically, prior to
shipment. When you receive the interface, carefully unpack all items from the
shipping carton and check for any obvious signs of physical damage which may
have occurred during shipment. Immediately report any such damage found to the
shipping agent. Remember to retain all shipping materials in the event that shipment
back to the factory becomes necessary.

Every Micro488/p is shipped with the following....

• Micro488/p IEEE488 Bus Controller

• Micro488/p User’s Manual, p/n 232-0901

2.2 Serial Configuration

Some of the Micro488/p serial communication parameters are pre-configured, and
can not be changed. The following list describes the parameters which are fixed
and, therefore, can not be changed:

Parameter Setting

Data Bits 8 Bit ASCII
Stop Bits 1 or 2
Parity None
Receive Terminator CR

The rest of the parameters are configured through software, after power on.
The following is a list of the software-configurable parameters:

Parameter Setting

Baud Rate 300, 1200, 2400, 4800, 9600, 19200
Duplex Full with echo/no-echo
Transmit Terminator LF, CR, LF-CR, CR-LF
Handshaking XON/XOFF or CTS/RTS

Getting Started

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2-1

2.3 Serial Signal Descriptions

The Micro488/p serial connector is configured as DCE type equipment for
RS-232 communications. This means the Micro488/p always transmits data on
Pin 3 and always receives data on Pin 2.

Note that the Micro488/p is equipped with a standard DB-25S connector and
requires a standard DB-25P mating connector.

Refer to the following figure and table to understand the relationship of the
Micro488/p connector’s pins and the associated RS-232 signals. Section 2.4 of
this document includes wiring information for making your own cables.

Micro488p Serial Connector Pinout

The following table idetifies the above connector pins in regard to
signal name and I/O type.

2-2

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Getting Started

Micro/488p Serial Connection

Pin Signal Name I/O Function

2RxD

Receive Data

Input

Accepts serial data sent by the RS-232 host.
The signal level is low true.

3TxD

Transmit Data

4CTS

Clear To Send

5RTS

Request To Send

6DSR

Data Set Ready

7Gnd

Ground

8DCD

Data Carrier Detect

Output

Input

Output

Input

N/A

Output

Transmits serial data to the RS-232 host.
The signal level is low true.

The CTS input is used as a hardware handshake
line to prevent the Micro488/p from transmitting
serial data when the RS-232 host is not ready to
accept it.

When RTS/CTS handshake is selected, the
Micro488/p will not transmit data out TxD while
this line is un-asserted (low).

If XON/XOFF handshake is selected, the CTS
line is not tested to determine if it can transmit
data.

The RTS output is used as a hardware
handshake line to prevent the RS-232 host from
transmitting serial data if the Micro488/p is not
ready to accept it.

This pin is used to provide power for the
Micro488/p if the DTR pin is in its false (LOW)
state, this pin must be in its true (HIGH) state in
order for the Micro488/p to operate properly.

This pin sets the ground reference point for
the other RS-232 inputs and outputs.

The function of this pin is similar to the CTS pin.
This pin is tied internally to its true (HIGH) state.

20 DTR

DataTerminal Ready

Getting Started

Input

Used to provide power for the Micro488/p when
the DSR pin (pin 6) is in its false (LOW) state.
Note that the DTR pin (pin 20) must be in its
true (HIGH) state in order for the Micro488/p to
operate properly.

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2-3

2.4 Serial Cable Wiring

If a cable was not purchased with the interface, the following diagrams will be helpful
in making your own cable. Simple soldering skills and attention to detail will ensure
successful construction.

IBM PC/XT/PS2 to Micro488/p IBM AT to Micro488/p

DB25,

Female

TXD 2 2 TXD DCD 1 8 DCD

RXD 3 3 RXD RXD 2 3 RXD

RTS 4 4 RTS TXD 3 2 TXD

CTS 5 5 CTS DTR 4 20 DTR

DSR 6 6 DSR GND 5 7 GND

GND 7 7 GND DSR 6 6 DSR

DCD 8 8 DCD RTS 7 4 RTS

DTR 20 20 DTR CTS 8 5 CTS

Two Scenarios for Making an Interface Cable (RS-232)

2.5 Hardware Installation

Installation of the Micro488/p consists of plugging the device into an available serial
port on the host computer.

DB25,

Male

DB9,

Female

DB25,

Male

2-4

09-26-02

Getting Started