Keithley KM-488-ROM User Manual

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KM=4881ROM

Keithley Data Acquisition

KeitNey MetraByte/Asyst

FCC Class B Compliance

NOTE: This equipment has been tested

and

found to comply with the limits for a Class B Digital Device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does not cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

Reorient or relocate the receiving antenna.

Increase the separation between the equipment and receiver.

Connect the equipment into

outlet on a circuit different from that to which the receiver

is connected.

Consult the dealer or an experienced radio/tv technician for help.

NOTE:

The use of a non-shielded interface cable with the referenced device is prohibited.

User Guide

for the

KM-488-ROM

IEEE-488 Interface

Board

R~vislon A

- March $99,

Copyrlghl

Kelthley Data AC ulsltlon 1991

a Part Number: 244 9

KElTHLEY DATA ACQUISITION - Kelthley MetraSytelAsyst

440 Myles Standish Blvd., Taunton, MA 02790

TEL. 609/99%?0W. FAX MW990-0179

- 11, -

warranty Information

All products manufactured by Keithley Data Acquisition are warranted against defective materials and worksmanship for a period of one year from the date of delivery to the original purchaser. Any product that is found to be defective within the warranty period will, at the option of the manufacturer, be repaired or replaced. This warranty does not apply

to products damaged by improper use.

warning

Keithley Data Acquisition assumes no liability for damages

consequent 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.

Disclaimer

Information furnished by Keithley Data Acquisition is believed to be accurate and reliable. However, Keithley Data Acquisition assumes no responsibility for the use of such information 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 Keithley Data Acquisition.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form by any means, electronic, mechanical, photoreproductive, recording, or otherwise without the express prior written permission of the Keithley Data Acquisition.

Note:

Keithley MetraByteW is a trademark of Keithley Instruments.

Basi? is a trademark of Dartmouth College.

IBM@ is a registered trademark of International Business Machines Corporation.

PC, XT, AT, PS/Z, and Micro Channel Architecture@ are trademarks of International Business Machines Corporation.

Microsoft@ is a registered trademark of Microsoft Corporation. Turbo C@ is a registered trademark of Borland International.

- iv -

Contents

CHAPTER 1

- INTRODUCTION

1.1

1.2

1.3

1.4

Overview

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

.1-l

Specifications

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

1 1 1 1

.I-2

Ordering Information

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

. l-3

HowToUseThisManual..

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

.l-3

CHAPTER 2 - INSTALLATION

2.1

2.2

2.3

2.4

2.5

2.6

2.7

2.6

General

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

Unpacking & Inspecting

.2-i

Software Installation . 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 . ’

. .2-l

.2-l

Switches 3 Jumpers

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

: : : : .2-2

Board Installation

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

Configuration Of The EEPROM

.2-7

Reloading The

EEPROM

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

: : : : : : : : : : : : : : : :

.. .2-a

2-10

Multiple Board Installation Notes

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

2-10

CHAPTER 3 -

INTRODUCTION TO CALLABLE ROUTINES

3.1

3.2

3.3

3.4

3.5

3.6

3.7

3.6

3.9

Initializing The KM-486-ROM.

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

.3-3

Selecting The Receive & Transmit Terminators Transmitting Commands&Data.

...........

: : : : : : : : : : : : : : : :

.. .3-3

.3-5

Reading Data

.....

...

Transmitting/Receiving Data Via

DMA

................. : : : : : : : : : : : : : : : :

3-11 3-14

Checking Device Status

3-15

Low-Level Routines.

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

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

3-17

Board Configuration

Routines

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

3-16

Multiple Board Programming Notes

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

3-19

CHAPTER4 -

PROGRAMMING IN BASICA OR GWBASIC

4.1

4.2

4.3

General

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

.4-i

Description Format For Routines.

.4-3

Routines.

....

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

: : : : : : : : : : : : : : : :

.4-3

CHAPTER 5 - PROGRAMMING IN QUICKBASIC

5.1

5.2

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-i

5.3

Description Format For Routines. . . . . . . . . . . . . . . . . . .5-3

Routines. . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3

CHAPTER 6 - PROGRAMMING IN TURBO PASCAL

6.1

6.2

6.3

General . . . . . . . . . , . . . , . . . . . . . . . . . . . . . . . . . . . .6-l

Description Format For Routines. . . . . .

Routines. . . . . . . . . . . . . . . . : : : : : : : : : : : : : : : : : ’

. .6-2

. .

6-3

Contents

CHAPTER 7 - PROGRAMMING IN C

7.1

General.

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

7-l

7.2

Description Format For Routines ...........................

7-3

7.3

Routines

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

7-3

CHAPTER6 - FACTORYRETURNS

APPENDICES

Appendix A - ASCII Code Chart Appendix B - IEEE Tutorial Appendix C - IEEE Multiline Commands Appendix D - Device Capability Codes Appendix E - Printer & Serial Port Redirection

n DD

- vi -

Chapter 1

INTRODUCTION

1.1 OVERVIEW

The KM4?8-ROM is an IEEE488 interface board that allows programs written on IBM PC/XT/ATs, IBM I’S2 25/3Os, or compatibles

to communicate

with an IEEE488 bus. This Board complies with the 1978 IEEE488 standard and is thus compatible with other IEEE488 products. Up to fourteen other devices may be connected to the IEEE488 bus, including instruments, printers, and other computers. The KM48-ROM

comprises a board,

software,

and documentation. Figure l-l is a block diagram of the KM-488-ROM board.

Figure l-l. KM-4&WROh4 Block Dlagram

The Kh4488-ROM design includes a Wait State Generator to adjust bus timing, allowing performance within operating specifications of the GLIB controller chip on the fastest PCs. This Board can also generate programmed interrupts on any of six interrupt request lines and DMA transfers on Channels 1,2, and 3. Selection of message terminators and timeouts is modifiable to allow communication with GPIB devices using non-standard characters and

timeouts.

INTRODUCTION 1 - 1

1.2

The KM-488-ROM also features an 8-KB EEPROM (Electrically Erasable Programmable Read Only Memory) containing firmware routines callable from a BASICA program. These routines perform the IEEE-488 transfer functions. KM-488ROM software libraries allow access to routines from programs in QuickBASIC, Microsoft C, and TURBO PASCAL. Examples for each language are included.

SPECIFICATIONS

Dimensions:

DMA Level:

Interrupt URQ) Capability:

Data Transfer Rate (Governed by the

slowest device):

IEEE Controller Chip:

Power Consumption:

Operating Temperature:

Storage Temperature:

Humidity:

Wait States:

Net Weight:

ROM Base Address:

I/O Base Address:

Device Interface Capabilities

Supported:

One Short PC Slot size. Channels 1,2,3, or None (Jumper Selectable). Levels 2 through 7 or None (Jumper Selectable).

> 300 Kb per second.

NEC7210.

< 500 mAmps.

0 to 50 T.

-4 to 158 ‘F (-20 to +70 “0. 0 to 90% noncondensing. 1,2,3, or 4 (Switch Selectable).

.31

lb (.14 kg). Switch Selectable. Switch Selectable. SHl, AHI, T5, TE5, L.3, LE3, SRl, RLl, PPl, PP2,

DCl, DTl, Cl-5, E1/2. (See Appendix D for clarification.)

1-2 KM-488~ROM USER GUIDE

1.3 ORDERING INFORMATION

PARTNUMBER

DESCRIPTION

KM-488-ROM Includes the KM-488-ROM IEEE-488 Interface Board,

Software (on 5.25” disks), and appropriate documentation.

KM-488-ROM/3.5 Includes the KM-488-ROM IEEE488 Interface Board,

Software (on 3.5” disks), and appropriate documentation.

CGPIB-I 1 meter IEEE-488 cable. CGPIB-2 2 meter IEEE-488 cable. CGPIB-4 4 meter IEEE-488 cable.

1.4 HOW TO USE THIS MANUAL

This manual provides the information necessary to install and program the KM-488-ROM. The manual assumes you are familiar with the language in which you are developing your application program; it also assumes you are familiar with the IEEE-488 protocol.

Chapter 2, Installation, details how to unpack, inspect, configure, and install the KM-488 ROM and how to copy the accompanying software. Additionally, Chapter 2 describes how to install the KM48EROM software and to configure the EEPROM and reload EEPROM

software. There are also notes on using multiple boards in one system.

Chapter 3, Zntroductfan fo the

CaRable Routines,

provides a brief functional description of each

KM488-ROM Interface Routine. Chapter 4, Programming the

KM-488-ROM,

provides a detailed description of each KM-488-

ROM Interface Routine and how it is called from each of the supported languages:

BASICA,

QuickBASIC, C, and TURBO PASCAL. Chapter 5, Factory Returns , gives instructions for returning the board to the factory. The appendices contain additional useful information. Appendix A contains an ASCII

Equivalence Chart. This gives hex and

decimal

equivalents for the ASCII 128 Character set. Appendix B is an IEEE-488 tutorial. Appendix C provides an explanation of the Device Capability Identification codes. Appendix D provides a cross-reference chart of IEEE Multiline Commands. Appendix E describes how to use the KM488-DD Printer Port Redirector.

INTRODUCTION 1 - 3

l-4 KM-488-ROM USER GUIDE

Chapter 2

INSTALLATION

2.1 GENERAL

Installation begins with procedures for unpacking and inspection followed by recommendations and instructions for software. Next is a section on switch and jumper

settings. Board installation is the next step, followed by EEPROM configuration.

2.2 UNPACKING 81 INSPECTING

After removing the wrapped Board from its outer shipping carton, proceed as follows:

1. Before unwrapping the Board, place one hand firmly on a bare-metal portion of the computer chassis to discharge static electricity from yourself and the Board (the computer must be turned Off but grounded).

2. Carefully remove the Board fromits anti-static wrapping material. You may wish to save the wrapping material for possible future use; if so, store it in a safe place.

3. Inspect the Board for signs of damage. If any damage is apparent, return the Board to the factory.

4. Check the remaining contents of your package against the packing list to be sure your order is complete. Report any missing items to the factory immediately.

5. When you are satisfied with preliminary inspection, you are ready to configure the Board. Refer to the next section for configuration options.

2.3 SOFTWARE INSTALLATION

Backing Up The Distribution Software

As soon as possible, make a back-up copy of your Distribution Software. With one (or more,as needed) formatted diskettes on hand, place your Distribution Sofhvare diskette in

your PC’s A Drive and log to that drive by typing A: . Then, make your backup using the

DOS

COPY

DISKCOPY

command, as described in your DOS reference manual

(DISKCOPY is preferred because it copies diskette identification, too).

installing The Distribution Software

Install the KM-488-ROM Distribution Software on your computer’s hard drive using the DOS COPY command.

INSTALLATION 2 - 1

NOTE: If you are using BASICA and the factory default settings, you may run the KM-

4%ROM board without installing any software. Instead, proceed to Section 2.4.

To install the software:

1. Turn on your PC and its display. You should see the standard DOS-level prompt. NOTE: If you install example programs written in multiple languages, you may want to

create a directory for each language. (This is the way the Distribution Software is organized.)

2. The following instructions create a directory named

KM488R. Type md \Rld488R

3. Change to the KM488Rdirectory by typing cd \KM488R

4. Place a KM-4&%ROM Diskette into the floppy drive (assume this is Drive a:) and type copy a:*.*

Repeat this step for each disk and/or subdirectory, until copying is complete.

Distribution Software Contents

Your Distribution Software contains the file

FILESDOC

, an ASCII text file readable with any

text editor or with the DO!?

TYPE

command. FlLES.DOC lists and briefly describes all files

in the Distribution Software.

The README.DOC File

To learn of last-minute changes, be sure to read the ASCII file

READMEDOC

2.4 SWITCHES & JUMPERS

Factory Settings

The KMG%-ROM contains three DIP switches and two jumper banks (see Figure 2-l). These switches and jumpers are factory-configured to work with most PC configurations. Table 2-l lists the factory selections.

Table 2-1. Factory Switch & Jumper Settlngs

SWITCH/JUMPER

FACTORY SE’ITING

I/O Base Address: 2b8h.

ROM Base Address: CCOOh ROM Enabled.

I/O Wait State:

1 Wait State; System Controller Enabled; EEPROM

Write Disabled.

Interrupt (IRQ) Level: Disabled.

DMA Level: Disabled.

2-2 KM-488~ROM USER GUIDE

For assistance with setting the switches or the jumpers, run the INSTALL program. This program illustrates the correct switch settings for your selections. To run the INSTALL program, make sure you are in the appropriate directory and type INSTALL at the DOS prompt. Then, follow program directions.

Figure 2-1. Switch and Jumper Locatlons

Switches

There are three DIP switch blocks on the KM48-ROM board, as follows: Wait State (Sl), I/O Base Address (S2), and ROM Base Address 63). The switches are factory-set to work with most PC configurations (see Table 2-l for settings).

NOTE: If you are using BASICA and change the I/O Base Address DIP switch settings, be

sure to run the configuration program, CONFIG. See Section 2.7.

I/O Base Address Switch

Setting an I/O Base Address enables the KM-488-ROM to communicate with the PC. You set an I/O Base Address for the Board by setting the seven positions of Switch S2 for the assigned address. Setting a switch position to ON puts the corresponding address line at a logic 0 (low).

The KM-488-ROM requires a series of 8 I/O port addresses that begin with the I/O Base Address. Therefore, be sure to select an I/O Base Address on an B-byte boundary that does not conflict with other devices in your computer (refer to your PC manual for the I/O address list to determine available spaces).

Figure 2-2 shows examples of I/O Base Address settings. Note that the factory-set Base Address is 288 hex; the I/O ports occupy the address range 288 - 2Bf Hex.

INSTALLATION

2-3

FIgore 2-2. Examples of l/O Base Address SeftlngS

ROM Base Address Switch

This switch determines whether the ROM memory is to be enabled and, if so, where within the first 1 MB of PC memory it is to be located. Enable the ROM if you are programming in BASICA. The ROM Base Address Switch 63) is an B-position DIP switch.

Seven of the S3 positions (1 - 7) to select the ROM Base Address. Position 8 enables/disables the ROM. Setting a position at ON puts the corresponding address line to a logic 0.

To enable or disable the ROM, set 53 Position 8 as shown in Figure 2-3. This position should be ON only if the KM-W-ROM is used with BASICA software.

Flgure 2-3. Enabllng the ROM ~%B,EO %&LED

Some alternative ROM Base Address switch settings are shown in Figure 2-1. The default

Base Address is CC00 hex. Be sure to select an 8 KB address space that is within the first 1 MB of PC memory and not occupied.

Flgure 2-4. ROM Base Address Selectlon

If you are

unsure

which address to assign to the EEPROM, use the MEMMAP program provided with the KM-488-ROM. This program scans your computer’s memory and determines what memory areas are available. To invoke the MEMMAI’ program, switch to the appropriate directory and type

m . Choose an unoccupied address space.

2-4 KM-488-ROM USER GUIDE

Wait State Switch

Switch 1 (Sll configures Wait States and the System Controller

ON = 0

Mode, and it enables Memory Write Protection. Sl is a 4-position DIP switch (see Figure 2-5). Setting a position to ON puts the corresponding address line at signal low (logical 01. Two positions (1 and 21 select the wait states.

Flgure 2-5. Welt State Switch.

Configure the System Controller function using Position 3 and the EEPROM protection using Position 4.

I/O Waif States

The KM-B&ROM design includes a switch-selectable wait-state generator. A selectable Wait State insures optimum performance and reliable operation at the differing bus clocks found in PCs. The default number of Wait States (11 should be correct for most PCs. vowever, if,youf data is garbled or your program crashes, you may need to adjust

the number of Wait States. Some general guidelines are presented in Table 2-2. Select the number of Wait States by setting Positions 1 and 2 (marked Wait State) on the DIP switch. You may program

‘03 911’1

, w*,, STATE , w*l, STITFS

the KM468-ROM to generate one, two, three, or four Wait States

during

I/O. Note that the number of memory Wait States is automatically set to a value which is one less than the I/O Wait States. To select a number other than the default, set the switches to one of the positions shown in Figure 2-6.

iE~Yg~

2 WNT sTME9 4 WIT STATES

Figure 2-6. t/O

Walt

State Seiectlons

Table 2-2. Welt States

BUS CLOCK FREQUENCY NUMBER OF WAIT STATES

<=5MHz

1 (default).

5MHz <ticq <8MHz

8MHz <freq < 10MHz

10 MHz < freq

System Controller

This switch determines whether or not the KM488-ROM will act as a System Controller. If the KM-488-ROM is a System Controller, it has the ability to assert the IFC or REN lines.

Position 3 cm the Wait State DIP Switch determines whether

3 ON

the KM-438-ROM is acting as a Device/Controller or a System Controller. Valid selections are shown in Figure 2-7.

ON i

ON = 1

Figure 2-7. Device Mode Selection

II 1’

DEVICE OR SYSTEM CONTROLLER

CONTROLLER

INSTALLATION 2 - 5

Memory Write Enable

Positlone 4 on the Wait State DIP Switch enables or disables writes to the EEPROM on the KM488-ROM. Valid selections are shown in Figure 2-8.

Flgure2-8. EEPROM Enable Selection

EEPROM WR,TE

EEPROM WRITE

ENABLED

DlSABLED

This switch should normally be at DISABLE. It should be at ENABLED only when initializing or configuring the EEPROM BASICA support software.

Jumpers

The KM-ltlE-ROM contains two jumper blocks. These blocks select the Interrupt Level and

DMA Level.

Selecting an Interrupt Level

The KM-@&ROM is capable of interrupting the PC. The Interrupt Level (IRQ) Jumper (Jll defines the Interrupt Level. Valid Interrupt Level selections (2 through 7 and none) and the jumper positions are shown in Figure 2-9.

Figure 2-9. Interrupt Level (Ml) Jumpers

Selecting a DMA Level

DMA (Direct Memory Access) is a PC facility for speeding up data transfer from a peripheral to the computer. Select an appropriate DMA level using the DMA Level Jumpers. Refer to

2-6

KM-488-ROM USER GUIDE

Figure 2-10 for jumper positions.

F/gum 2-10. DMA Level Jumpers

2.5 BOARD INSTALLATION

To install the KM-488-ROM in a PC, proceed as follows:

1. Turn Off power to the PC and all attached equipment. WARNING!

ANY ATTEMPT TO INSERT OR REMOVE ANY ADAPTER BOARD WITH COMPUTER POWER ON COULD DAMAGE YOUR COMPUTER!

2. Remove the cover of the PC.

3. Choose an available option slot. Loosen and remove the retainer screw at the top of the blank adapter plate. Then slide the plate up and out to remove.

4. Before touching the Board, place one hand on any metallic part of the PC chassis (but not on any components) to discharge any static electricity from your body.

5. Make sure the Board switches have been properly set (refer to the configuration sections).

6. Align the Board connector with the desired accessory slot and with the corresponding rear-panel slot. Gently press the Board into the socket and secure with the retainer screw

for the rear-panel adapter-plate.

7. Replace the computer cover.

8. Plug in all cords and cables. Turn the power to the computer back on. You are now ready to make any necessary system connections.

INSTALLATION 2 - 7

If you are developing KM488-ROM application programs in C, TURBO PASCAL or QuickBASIC, the installation process is now complete. However, if you are developing programs in BASICA and have changed the factory default settings, you must to run the

EEI’ROM configuration program CONFIG.

2.6

CONFIGURATION OF THE EEPROM

When KM488-ROM application programs use BASICA, the programs read interface functions directly from the on-board EEPROM. Thus, the EEPROM must be properly configured, which may be accomplished using the CONFIG program. This program allows you to change such parameters of the EEPROM configuration as I/O Base Address, l/O Timeout, DMA Timeout, and Transmit/Receive Terminators.

Before changing the EEPROM configuration, you may want to read the descriptions of the DMA, RCV, and XMIT routines in Chapter 3. Also make sure that the ROM Base Address switch has the ROM Write function enabled. (See Section 2.4.)

Invoking The CONFIG Program

Invoke the CONFIG program as follows:

1. Install the Distribution Software (see Section 2.3) and the KM488-ROM board (see Section

2.5).

2. Switch to the appropriate directory. At the DOS prompt, type CONFIG

The PC monitor will show a screen labelled

K&-488-ROM CONFIGURATION. The

settings

will reflect any changes which were made by running the INSTALL program.

The following PC function keys are now active:

[E-II

[ml

[F31

I Shift II F3 I

[AltI[F31

[F81

HELP Invoke Help at any time by pressing [ Fl ] SHOW NEXT. In multiple board systems, pressing [ Fl I shows the

configuration of the next KM488-ROM. LOAD . Pressing this key loads the file KM488ROM.BlN to the EEPROM.

This function is useful when you want to load the factory defaults back into the KM488-ROM’s EEPROM.

LOAD NEW MEMORY. Pressing this key combination allows you to load the contents of the KM488-ROM’S EEPROM to a new segment of

DOS memory. The value you enter here must agree with the address selected by the ROM Base Address Switch. If you have trouble identifying

an unoccupied space, run the MEMMAP program (see Section 2.4). EDIT I/O ADDRESS. This key combination permits you to edit the I/O

Address field only. This

the address for access to the KM488-ROM. It

is important that you select an l/O Base Address on an S-byte boundary

that

does not conflict with other devices in your computer. The I/O Base

Address must fall within the range 200h to 3F8h. EDIT. This key allows editing of the configuration parameters (see the

next section for parameter descriptions). When editing is complete, press 1 MO 1. When the prompt Save changes to KM-488-ROM memory? Y/N appears, enter the appropriate response.

2-8 KM-488-ROM USER GUIDE

[ FlO I EXIT. Pressing this key exits the editing process. Otherwise, pressing

[ FlO I exits to the DOS prompt.

Once you have completed writing to the EEPROM, be sure to disable the EEPROM Write function (see Section 2.4).

NmEz Be sure to reset the EEPROM Write Switch when you complete writing to the

EEI’ROM. Many software programs are designed to search for free address space within the computer and may interpret the EEPROM as such.

Editing The Configuration Parameter Fields

Once you have invoked the EDIT function, you will be able to edit the configuration parameters. To exit from the EDIT function at any time, press I FlO

To move between fields, use [ ? I and [ J I . Once you make your selection for a given parameter, press [ Enter 1 These parameters include the following:

DMA Timeout

I/O Timeout If the time elapsed between the transfer of individual bytes

exceeds the specified I/O Timeout period, an I/O Timeout Error will occur. This parameter sets the maximum amount of time (in milliseconds) which is to elapse. Enter a value between 0 and 65535 milliseconds for the I/O timeout. The default value is 10010 Ins.

A DMA Timeout Error is generated when the time to transfer (via DMA) an entire message exceeds the set DMA Timeout value. Valid entries for the DMA Timeout parameter are between 0 and 65535 milliseconds. ‘Ihe default value is 10010 Ins.

Transmit Terminators

Transmit Terminators (also referred to as Output Terminators) are appended to data sent from the KM-488-ROM to another IEEE-488 device. The terminators signal the end of the data transfer. The Transmit Terminator sequence consists of one or two ASCII characters with EOI optionally asserted, when the last terminator character is sent. Up to four different Transmit Terminator sequences may be selected.

To select a terminator sequence,

1. Referring to the ASCII Equivalence Chart in Appendix A, enter the HEX VALUE @Oh - FFh) of the first terminator byte. Press [ Enter I .

2. Repeat Step 1 for the second terminator byte. If a second terminator byte is not required, enter spaces. Press [ Enter ] .

3. Press 1 Space Bar 1 to enable EOI(EO1) or disable EOI (NOEOI). Press [ Enter I .

Repeat these three steps for each of the remaining Transmit Terminator Sequences.

The default Transmit Terminator Sequences are as follows: Terminator 0

LF EOI Terminator 1 CR LF EOI Terminator 2

CR EOI Terminator 3

LF CR EOI

INSTALLATION

2 - 9

Receive Terminators The KM488-ROM uses these items (also referred to as Input

Terminators.) to detect the end of a data transfer received from another device. The Receive Terminator sequence consists of one ASCII character with EOI optionally asserted. If the chosen

terminator character is detected in the incoming data, reception

will terminate. Note that any data byte received with EOI asserted will always terminate reception, regardless of the

selected terminator. Up to four different Receive Terminator sequences are available

for selection, as follows: Terminator 0

LF EOI

Terminator I

CR EOI

Terminator 2 , (comma) EOI

Terminator 3

; (semi-colon) EOI

To change the terminator character, use the procedure

previously outlined for Transmit Terminators.

2.7 RELOADING THE EEPROM

Under some conditions (for example, if the EEPROM contents have been destroyed), you will have to reload the EEPROM with the contents of the Kh4488ROM.BIN file. To perform this requirement, run the CONFIG program, as described in the previous section.

Before you reload the EEPROM, be sure its Write/Enable switch is enabled (see Section 2.4). The proceed as follows:

1. Invoke the CONFIG program. Switch to the appropriate directory and at the DOS prompt, type CONFIG.

2. Press [ F3 I.

When you completed the EEPROM reload, be sure to disable the EEPROM Write Enable switch (see Section 2.4).

2.8 MULTIPLE BOARD INSTALLATION NOTES

The KM-483-ROM software allows installation of up to four boards in a given system. Typically, situations with excessive cable lengths or more than 14 instruments require multiple boards.

When using multiple Kh4-488-ROMs, set the I/O Port Base Address to a different value on each of the boards. Routines within the software library allow you to determine which board to use by specifying the Base Address of the I/O port on that board.

When using BASICA, each board requires its own copy of software.

This means that you must select a different EEI’ROM memory address and I/O Base Address for each board. These Base Address ranges CANNOT overlap other address ranges within the system.

2-10

KM-4WROM USER GUIDE

Chapter 3

INTRODUCTION TO CALLABLE ROUTINES

To use the KM488-ROM within a custom data acquisition or control environment, you have to write software that will access the GPIB. The KM488-ROM includes a number of “callable” routines allowing this access from high-level languages such as BASIC, Quick BASIC, C, and TURBO PASCAL.

This chapter describes the callable-interface routines from a functional approach. Chapter 4

provides the exact syntax for calling the routine from BASIC, Quick BASIC, C, and TURBO PASCAL. Table 3-l provides an alphabetical listing of the available routines. The remainder of the chapter tracks the order of a routine’s usage and is organized as follows:

Initializing the KM488-ROM.

. Selecting the Receive and Transmit Message Terminators.

Transmitting Commands and Data.

Reading Data.

Transmitting/Receiving Data via DMA.

Checking the Status of a Device.

Low-level Routines.

Configuring the Board.

NOTE:

Explanations within this chapter assume you are familiar with IEEE486 communications. If you are new to IEEE488 or do not recognize some of the terminology used, refer to the IEEE488 Tutorial in Appendix B.

INTRODUCTION TO CALLABLE ROUTINES

3-1

Table 3-1. The Callable RoutlnSS

ROUTINE NAME

DESCRIPTION

GPIB OPERATIONS

DMA

DMATIMEOUT ’

ENTER

INIT

INTERM ’

IOTIMEOUT 1

OUTTERM ’

PPOLL

RCV

RCVA

SEND

SETBOARD 2

SETDMA 2

SETINT

SETPORT 2

SETSPOLL

SPOLL

SRQ 2

STATUS

XMIT

XMITA

Used to transmit/receive array data via DMA. (BASICA only) Sets maximum length of time for a DMA transfer. Addresses a device to talk and receives the talker’s data into a suillg. Initializes the KM-488-ROM.

Redefines input terminator settings. Sets the maximum length of time for an I/O transfer. Redefines output terminator settings. Performs a parallel poll.

Receives data into a string. Receives data into an array.

Addresses a specific device to listen and allows the current talker to send the data from a string.

Identifies, in a multiple board system, the board to be programmed. Allows use of DMA in conjunction

with XMITA and RCVA routines. Allows the KM-488~ROM interrupt enable bits to be set. Selects a non-default Base Address. Sets Serial Poll Response of the KM-488-ROM. Conducts a serial poll on a specified device.

Detects the state of tic SRQ signal on the bus.

Returns values of the various setup parameters.

Sends GPIB commands and data.

Transmits data from an array.

Asserts REN. Sends UNL, UNT, TALK adrs, MLA, data, UNJ-, LINT.

If KM-48%ROM is Sys. Contr.,

assert.9 IFC.

None.

Asserrs ATN and EOI and reads data byte.

Receives data. Receives data. Asserts RBN. Issues UNL, UNT, Listen Adrs, MTA, and sends data followed by a message terminator. None.

None. If RSV bit is set, will sssert SRQ.

Asserts REN. Issues UNL UNT, Talk adrs, SPE. Receives Serial Poll Response. Issues SPD. None.

Sends GPIB commands and data

as specified in string.

Sends data, optionally terminates

by EOI and/or terminator

characters

1 This routine is not supported in BASICA. To modify this parameter, use the

CONFIG program.

2 This call is not supported in BASICA. Its function, however, can be achieved

through different means.

3-2

KM-485ROM USER GUIDE

3.1 INITIALIZING THE KM-488-ROM

The first step in any KM488-ROM application program is to initialize the KM488-ROM board(s), using the lNIT routine.

3.2

INIT

This routine configures the KM4?8-ROM as a device or a controller. INIT also defines the Gl’IB address and determines whether Bus Handshaking is to be High or Low Speed. If INIT designates the KM-488-ROM as a System Controller, the Interface Clear (IF0 line on the GPIB

is asserted momentarily when INIT is called. Either High or Low Speed Handshaking is available. In High Speed mode, the KM-488~ROM

asserts the GPIB bus signal DAV approximately 500 ns after data is placed onto the bus. In the low speed mode, DAV is asserted about 2 microseconds after the data. In most cases, you will see no apparent differences in data throughput with Low Speed Handshaking. To maximize data throughput when using DMA, select High Speed Handshaking.

NOTE: Use the High Speed mode only in smaller installations, because High Speed

Handshake mode allows less time for data to settle. Thus, as cable lengths increase, the probability of transmission errors from cable reflections will increase.

NOTE: INIT must be the first KM-488-ROM routine called within the program.

lOTIMEOUT

This routine is not usable in BASICA. IOTIMEOUT allows you to reset the length of time that is to elapse before a Timeout Error occurs. A timeout Error occurs when the time between transmission and reception of adjacent bytes exceeds the set time. (I/O Timeout Error reports occur when using SEND, ENTER, XMITA, XMIT, and RCVA calls without DMAJ The default value of the timeout period is 10 seconds.

NOTE: The I/O Timeout may be changed at any point in the program.

SELECTING THE RECEIVE 81 TRANSMIT TERMINATORS

When data is transmitted to or from the KM-488-ROM, it may contain message terminator characters. These terminator characters are used to signal the end of data transmission.

Every KM-488-ROM routine that transmits or receives data contains a parameter allowing you

to define which of the default terminator sequences is to be used. If your application program is in C, QuickBASIC, or Turbo PASCAL, you may change the default terminator sequences by

calling the INTERM and OUTIERM routines. If you are programming in BASICA, you may change the default Transmit/Receive

Terminator sequences and the I/O Timeout period only by running the CONFIG program (see Sections 2.6 and 2.7).

INTRODUCTION TO CALLABLE ROUTINES

3 - 3

INTERM

This routine does not work in BASICA. INTERM allows you to change the values of each of

the four input message terminators. These terminators can be detected by the ENTER, RCV, and RCVA routines.

Each terminator sequence consists of one ASCII character (7-bit value). The default value for each terminator is shown below.

DECIMAL HEX

TERM # ASCII CHARACTER EQUIVALENT

EQUIVALENT

LF (Lime Feed) 10 OA 1 LF (Line Feed) 13 OD 2 , (comma) 44 2c 3 : (semi-colon) 59 3B

Note that if EOI is asserted withany data byte, data reception will be unconditionally terminated.

Instrument manufacturers frequently specify message terminators using ASCII representations. You may pass either the decimal or hexadecimal equivalents of the desired ASCII character into the INTERM routine. If using the hexadecimal value, be sure to use the correct prefix. This prefix is language-dependent. Check the language manual for more information.

OUTTERM

This routine does not work with BASICA. OUTTERM allows changes of values for each of the

four output message terminator sequences. You may append these terminators to the data sent by the SEND, XMIT, and XMITA routines to signal the end of message.

Each terminator sequence consists of one or two ASCII characters (irbit values) and may or may not assert EOI when the last terminator character is sent. The default values for each terminator appear in the following table.

ASCII CHARACTER DEC EQUIV

HEX EQUIV

TERM # IST ZND 1ST

2ND

1ST 2ND

EOI

0 LF 10 OA YES

1 CR LF 13 10 OD OA YES 2 CR 13 OD YES 3 LF CR 10 13 OA OD YES

Instrument manufacturers frequently specify message terminators using ASCII representations. You may pass either the decimal or hexadecimal equivalents of the desired ASCII character into the INTERM routine. For example, specify a Line Feed as OAh. If using the hexadecimal value, be certain to use the correct prefix; this prefix is language-dependent. Check the language manual for more information.

Terminators specified with this routine must be at least one character long. If you have an instrument or application requiring no terminator bytes (requiring assertion of EOI), use the XMIT or XMITA routine to transmit the data.

3-4

KM-488~ROM USER GUIDE

3.3

TRANSMllTlNG COMMANDS AND DATA

Once the GPIB system is initialized, the next step is usually to send commands and/or data to a device. Use any of the following routines to send:

SEND

XMIT

XMITA

IOTIMEOUT

SEND

Use this routine only when the KM488-ROM is an Active Controller.

SEND transfers string data from the KM488-ROM to the device specified by first addressing the KM488-ROM as a talker and the indicated device as a listener, and then asserting the REN line. Next, the command sends the string, followed by the selected message terminator, to the listener. The routine returns a status variable indicating whether or not the transfer is properly completed.

XMIT

The XMIT Routine allows the greatest amount of flexibility for sending GPIB commands (see Section 3.4.) and data. Data and commands to be sent over the GLIB are expressed in string form and then passed into the XMIT routine. All commands within the string may be UPPER or lower case; but they must be separated by one or more spaces.

If the KM488-ROM is acting as a Controller, the XMIT routine sends both commands and data. If executing the XMIT routine, the KM488-ROM must

Untalk and Unlisten all Devices.

Assign a Listener.

Address itself as a Talker.

If, however, the KM488-ROM is acting as a Device, the XMIT routine can only send data. In this instance, the KM488-ROM must be a talker before the XMIT routine can execute.

The XMIT routine will then parse the string and extract and send the commands over the bus in the specified sequence. The commands to carry out this sequence can all be within a single

string and handled by a single call to the XMIT routine.

The XMIT routine returns a single status variable to indicate the state of the data transfer. XMIT will report cases of invalid syntax, invalid address, undefined commands, timeout

errors, and attempts to send bus commands while not the active controller.

THE XMIT COMMANDS

Send these commands in the XMIT command’s info string; they consist of rudimentary GPIB and other commands and separate by function into three categories, as follows:

1. Data Transmission.

2. Polling.

3. Miscellaneous.

INTRODUCTION TO CALLABLE ROUTINES

3 - 5

DATA

END

EOI

GTL

Use this command after the KM-488-ROM has been addressed to talk. (If the KM-488-ROM is controller, issue an MTA. Otherwise, the Controller must address the KM-488-ROM. See the STATUS routine description for more information.) DATA sends the message that trails it to all previously addressed listeners.

Data may be in two forms. In one form, data is a string of ASCII characters that trails the DATA command. The ASCII string will be in single quotes (for example, ‘BYE’).

In the other form, data may be a string of numeric values, each of which ranges from 0 to 255. Each numeric value is the decimal equivalent of an ASCII character (see Appendix A for ASCII Equivalents). One or more spaces must separate each numeric entry. This form of entry is useful

where transmission of nonprintable characters is required. Note that you

may switch freely between the ASCII and Decimal representations after

the DATA command, as long as ASCII characters are in a string enclosed

by single quotes.

EXllmple

DATA ‘Eello’ 13 10 DATA

'Line

1’

10 ‘Line 2’ 13 10

If END follows the DATA command string, Message Terminator 0 signals the End of Transmission. Section 3.2 describes the default values of the transmit terminators and how to change them. Set the terminators to one or two bytes, and send them with or without EOI asserted on the last byte.

Example

DATA ‘Eello’ END If EOI (END OR IDENTIFY) follows the DATA command string, it

indicates that the character following EOI mnemonic will be sent with the

EOI line asserted.

Example

DATA ‘Hello’ 13 EOI 10

The GTL command forces bus devices addressed to listen to the Go To Local (front panel controllable) state, as opposed to controlled via Gl’lB. This command also onasserts the REN signal on the GPIB. Only the System Controller may use GTL. Note that this command DOES NOT allow you to selectively force only one device to Go To Local.

Note that it is more practical to use GTLA and LOC commands than GTL.

Example

GTL

3-6

KM-488~ROM USER GUIDE

GTLA Only a KM488-ROM acting as a System Controller may issue this

command. Use this command is used to send a Go To Local (GTL) Gl’lB command to those

devices

previously addressed to listen. This command

does not affect the state of the GPIB REN line.

Example

GTLA

LISTEN The KM488-ROM must be the Active Controller to execute this command.

This command addresses a given device(s) as a listener(s). LISTEN is trailed by the decimal GPIB address (0 to 30) of the device(s) to be addressed. When assigning multiple listeners, separate the addresses by one or more spaces.

Note that it is good practice to untalk and unlisten all devices prior to

sending a LISTEN command. (See the IJNT and IJNL descriptions.) Example LISTEN 2

LISTEN 5 9 30

LOC Use this command only if the KM488-ROM is acting as the System

Controller. When the LOC command is executed, it unasserts the GPIB RBN (Remote Enable) line. This action forces all devices on the GI’IB to the local state.

Example LOC

MLA The KM488-ROM must be the Active Controller to execute MLA (My

Listen Address). MLA forces the KM488-ROM to become a listener; it

sends a listen address co

mmand containing the GPIB address of the KM-

485ROM over the GPIB.

Example

b5A

MTA The KM-Q@-ROM must be the Active Controller to execute MTA (My Talk

Address). MTA makes the KM488-ROM the present talker (and onaddresses any other talker); it sends a talk address command containing the address of the KM488-ROM over the GPIB.

Example

MTA

REN This command can function only if the KM488-ROM is the System

Controller. The REN command asserts the REN (Remote Enable) Control

line on the IEEE-488 bus. Many devices require REN to be asserted before

they will accept commands or data.

Example

INTRODUCTION TO CALLABLE ROUTINES 3 - 7

3-8

SEC Use thls command in conjunction with TALK and LISTEN to specify a

secondary address. SEC must appear immediately after the primary address in a TALK or LISTEN command. The KM488-ROM must be an Active Controller to use SEC.

Example

TALK 3 SEC 5

LISTEN 4 SEC 8

TO If this command follows the DATA command, a Transmit Message

Terminator 0 will signal the end of data transmission. Section 3.2 describes the default values of the transmit terminators and how to change them. Set the terminators to one or two bytes, and send with or without EOI asserted on the last byte.

Example

DATA ‘Eello’ TO

If this command follows the DATA command, Transmit Message Terminator 1 will signal the end of data transmission. Section 3.2 describes the default values of the transmit terminators and how to change

them. Set the terminators to one or two bytes, and send with or without

EOI asserted on the last byte.

Example

DATA

‘Eello’ Tl

If this command follows the DATA command, Transmit Message Terminator 2 will signal the end of data transmission. Section 3.2 describes the default values of the transmit terminators and how to change them. Set the terminators to one or two bytes, and send with or without EOI asserted on the last byte.

Example

DATA 'Eello' T2

T3 If this command follows the DATA command, Transmit Message

Terminator 3 will signal the end of data transmission. Section 3.2 describes the default values of the transmit terminators and how to change them. Set the terminators to one or two bytes, and send with or without EOI asserted on the last byte.

Example DATA 'Eello' T3

TALK The KM488-ROM must be the Active Controller to execute this command.

TALK designates the specified device as a Talker and is followed by the decimal GPIB address ( 0 to 30) of the device. Remember that only one device can talk at a given time; thus, if multiple TALK commands are in a

command string, only the last one takes effect. Note that it is good practice to untalk and u&ten all devices prior to sending a TALK command (see the UNT and UNL descriptions).

Example TALK1

TALK 22

KM-488.ROM USER GUIDE

UNT. The KM488-ROM must be the Active Controller to execute this command.

UNLISTEN unaddresses the present listeners, if any. Example DNL

UNT The KM488-ROM must be the Active Controller to execute this command.

UNTALK is used to unaddress the present talker, if any.

Example

UNT

POLLING COMMANDS

PPC

PPD

PPU

SPD

The Parallel Poll Configure (PPC) command signals a previously addressed listener that a Parallel Poll Enable @‘FE) byte or Parallel Poll

Disable (PI’D) command is to follow. Note that not all devices support parallel polling.

PPC is rudimentary GPIB command byte and is thus sent using the CMD command (see Miscellaneous Commands). The CMD command immediately follows the PPC command; for example,

PPC

c&m nnn

Where nnn is the decimal value of the Parallel Poll Enable byte. This byte has the following

format:

OllOSPPP

Where S is 0 or 1. The addressed device will set the designated GPIB data line (determined by PPP) to the given value if service is required.

PPP

is a 3-bit value which represents a GI’IB data line (0 - 7). The

configured device will use this data line to respond to a parallel poll. Eurmple UNL LISTEN 6

MTA

PPC CbfD 101

The PPD (Parallel Poll Disable) command disables parallel poll response of any previously addressed listeners. PPD must always immediately

follow a PPC. Example

DNL LISTEN 12

MTA

PPC PPD

The I’I’U (Parallel Poll Unconfigure) command disables the parallel poll response of all devices on the bus.

Example PPV

The Serial Poll Disable (SPD) command returns the currently addressed

talker from the serial poll state to the “normal” talker state. Example SPD

INTRODUCTION TO CALLABLE ROUTINES 3 - 9

SPE The Serial Poll Enable (WE) command forces a device, previously

addressed to talk, to send its serial poll response instead of its normal data.

Example

UNL UNT b&A TALK 20 SPE

MISCELLANEOUS COMMANDS

CMD CMD indicates the next byte is to be sent as a GPIB command. A GPIB

command is any data byte sent in conjunction with the ATN control line asserted on the bus. The byte is must be specified in decimal format (range 0 to 255) and must follow the CMD mnemonic within the XMIT command string.

Example

PPC

CMD 96

DCL The Device Clear command forces all devices attached to the GPIB

(addressed or not) to a predefined state. The actual response of a device to this command is device-dependent.

Example

DCL

GET The GET (Group Execute Trigger) command synchronizes the start of a

devicedependent operation in all previously addressed listeners. In many devices, GET allows the KM488-ROM to trigger a measurement. This function is not supported by all devices.

Example

LISTEN 12 GET

IFC This command can only be issued by a KM-488-ROM which is the System

Controller. The IFC (Interface clear) command resets the interface state of all devices which are tied to the GPIB. It unaddresses all devices and forces the System Controller to become the Active Controller (if control had been passed to another device).

Example

IFC

LLO The LLO (Local Lockout) command allows you to disable the front panel

control of all devices that support this command. In many cases, this command works in conjunction with the GPIB REN signal. Local control may be restored with the GTLA or LOC commands.

Example

LLO

3-10

KM-488~ROM USER GUIDE

SDC

TCT

This command forces those devices attached to the GPIB and addressed to listen to a predefined state. The actual response of a device to this command is device-dependent.

Example

SDC

The (TCT) Take Control command allows the KM-488-ROM to pass control to another device ( with controller capabilities) on the bus, and is able to receive control. The device to receive control must first be addressed to talk.

Example TALK 5 TCT

XMITA

The XMITA routine programs the KM-488-ROM to send array data when the KM-488-ROM is a device or the Active Controller. XMITA also sends binary data; for example, data containing embedded line feeds or other control characters. Optionally, terminator characters may be used to mark the end of data or the data byte may be sent with EOI specified. XMITA allows the KM-488-ROM to send up to 61 KBytes of data from an array, and is especially useful in situations where KM488-ROM must send large amounts of data (up to 64K).

The XMITA routine transmits data stored in adjacent bytes within the computer’s memory, starting from a specified location. The data is transferred from the lowest specified memory address first, then from increasingly higher addresses until the end of the data is reached. In other words, the least significant byte of the first element of the array is the first character sent. The array may be of any data type, provided the language you are using has stored array elements of increasing index in increasing memory addresses, and the least significant byte of each location is the lowest address. The actual number of data bytes per location varies

according to the type of data elements contained within the array and the language being used. Refer to a language reference manual which describes the language that you are using for exact details.

Before you call the XMITA routine, be sure to designate the KM-488-ROM as a Talker. Hint: If the KM488-ROM is the Active Controller, call the XMIT routine with a My Talk Address (MTA) command. If the KM-488-ROM is a device, call the STATUS routine and check the state of the TA bit in the Address Status Register.

3.4 READING DATA

Once an instrument has taken a measurement, its data must be read into the computer, using any of the following routines:

ENTER

RCV

RCVA

INTRODUCTION TO CALLABLE ROUTINES

3-11

3-12

ENTER

Use this routine only if the KM-488-ROM is an Active Controller. The ENTER routine transfers data from the specified device through the KM-&S-ROM to the application program. Calling ENTER addresses the KM-488-ROM as a listener, the device at the specified GPIB

address as a talker, and asserts the GI’IB REN line. The received data is then placed into a

string specified within the ENTER call. This data string is returned with a status byte and a count variable containing the actual number of bytes received by the routine.

The ENTER routine retorns to the calling program when any of the following occur:

Calling ENTER when the KM-488-ROM is not the active controller.

Receiving a byte (other than the specified terminator) with the EOI signal asserted.

Receiving the specified message terminator (any one of the four default terminators may be selected).

Filling the receive data string.

Expiration of the timeout period.

NOTE: If programming in BASICA, you may modify the default receive terminator

sequences by running the CONFIG program. Otherwise, call the INTERM routine. See Section 3.2 for defaults.

When data reception is complete, all devices are at UNTALK and UNLISTEN. Therefore, to receive strings in “pieces,” avoid using ENTER.

All Carriage Returns and the receive message terminator character are stripped from the received data and are not stored within the string or included in the byte count. If the ENTER routine terminates due to reception of a data character with EOI asserted (other than the chosen receive terminator character), that character will be stored and included in the byte count.

Before you call the ENTER routine, be sure to set up a string to store the received data. Regardless of the language, you must allocate a string length greater than or equal to the number of bytes you expect to receive. Otherwise, data may be stored in areas allocated from

DOS or other parts of your program, and the program will crash.

RCV

Use this routine to program the KM-488-ROM to receive data when the KM-488-ROM is a

non-System Controller. RCV is useful in situations where KM-lSS-ROM must receive data concurrently with other listeners on the bus. The RCV routine is also useful when data must be received immediately after sending a string of commands with the XMIT command.

Received data is placed in the string named within the call. The data string is returned along

with a status byte, and a variable containing the actual number of received bytes. The RCV

routine stores data in a manner similar to ENTER (carriage returns and the message

terminator are stripped from the received data).

The RCV routine will return to the calling program when one of the following events occurs:

Calling RCV when the KM-488-ROM is not a listener.

Receiving the selected terminator character.

KM-488~ROM USER GUIDE

Receiving a data byte with EOI asserted.

Receiving the maximum number of bytes that will fit into the receive string.

Expiration of the timeout period.

Before you call the RCV routine, be sure to designate the KM-ISS-ROM as a listener. Hint:

If the KM-488-ROM is the Active Controller, call the XMIT routine with a My Listen Address (MLA) or LISTEN nn command. If the KM488-ROM is a device, wait until the KM&B-ROM is addressed to listen by the Active Controller by calling the STATUS routine and checking the state of the LA bit in the Address Status Register.

Set up a string to store the received data. Regardless of the language, you must allocate a string length greater than or equal to the number of bytes you expect to receive. Otherwise, data may get stored in areas allocated from DOS or other parts of your program, and the program will crash.

RCVA

The RCVA routine is similar to the RCV Routine in that it programs the KM-488-ROM to receive data when the KM-iSS-ROM is a device (not the Active Controller). The principal differences are that the RCVA routine stores the received data in a specified array and all received bytes will be stored. RCVA can also receive binary data; for example, data containing embedded line feeds or other control characters.

The received data is placed into the array named within the call. The number of bytes available for storage must also be specified. A status byte and a variable containing the actual number of received bytes are also returned. The RCVA routine stores every received character, including carriage returns and message terminator characters. These characters will also be included within the byte count.

The RCVA routine will return to the calling program when one of the following events occurs:

RCVA is called when the KM488-ROM is not a listener.

The selected terminator character was received (if terminators were enabled).

A data byte was received with EOI asserted.

The number of bytes specified in the COUNT parameter has been received.

The timeout period has expired.

Before you call the RCVA routine, be sure to designate the KM-488-ROM as a listener. Hint: If the KM-488-ROM is the Active Controller, call the XMIT routine with a My Listen Address (MLA) command. If the KM-488-ROM is a device, call the STATUS routine and check the state of the LA bit in the Address Status Register. You must wait for LA before calling RCVA.

Set up an array to store the received data. The number of bytes per array location will vary according to the type of array. When the array contains more than one byte per location, storage of the received data will begin at the least significant byte of the specified array location and progress in accordance with the manner most languages store data in arrays.

Regardless of array size or the language, you must allocate data storage greater than or equal

to the number of bytes specified in the count variable. Otherwise, data may be stored in areas allocated from DOS or other parts of your program, and the program will crash.

INTRODUCTION TO CALLABLE ROUTINES

3-13

Refer to the XMITA routine for a discussion of the relationship between number of array locations vs. number of data bytes.

3.5 TRANSMITTING/RECEIVING DATA VIA DMA

When using DMA, the computer transfers data directly between its memory and the KM-488ROM, resulting in the high speed transmission or reception of up to 64 KB of data to or from an array. In contrast, when transferring data while not using DMA, the computer transfers data between its memory and the device’s controller chip through registers in the microprocessor. Because the microprocessor must also execute other instructions, the rate at which it passes data far slower than when DMA is used.

The implementation of a DMA transfer is language-dependent. If you are programming in BASICA, you must call the DMA routine. Other languages initiate DMA by calling the RCVA and XMITA routines in conjunction with the SETDMA routine.

DMA

This routine works only in BASICA. The DMA (Direct Memory Access) routine permits high speed transmission or reception of up to 64K bytes of data.

This data is received into/transmitted from an array. In order to use the DMA routine, the KM-488-ROM must be assigned to a DMA “channel.” Each DMA channel consists of an address pointer and a pair of hardware signals. The KM488-ROM signals its need to transfer data via the DMA request signal (DMARBQ). Other logic in the system arbitrates control of the address and data busses between the microprocessor and the DMA controller. When the busses are available, the DMA controller places the contents of the address pointer register for that channel onto the address bus and notifies the KM-488-ROM that it is ready to perform the transfer via the DMA Acknowledge signal (DMA ACK). The DMA controller then generates all the other signals required to perform the transfer, with data passing directly between the KM488-ROM and memory.

DMATIMEOUT

This routine does not work in BASICA. DMATIMEOUT allows you to reset the length of time

to elapse before a DMA Timeout Error occurs. (DMA Timeout Errors are reported when XMITA and RCVA calls are used with DMA.) The default value of the timeout period is 10 seconds.

A DMA Timeout Error occurs when the time to transmit or receive an entire message exceeds

the set time. This is different from the I/O timeout, which occurs when the time between adjacent bytes exceeds the timeout value. Note that it may be better to set the I/O timeout period to a shorter length than the DMA timeout period.

NOTE: In BASICA, the DMA Timeout period is changed using the CONFIG program. See

Chapter 2.

SETDMA

This routine does not work in BASICA. The SETDMA routine, in conjunction with the XMITA and RCVA routines, initiates a DMA data transfer.

3-14 KM-488~ROM USER GUIDE

To perform a DMA transfer, the KM-@&ROM must be assigned to a DMA “channel.” Each DMA channel consists of an address pointer and a pair of hardware signals. The KM-488ROM signals its need to transfer data via the DMA request signal (DMAREQ). Other logic in the system arbitrates control of the address and data busses between the microprocessor and the DMA controller. When the busses are available, the DMA controller places the contents of the address pointer register for that channel onto the address bus and notifies the KM-488ROM that it is ready to perform the transfer via the DMA Acknowledge signal (DMA ACK). The DMA controller then generates all of the other signals required to perform the transfer, with data passing directly between the KM-488-ROM and memory.

The SETDMA routine designates a DMA channel for data transfers. The channel you assign must agree with the setting of the DMA Level Jumpers on the KM-488-ROM board (see Section 2.4). To initiate a DMA transfer,

Call SETDMA with the appropriate

channel number to

enable DMA transfer.

Call XMITA/RCVA.

Call SETDMA with a channel number other than 1,2, and 3 to disable DMA transfers.

3.6 CHECKING DEVICE STATUS

Generally, GPIB devices indicate whether or not they need servicing by means of serial polling and/or parallel polling. Often, serial polling and parallel polling are used together to determine the type of service needed by a device. This section describes those routines associated with serial and parallel polling. They include

. SRQ

SPOLL

POLL

SETSPOLL

NOTE:

The SRQ routine does not work in BASICA. When programming in BASICA, use

the STATUS routine to check the state of the SRQ signal.

SRQ

This routine does not work in BASICA. SRQ detects the state of the SRQ signal on the GPIB bus. When this routine returns a 1, it indicates

that the

SRQ line has been asserted. When the

routine returns a 0, it indicates that the SRQ line remains unasserted. SRQ response can be fed into a conditional statement within your program. For example,

normally you would want to conduct a serial poll only when the SRQ line has been asserted. In this case, you could call the SRQ function and then feed its result into a conditional which

would call an SPOLL if SRQ had been asserted.

NOTE:

Once you have obtained a TRUE response from the SRQ function, the SRQ response will reset to FALSE --even if the SRQ line is still active. In order to reset the SRQ response to TRUE, you must serial poll at least one device requesting

service. This action will reset the device’s SRQ line. At this time, if other devices were asserting SRQ, the output of the SRQ function would again reset to TRUE.

Otherwise, the SRQ function would become TRUE on the next assertion of the

SRQ line.

INTRODUCTION TO CALLABLE ROUTINES

3-15

SPOLL

The SPOLL routine allows the Active Controller to check the state of the devices tied to the bus. Devices may be polled “at will” or in response to the Service Request line (SRQ) being

asserted on the GPIB. Calling SPOLL will return the serial poll response byte from the addressed device.

The SPOLL routine does the following:

Addresses the specified device to talk.

Enables the specified device to send its serial poll response byte.

Receive the device’s serial poll response byte.

Disables the serial poll.

Untalks the specified device.

PPOLL

Use this routine only when the KM-488-ROM is an Active Controller. Calling this routine

initiates a GPIB parallel poll. The parallel poll, like the serial poll, is a mechanism allowing

the active controller to determine which device(s) need service. The parallel poll allows you

to quickly check the state of up to eight (groups of) devices simultaneously.

Before a parallel poll can be issued, each device to be polled must be assigned to a GPIB Bus

Data Line (DO - D7). This is the device’s response mechanism. If the device requires service

when the Parallel Poll command is issued, it will assert its designated bit within the data bus.

The assigned bit and its asserted value (0 or 1) must be preconfigured. This is accomplished

via a set of GLIB commands sent to the device over the bus.

To configure a device for Parallel Polling,

Address the device to listen.

Issue a GPIB Parallel Poll Configure @‘PC) command accompanied by a command byte to the device. (Hint: Use the KM-&S-ROM’s XMIT command.)

Once configured, the device will retain its parallel poll configuration until it is powered down (or reset by other hardware means), or until unconfigured by a GPIB Parallel Poll Unconfigure (IWJ) or Parallel Poll Disable W’D) commands.

A parallel poll is limiting in that it can determine only that a device(s) requires service. It cannot identify the specific conditions requiring service. In order to identify the condition(s), the KM-488-ROM must then perform a serial poll of each device requiring service (use the KM-488-ROM SPOLL command). The serial poll allows you to distinguish which device(s) need service and what type of service is required.

NOTE: Many GPIB devices do not support parallel polling. Check your device’s

documentation.

3-16

KM-488-ROM USER GUIDE

SETSPOLL

This routine allows you to program the serial poll response byte of the KM-488-ROM when it is acting as a device (non-Controller). The actual usage and meaning of each bit is userdefined. Optionally, it allows you to drive the SRQ line to request service from the Active Controller.

For example, consider an application where the KM-488-ROM transfers files from a computer containing a KM-488ROM acting as a device to a second computer containing a KM488ROM that is the system controller. You could define a simple protocol in which the device

(KM48-ROM1 is addressed to listen, and the controller passes a string containing a filename and a command byte. The command byte might signify a file read, write, create or append operation. If the command specified a read of a filename that could not be found, the device

would notify the Controller of this error condition using the SETPOLL routine. You would

define one of the Serial Poll Response bits to mean “File Not Found.” Then, you would call

SETPOLL, with the appropriate bits set. This would immediately notify the controller of the

error condition.

3.7 LOW-LEVEL ROUTINES

It is sometimes useful to be able to check the bits of the various GPIB Controller chip registers.

Two routines enable you to do this, as follows:

SETlNT

STATUS

SET/NT

This routine sets the Interrupt mask bits within the GPIB controller chip. The most common

reason for this is to allow the generation of interrupts upon receiving a Service Request (SRQ).

Other possible reasons include using the interrupts to enable detection of other bus related

events.

If the KM-488-ROM is acting as a device, SETlNT can check its address status. For example, using the ADSC (Address Status Change) interrupt would alleviate constant monitoring of the state of the TA (talk addressed) and LA (listen addressed1 bits in the Address Status Register.

It is important to note that when using interrupts, you must set up an interrupt service routine to handle the interrupting condition. The method for setting up such a routine is languagedependent. You must also assign the Kh4488-ROM to an Interrupt Level not used by other devices within the computer. The KM488-ROM contains an Interrupt Level selection jumper That must be set accordingly. Refer to the INSTALL program and Chapter 2 for assistance in setting the jumpers.

STATUS

The STATUS routine checks the status bits within the GPIB Interface Chip and also the state of DMA transfers. It is especially useful when the KM-488-ROM is acting as a device, rather than a controller.

INTRODUCTION TO CALLABLE ROUTINES 3-17

This routine can also

Examine the state of various setup parameters within the firmware. The STATUS routine obtains the value of the I/O Port Base address of the GPIB Controller Chip, the GPIB address of the Controller Chip, each of the four transmit/receive message terminators, and the timeout values used in conjunction with normal and DMA transfers. This function is particularly useful in a multiple board environment, or while developing and debugging software.

Read the state of the Interrupt Status registers within the GLIB Interface Chip. These registers provide information for using the KM488-ROM as either a device or the active controller. This feature may be useful in a “polling” environment (one in which software checks for certain conditions). When acting as the Controller, the STATUS routine may check the state of SRQ or, if interrupts are set up and enabled, the STATUS routine may check which conditions caused the interrupt.

When the KM488-ROM is acting as a device, STATUS can check for reception of a Group Execute Trigger (GET) or Device Clear (DCL) command by reading Interrupt Status Register

1. Interrupt status register 2 can be checked to see if the device has been set to local lockout or remote states. When the board is the active controller, STATUS can check the SRQI bit to see if the SRQ line has been asserted.

Whenever the state of the Interrupt Status Registers is read, all “interrupt” bits within the register are reset. It is important to note this when reading Interrupt Status Register 1. The XMIT and RCV routines check the Dl and W bits to determine when to read or write the next data character. If you read the Interrupt Status Register 1 and the first byte of data has been received, the Dl bit will be cleared. If the RCV routine is then called, it will “hang up” waiting for the Dl bit to set.

Read the state of the Terminal Count bits for each one of three possible DMA channels, by

setting the reg parameter to 3. This information is useful when using the BASICA DMA

routine in the “background” mode.

3.8 BOARD CONFIGURATION ROUTINES

This section describes those routines to use for a nonstandard interface setting. For example, if you are developing application programs in a language other than BASICA and have changed the factory-default setting of the I/O Base Address switch, you must call the SETPORT routine. (In BASICA, you will have to run the CONFIG program as described in Section 2.6.)

If an application requires the installation of more than one KM-488-ROM board in a single computer, you will use the SETBOARD routine (except in BASICA). In BASICA, each board has its own software EEPROM which must be assigned to its own base address. Boards are selected by using a DEF SEG statement to point to the desired board prior to the call.

SETPORT

You will use this routine only if you have changed the default Base Address (and are not programming in BASICA). If using multiple boards within a single computer, use SETPORT

to assign a “board number” to a given I/O port address.

3-18

KM-488-ROM USER GUIDE

SETWOARD

You will use this routine only if your system has multiple KM&?&ROMs. This routine

identifies the board to be programmed and thus is called prior to executing a series of

routines. Only the board identified with the SETBOARD routine will be affected, until another SETBOARD routine identifying another board is called. The “board numbers” are associated with the I/O Port Base Address of a given board.

3.9 MULTIPLE BOARD PROGRAMMING NOTES

In a multiple-board environment, set each board to either CONTROLLER or DEVICE mode,

and assign each board any legal GPIB address (including the same GPIB address as other

boards within the same computer). It is possible to assign multiple controllers within the

same computer. Note, however, that you will NOT be able to communicate between two KM488-ROM boards within the SAME computer, even if one is configured as a device and the

other as a controller.

In a multiple-board environment, the message terminator settings and timeout values are

GLOBAL parameters. In other words, all the KM-488-ROM boards within a computer share

the values of these parameters. The IOTIMEOUT, DMATIMEOUT, INTERM, and OUTTERM

routines are callable at any time, regardless of

the

board most recently selected, and the values

that are set will affect all of the boards.

When DMA is used, it will behave in a similar manner (DMA is enabled independently of the

board was selected at that time. A

call to the

XMITA and RCVA routines will use DMA on

every board once DMA has been selected at the time DMA was enabled.

INTRODUCTION TO CALLABLE ROUTINES 3- 19

3-20

KM-488-ROM USER GUIDE

Chapter 4

PROGRAMMING IN BASICA OR GWBASIC

While Chapter 3 gives a brief overview of the routines available for programming the KM48%ROM, this chapter gives instructions for calling the routines from BASICA and

GWBASIC. The routines appear in alphabetical order and include a sample program for each.

4.1 GENERAL

The KM-l&?-ROM uses an EEPROM (Electrically Erasable Read Only Memory) that contains

GPIB language extension for BASIC. BASIC uses the CALL statement to access those

language extensions within a user program. Before any CALL statement can function, it must

contain three definitions, as follows:

The memory segment address of the KM488-ROM library code.

The location of the mutine (offset address).

The parameters used by the routine.

Definition of the memory segment address of the interface should appear at the start of a user

program in a DEF SEG statement. This statement is followed by the memory address to

which the EEPROM is mapped. The memory address is a hexadecimal value; thus it should

have a &H prefix. The memory address must match the setting of the KM-488-ROM

Memory Address Switches. Refer to Section 2.4 for more information.

When multiple KM-%t%ROM boards are present in the same system, each must have its own

unique segment address. You may then select which of the boards is to be accessed by

executing a DEF SEG to its segment address.

BASIC requires identification of the offset address of each KM-488ROM routine to know where to call the routine from within the ROM. The offset address represents the number of

bytes the routine is offset from the DEF SEG address. Each KM-lSE-ROM interface routine

must have a variable set to the offset for that routine. For example, the offset for the INIT routine is zero; therefore, you must include the line INIT = 0 before calling the routine.

Note that you may use any name for these routines, so long as the alternate name matches the offset of the desired function. For example, if we define INIT = 0 and INITIALIZE = 0 within a program, the statements CALL lNIT and CALL INITIALIZE will execute the same function.

NOTE: You must define one segment address in every program and an offset address for

each KM-488-ROM routine. The most recent DEF SEG statement must reflect the starting address of the EEPROM on the board being used.

PROGRAMMING IN BASICA OR GWBASIC

4 - 1

Each KM-&&X-ROM Interface Routine requires certain parameters for execution. These parameters are always integer or string variables that must be defined prior to executing the CALL statement. The variable names must be enclosed in parentheses and follow the function name within the CALL statement. For example,

CALL INIT(ADRS%,bfCDE%)

These variables will pass values into and out of each of the call routines. When passing values into a call routine, you must equate a named variable of the appropriate type with the desired value, and subsequently pass that variable name into the call.

The example below shows the proper way to initiate a CALL statement sequence. It assumes

that the EEPROM is mapped to segment CC00 hex and the INIT routine has an offset value

of 0. In this example, the variable names ADRS% and MODE% pass the values 0,O into the

INIT routine. Note that you may assign any legal BASICA to these variables. However, the variables must be the correct data type and value, and must be passed into a callable routines in the same order as shown in the routine descriptions.

XXDEF SEG = SHCCOO

‘As~~iqns

mamory segment address

xxINIT=O : ADRS%=O : MODE%=0

'Gives offset

INIT

routine L variable

‘definitions

uCALL INIT(ADRS%,MODE%)

'uses call statement

Software Configuration

KM-488-ROM firmware contains a number of configuration parameters that govern the default settings of the input and output message terminator settings, message timeout periods, and I/O port addresses. If these default values are unsatisfactory, they may be changed by running the CONFIG program (see Chapter 2).

The default DMA and I/O Timeouts are 10 seconds. The default terminators are as shown in the following table.

TERM # OUTPUT TERMINATOR INPUT TERMINATOR

0 LF EOI

1 CR LF EOI CR 2 CR EOI , (comma) 3 LFCREOI

: (semi-colon)

Programming Notes

1. In BASICA, only variable names may be passed into and out of functions.

2. Be sure to include all the parameters for the Interface Routine. The parameters must be the same data type and appear in the same order as those given. You may, however, change their names. BASICA has no means for checking that the exact number of

parameters are given or that the parameters of the appropriate type. If you specify an incorkt number or type of parameters, your program may crash.

3. Strings are limited to the BASICA maximum of 256 characters.

4-2 KM-488~ROM USER GUIDE

4. All integers are treated by the KM-488ROM routines as unsigned values (0 to 655351. However, BASICA treats them as signed magnitudes (-32765 to +32767l. When you want to express a value which is greater than or equal to 32768, you will have to express it in one of two ways, as follows:

Convert it to a hexadecimal value. Be sure to prefix these values with &H when equating them to a variable name. Legal hexadecimal values range from 0 to AHFFFF and can be used to represent values from 0 to 65535.

Use unsigned values from 0 to 32767 as is, but for values of 32768 to 65535 subtract

65536.

5. The file HEADER.BAS is available to assist you with defining CALL routine offsets. This is a BASICA source file that predefines the offsets. It can be modified to suit your needs.

6. Do not give your variables the same name as any of the KM488-ROM routines.

4.2 DESCRIPTION FORMAT FOR ROUTINES

The format for each descriptions is as follows:

offset

usage

alternate usage

parameters

returns

notes

example

a brief description of the routine.

See Chapter 3 for more detailed

descriptions. . . . gives the BASICA offset for each routine. . . . gives an example of usage for each routine and assumes the input

parameters are passed in as variables. These parameters can also be passed in directly. See the General Programming Notes for more information.

. . . lists alternate usage

for

the routine, if any.

Unless otherwise noted, the

alternate usage performs exactly the same function as the usage.

. . . describes each of the input parameters. . . . describes any values returned by the routine. . . . lists any special programming considerations.

gives a programming example using the routine.

4.3 ROUTINES

- DMA

NOTE: DMA allows data transfer rates in excess of 100 kilobytes per second. However,

the actual data rates are limited by the rates at which other bus-connected devices can send or receive data. These rates are governed automatically by the GPIB

handshaking

signals.

purpo=

Initiates a DMA transfer.

offset 206

PROGRAMMING IN BASICA OR GWBASIC

4 - 3

- DMA (cont.)

usage

. . .

uDMA

= 206 ucount.% = umcde% = ustat% = 0

uDIY

DATA%

(100)

'Assigns storage space for

'received data useg% = uofs%=

VARPTR(DATA%(O))

XXCALL DMA(aeg%,ofs%,count%,mode%,stat%).

parameters seg% is an INTEGER representing the segment portion of the memory

address of the data. seg% is set to -1 to indicate the BASICA data

segment. ofs% is an INTEGER representing the offset portion of the memory

address of the data. This is usually obtained using the VARPTR function. The VARPTR function must be called immediately prior to the DMA function call, and all variables used within the program must be declared prior to the VARFI’R function. The reason for this is that BASICA can dynamically allocate storage space and if variables are declared after the VARPTR call, the array may be relocated and the data placed in the wrong location. This could cause your program to “crash”.

count% is an INTEGER containing the maximum number of data bytes to be transmitted or received. If you wish to send or receive more than 32767 bytes, you must express count% differently. See Programming Note 4 in the beginning of this section.

The DMA routine also performs “byte packing”; that is, two bytes of data are stored in each of the integer array locations. The first byte received is placed into the least significant byte of the first array location.

mode% is an INTEGER that defines the type of DMA transfer to be made and the operating characteristics of the DMA controller. The most common settings for mode% are &HZ005 for DMA input and &HZ009 for DMA output.

The mode byte format is Mode-High Byte

BIT 16 14 13 12 11

10 9 6

X X WAIT X X X X X

Mode - High Byte

BIT 7 6 6 4 3 2 1 0

MOD1

MOD0

ADEC INIT

OUT INP CSl cso

Where

X May be any value.

4-4

KM-488~ROM USER GUIDE

- DMA (cont.)

WAIT

cso, 1

INP

OUT

INIT

ADEC

This bit enables the DMA wait option. When this bit is 0, the DMA routine waits for the DMA transfer to be completed or a timeout to wcur before returning to the called program.

When this bit is 1, the DMA controller is setup for the transfer and control returns to the user program without waiting for the end of the transfer.

Select the channel for DMA transfer. Possible selections are as follows:

C!@

Select DMA Channel 1

0 Select DMA

Channel 2

1 1

Select DMA Channel 3

The selected DMA channel must agree with the setting of

the DMA Level Jumpers. See Section 2.4 for more

information. NOTE: Some DMA channels may be assigned to other

hardware within the PC. Check your PC system documentation to determine which channels are available.

When set to 1, this bit indicates the received data is written

to PC memory via DMA. Both this bit and the OUT bit

cannot be set to 1 at the same time. When set to 1, indicates the transmitted data is read from

PC memory via DMA. Both this bit and the INP bit cannot

be set to 1 at the same time.

Enables DMA autoinitialize mode, when it is set to 1. Under normal circumstances, the DMA controller transfers

the specified number of bytes to/from the PC memory from the given starting address and terminates when completed.

When the AUTOINITIALIZE mode is enabled, the DMA

controller will reset the byte count, reset the initial address, and repeat the transfer again. This continues indefinitely until the DMA routine is called with INIT=O.

Controls the direction in which the DMA controller generates its addresses and obtains data. If ADEC = 0, the DMA controller is set to address increment mode. This means that the data is accessed from successive locations with ascending addresses within the PC memory. This mode is most often selected because it duplicates the manner in which array locations are accessed from the calling program.

If ADEC = 1, the DMA controller is set for address decrement mode. This means that the data is accessed from

subsequent locations with descending addresses.

PROGRAMMING IN BASICA OR GWBASIC 4 - 5

- DMA (cont.)

MODO, 1

The DMA controller within the PC is capable of operating in three distinct modes. These two bits set the DMA controller mode. Available selections are

MOD1

MOD0

MODE

Demand Mode

0 1

Single Mode

0 Block Mode

Descriptions of these three modes follow. Demand Mode -In this mode, when the DMA Request line

is asserted the DMA controller assumes control of the bus. The DMA controller retains control of the bus until the DMA request signal is unasserted. Once this signal has

been unasserted for more than one processor clock cycle,

control of bus is returned to the microprocessor. This mode

allows the DMA controller chip to pass data at a slightly

faster rate and the microprocessor to access the bus when it

is not needed.

Single Mode - In this mode, when the DMA Request line is

asserted the DMA controller assumes control of the bus and

transfers a single byte of data. Control of the bus is then

returned to the microprocessor. Block Mode - In this mode, the DMA controller gains

control of the bus and remains in control until the specified number of bytes has been transferred, regardless of the state of the DMA request line. Block Mode allows the fastest data transfer rate possible.

NOTE: BLOCK MODE IS NOT RECOMMENDED FOR MOST APPLICATIONS. This is because when block mode is selected, all other DMA channels are locked out and the microprocessor

cannot execute any

bus cycles. This can be dangerous in some circumstances. For example, in many PCs (particularly the older XT type machines), one of the DMA channels was used to refresh the dynamic RAM chips. (These store user programs and data.) If memory refresh were to be halted for an excessive period of time (hundreds of microseconds), all data within the RAMS would be lost.

stat% is an INTEGER describing the state of the transfer returned after

the call. This stat% word differs from the one used in other routines because it indicates when “warning” conditions, as well as error conditions, occur. A warning differs from an error in that some (or all) of the transfer may have completed.

If the most significant bit of the stat% word is set, a warning has occurred. This results in a negative stat% value.

The stat% value is interpreted according to the following format:

4-6

KM-488-ROM USER GUIDE

DMA (cont.)

Stat

(Output)

-High Byte

BIT

15 14 13 12

11 10 9 8

WARN 0

0 0 0 0

0 0

Stat fOutput1

-High Byte

BIT

7 6 5 4

3 2 1 0

0 0 0 0

TM0 IOER MDER CSER

WARN

CSEA

MDER

TM0

NOTE: The meaning of the stat%‘s low bits is dependent on the setting of the WARN bit.

Warning. If this bit is set to 1, the other bits in stat% indicate that a Warning has occurred. If it is set to 0, the other bits indicate that an Error has occurred.

The following are Warning indications (WARN=l):

Address Wraparound Error. If CSER=l and WARN=l, an

“address wraparound” has occurred. This condition arises as a result of hardware limitations within the PC. The DMA controller within most PCs generates 16 bits of address;

however, a ZO-bit address is required by the PC. Most PCs

generate the four additional address bits with a “page

lines. Address wraparound occurs whenever the DMA

controller counts past its maximum count (FFFF rolls over

to OiKlO), because there is no mechanism to “carry” the most

significant bit into the page register.

For example, if the DMA routine were called with the SEG

parameter set to ZOOO, and the OFS parameters set to FFFF,

the DMA controller would be loaded with a count value of

FFFF, and the page register with a 2. The first location

accessed would be absolute address 2FFFF. The DMA

controller would

then increment its address (to O), however

the page register would not change. Thus, the next location

accessed would be 2ooo0, rather than 3DDDD.

Mode Error. If MDER=l and WARN=l, it signifies that an

invalid Mode Selection was made (see the MODE

parameter description). The DMA routine substitutes

Demand Mode (00) and continues.

Timeout Error. If this bit = 1 and WARN=l, it signifies a

Timeout Error. A Timeout Error indicates that the transfer

was not completed during the designated DMA Timeout

Period. It is possible for the timeout period to expire during

a transfer of a large number of bytes to or from a slow

device, even if the transfer occurs correctly.

The following are Errors fWARN=OI:

PROGRAMMING IN BASICA OR GWBASIC

4.7

- DMA (cont.)

IOER

Input/Output Error. If this bit = 1 and WARN=O, it indicates than the DMA routine has been called with an invalid selection of the INP and OUT bits in

the

mode parameter. Either INPUT or OUTPUT must be selected; but not both.

CSER

DMA Channel Select Error. If CSER=l and WAR&O, it indicates that an invalid DMA channel (channel 01 was selected for the transfer.

notes When calling DMA, you must declare an INTEGER array to store

received data. Since each integer in BASICA uses 2 Bytes of memory, the total number of array locations allocated must be equal to or greater than one half the total number of bytes to be received.

exa!trp/e This example shows how to avoid an address wraparound error. The

program transfers data into the computer’s memory at an even segment boundary. This boundary is above the area used by DOS and your

program (for example, &H70001. The data can then be moved into an array using the BASIC PEEK instruction. Note that this example stores one byte per array location.

100 110 120 130 140 150

160 170 180

190 200 210 220

230

240

DYA - 206

'DMA or11 Off.& ccQuT% - 1028 'Trane?ar 1026 points DuAcPPS% -0

'St.rt with first array slomont NODE% - 6E2005 'Input. DM% Ghan 1

STAT% - 0 'Initialira variabls

DEF es5 -0

‘w&SIC’. l sgmant

DIM WAVE%(tll) DMASEC% - CR2000 DEF SEC - CECCOO 'KM-488~Roll memory segment CAI& D~(DHASED$,DIIAOFBX%,CDDNT%,MODE%, STAT%) IP (STATUS%<> 0 ) TEES PRIUT "FAILED", STAT% :

STOP

DEP 8EG - D-EC% 'Cat data

from

manwry to .rn.y

POR

- 0 TO CODXT%-1

wAvE%(I%)

- PEEK(I%)

tam

- ENTER

purpose Addresses a specified device to talk, the KM-488-ROM to listen, and

receives data into a string from the addressed device.

offset 21

. .

xx ENTER-21 xx

infob - SPACE$(mru.ah.rs%) '(max.ohara% < 256) xx lurg% - 0 P drS% xx mtat% - 0

xx CArL liwJ!ER (info8,lang%,akm%,

et&,%)

. . .

xx RCV$ -

LIWTB

(info$,

lsnq%)

. . .

4-8 KM-488~ROM USER GUIDE

- ENTER (cont.)

pafameters Mo$ is a STRING (up to 256 characters) which is to hold the received

data. The string must be long enough to receive the expected number of characters. Carriage returns and the message terminator character in the incoming data are ignored and not stored with the received data. You

should use the BASIC SPACF$ function to declare a string which is long

enough to store the expected maximum number of characters to be

received. After the data has been received, it should be copied into a new string which has been “trimmed” to length with the BASIC LEm$ function. Or else, you may trim the first string to length, provided that

you resize it with the BASIC SPACE$ function prior to calling the

ENTER function again. a&s% is an INTEGER containing the IEEE bus address of the device

that will sent the data and the terminator to be used. This byte is of the following format:

Adrs (Input Parameter) - Low Byte

BIT 7

6 5

TRMl TRMO 0

ADR4 ADR3 ADR2

ADRl

ADRO

Where

TRMl-0

Terminator Select. These two bits select the Message Terminator to be used to signal the end of a transmission.

Available terminator selections are

TRMl TRMO TERMINATOR # DEFAULT

0 0 0 LF 0 1 1

1 0

1 1

These terminators are defined upon system configuration and are stored

(along

with the BASICA library code) in the EEPROM. They can be changed by running the CONF’IG program as described in Chapter 2.

The easiest way to specify an alternate terminator is to add a factor to the GPIB address of the desired instrument which is specified within the ENTER call. The factors added for each terminator are as follows:

GPIB Address + 0 = Terminator 0 GPIB Address + 64 = Terminator 1 GPIB Address + 128

= Terminator 2

GPIB Address + 192

= Terminator 3

For example, if you wanted to receive a message using terminator 2 from a device at GPIB address 10, the value of adrs% supplied to ENTER would be 138 decimal (10 + 128).

ADR4-0

GPIB Address. These five bits are used to represent the GPIB address of the device to which the data is to be sent. GPIB addresses can range from 0 to 30.

PROGRAMMING IN BASICA OR GWBASIC

4 - 9

- ENTER (cont.)

fetumS info$ is a STRING variable, up to 256 characters, which will contain the

string, 2) the specified terminator is received, or 3) any character is

received with the

EOI

signal asserted. Carriage returns and the

terminator character in the incoming data are ignored and not stored with the received data. However, bytes other than the terminator which are received with EOI asserted will be stored.

leng% is an INTEGER, less than or equal to 256, which indicates the actual number of bytes which were stored. This number does not

include message terminator characters or carriage returns.

stat% is an INTEGER which describes the state of the transfer returned after the call. If a stat value of 0 is returned, the transfer completed

normally. Otherwise, the returned stat values (or combination of) are

interpreted as follows:

Stat (Return) -Low Byte

BIT 7

1 0

0 0

TM0 OVF NC

ADRS

Where

TM0 Timeout Error. Indicates whether or not a Timeout Error

occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

OVF

Overflow Error. If this bit is a 1, then the info string was

filled, before a terminator character or EOI was detected.

KM-468-ROM not an Active Controller . If this bit is set to a 1, it indicates the routine was called before the KM-488ROM was designated as an Active Controller.

ADRS

Invalid GPIB address. If this bit is set to 1, then an invalid GPIB address was given.

example In the following example, data is sent from two different instruments to

a KM-l&ROM. The KM-488-ROM is acting as the System Controller and is assigned to GPIB address 0. One of the two instruments is a

voltmeter, requiring a Carriage Rehnn-Line Feed terminator combination, assigned to GPIB address 7. The second instrument, located at GPIB address 10, requires a line feed as its terminator.

The voltmeter is first sent a string of data which represents its instrument

setup command. Then, when addressed to talk, it sends its most current reading to the KM-&J-ROM. The second instrument is instructed to

send its status, when addressed to talk. It is assumed that the string sent by both instruments is 25 characters or less. The string is printed out on

the computer screen.

4-10

KM-488~ROM USER GUIDE

10 20 so 31 32

34 36 40 4s so 60 70 SO 90 100 110 120 I.30 140 150 160

170 172 180 190 200 210 220 230

2‘0

250

260

270

- INIT

purpose Initializes a KM438-ROM by assigning it a GPIB address and

establishing it as a System Controller or Device.

offset 0

usage . . .

IUIT - 0 xx a&*%- : mode%P 0AI.L IWIT(a&a%,modo%)

. . .

PSrS!rkVSrS adrs% is an INTEGER representing the IEEE bus address of the KM-488-

ROM. This is an integer from 0 to 30.

PROGRAMMING IN BASICA OR GWBASIC

4-11

- INIT (cont.)

mode% is an INTEGER representing the operating mode of the KM-488ROM. These can be any of the following values:

Mode-Low Byte

BIT 7

6 4

X X

X X X

FAST DEV X

Where

X May be any value.

FAST

Handshake Speed. If this bit is set to 1, High Speed GPIB bus handshaking will be usedQOOns.). If it is set to 0, Low Speed GPIB bus handshaking (2 s.) will be used. See Chapter 3 for more information regarding the handshake

speed.

DEV Device. If this bit is set to 1, then the KM-488-ROM is acting

as a Device. Otherwise, when this bit is set to 0, the KM488ROM is acting as a System Controller. When System Controller is selected, the GLIB IFC line is momentarily asserted.

refurfls None.

example This example initializes the KM-488-ROM as a System

Controller

with a

IEEE address of 0 with a High Speed Handshake.

DNF sEc-sEccoo

20 INIT=

30 AoNa%-o : NOON% -4

CALL INIT (Z&INS%, NODE%)

- PPOLL

PvP-e

Initiates a Parallel Poll and returns a parallel poll response byte. NOTE: Many GPIB devices do not support parallel polling. Check your

device’s documentation.

offset 15

usage . . .

xx PPOIZ - 15 xx rs*p% - 0 xx PPOLL(rs~p%)

. .

parameters None.

returns resp% is an INTEGER which will contain the parallel poll response.

4-12

KM-488sROM USER GUIDE

- PPOL (cont.)

notes Before you call the PPOLL routine, you must configure the Parallel Poll

response of the device. To do this,

Address it to listen.

Send it a GI’IB Parallel Poll Configure (PPC) command, using the

XMIT command.

Send a Parallel Poll Enable byte using the KM488-ROM XMIT command. (Use the mnemonic CMD followed by nnn where nnn is the decimal value of the Parallel Poll Enable byte.

The Parallel Poll Enable Byte is of the format OllOSPPP, where

S is the parallel poll response value (0 or 1) that the device

uses to respond to the parallel poll when service is required. PPP is a 3-bit value that tells the device being configured

which data bit it should use as its parallel poll response CD101 through DIOB).

example This example assumes that the KM-488-ROM is connected to a Sorenson

HPD3010 Power Supply. This device is located at GI’IB address 1. It is also assumed that this device drives bit 3 of the Parallel Poll Response byte to a logic “1” when service is required. To program the device to respond properly, send the Parallel Poll enable byte 01101011 (107) via the XMIT command.

- RCV

purpose Receives data into a string.

offset

usage

. . . xx Ncv-6 P info+ sPAce$(mu.oharm%) '(mar.ohar.s% < 256) xx hog%= xx

.t.t% -

xx CALL Rev (info$,leng%,*tat%)

. . .

NOTE: The alternate usage assumes the use of Input Message Terminator 0.

PROGRAMMING IN BASICA OR GWBASIC

4-13

- RCV (cont.)

paramefers Mo$ is a STRING (256 characters max.) which will hold the received

data. The string must be long enough to receive the expected number of characters. Carriage returns and the message terminator character in the incoming data are ignored and not placed in received data. However, bytes other than the terminator received with EOI will be stored. You should use the BASIC SPACE$ function to declare a string which is long enough to store the expected maximum number of characters to be received. After the data has been received, it should be copied into a new string and “trimmed” to length with the BASIC LEm$ function.

NOTE Before calling RCV, stat% must be initialized for terminator selection.

stat% is an INTEGER that selects the input terminator to be used. ‘Ike terminator (stat%) values follow:

Stat (Input) - Low Byte

BIT 7

5 4 3 2

1 0

TRMl TRMO X

X X X

X X

Where

May be any value.

TRMl-0 Terminator Select. These two bits select the Input Message

Terminator to be used to signal the end of a transmission. Available terminator selections are

TRMl TRMO

TERMINATOR #

DEFAULT

1 1

1 0

These terminators are defined upon system configuration

and are stored (along with the BASICA library code) in the EEPROM. To change their values, run the CONFIG program as described in Chapter 2.

info$ is a STRING variable (256 characters max.) containing the received data. The string must be long enough to receive the expected number of characters. Enter will terminate reception of data when 1) the number of characters received exceeds the length of the string, 2) a message terminator is received, or 3) any character is received with the EOI signal asserted. Carriage returns and the message terminator in the incoming

data are ignored and not placed in received data. However, bytes other than the message terminator received with EOI are stored.

leng% is an INTEGER, less than or equal to 256, which indicates the actual number of bytes which were received and stored.

stat% is an INTEGER which describes the state of the transfer returned after the call. The returned stat% values (or combination of) are interpreted as follows:

4-14 KM-488-ROM USER GUIDE

- RCV (cont.)

Stat (Return) - Low Byte

BIT 7

6 6 4

3 2 1

0 0 0

TM0 OVF NL

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

OVF

Overflow Error. If this bit is a 1, then the RCV routine received more characters than could fit into the info string.

KM488-ROM not a Listener. If this bit is set to a 1, it indicates the RCV was called before the KM-488-ROM was designated as a Listener.

note9

The KM4?8-ROM must be addressed to listen and a device must be

addressed to talk prior to calling this routine.

ex&?f1@8 This example shows how the RCV routine might be used together with

the XMIT routine to receive data. It uses the XMIT routine to command

a Keithley 196 voltmeter to take a reading. The meter reading is received

using the RCV routine. It is assumed that the meter reading retomed

will fit into a 25-character string.

This example assumes that the KM-488-ROM has been configured such

that transmit message terminator 1 is Carriage Return-Line Feed

combination and this combination is also used by the Keithley 196.

10 DEF SEG-CSCCOO

20 IUIT - 0 : WIT - 3

: RCV-6 : ADRS%-0 : MODE%=0 30 CALL IWIT(ADRS%,MODE%) 40 SETDPWTtEN DNI, DNT

IJSTE~

7 MTA DATA 'POR381T3X' Tl GET

UULIMTTAIX7MLP." 50 CALL XMIT (9ETOP$,STAT%) 60 IP (STAT%OO) THEN PRINT

“Error

sading and &ring

9tatua-";

STAT%

70 RCVDAT$=SPAcE$(25)

'Allooato *paae for roooivo data

STAT%-0

'USS Input terminator 0 81 RcvLEW% - 0 90 CALL RCV(RCVDAT$, -%, STAT%) 100 LF

(STAT%<>)

TEEU PRINT "RCV Status

Error

Status=":STAT% 105 DA!l'$ - IJWT~(RCVDAT$,RCVLEN%) 110 PRINT "Reosivad &t~-":DAT$:"LMcJthi";RCVLEN%

- RCVA

purpose Receives data into an array.

offset 203

PROGRAMMING IN BASICA OR GWBASIC 4-15

- RCVA (cont.)

usage

. . .

P EVA-203 xx DIY ISmDAT%(N%) xx

l g% -

P ofa% -

P mmxlsn% - 2*u% P lavlM% xx

atat% -

ofa%-VARVTR(indat%(O))

P CALL RCVA(~sg%,of~%,murlon%,mvllsn%,~tat%)

alternate usage

~Y(~eg%,of~%,nurlsn%,ro"lsn%,‘t*t%)

NOTE: The alterante usage assumes the use of Input Message Terminator 0.

parmefers

seg% is an integer representing the segment portion of the memory address of the data. seg% is usually set to -1 to indicate the BASICA data segment.

ofs% is the offset portion of the memory address of the data. This is usually obtained using the VARPTR function. The VAWTR function must be called immediately prior to the RCVA function call and all variables used within the program must be declared prior to the

VARPTR function. This is because BASICA dynamically allocates

storage space and if variables are declared after the VARPTR call, the array may be relocated and the data will be placed into the wrong location. This may result in a program crash.

maxlen% is an INTEGER containing the maximum number of data

bytes to be received. See Programming Note 4, found at the beginning of

this section, if you want to send more than 32767 bytes.

stat% is an INTEGER which selects the type of terminator to be used. This parameter must be initialized every time you call the RCVA routine. This integer is interpreted according to the following format:

Stat (Input Parameter) - Low Byte

BIT 7

5 4

2 1 0

STRM TRMl

TRMO X

X X

Where

STRM

Enable/Disable String Message Terminators. If this bit is 1, a Message Terminator Character will be used to detect the end of reception. If this bit is 0, a Message Terminator Character will not be used.

TRMl-0 Terminator Select. These two bits select the Input Message

Terminator to be used to signal the end of a transmission. (The STRM bit must be set to 1.1 Available terminator selections are

4-16

KM-488~ROM USER GUIDE

- RCVA

(cont.)

TRMl TRMO TERMINATOR # DEFAULT

0 0

0 LF

0 i

:. CR 1 1 1

The values for these terminators can be changed by running the CONFIG program as described in Chapter 2.

returns rcvlen% is an INTEGER containing the actual number of data bytes

which were received. stat%

is an INTEGER describing the state of the transfer returned after

the call. The RCVA routine returns three status bits within the STAT variable.

The TM0 bit is used to signal a timeout error. The REOI bit signals that the routine returned because the terminator was detected (if enabled), or EOI was received. The NL bit is set if the RCVA routine was called and the board was not addressed to listen. Unlike other KM-488-ROM routines, it is possible to return a non-zero status when the call was completed successfully.

Stat (Return) -Low Byte

BIT 7

6 5

2 1

0 REOi

0 TM0

0 NL 0

REOI Reason for RCVA Termination. If this bit is a 1, then RCVA

routine ceased because an EOI or terminator character was received. If this bit is a 0, then the RCVA was terminated because an error occurred or the maximum byte count was reached.

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

NL KM-488-ROM not a Listener. If this bit is set to a 1, it

indicates the RCVA was called before the KM-488-ROM was designated as a Listener.

1. The KM-488ROM must be addressed to listen before calling this routine.

2. When calling RCVA, you must declare an integer array to store received data. Since each integer in BASICA uses 2 bytes of memory, the total number of array locations allocated must be equal to or greater than

one half the total number of bytes to be received.

3. The maxlen% parameter must not exceed twice the number of array locations or else the data will be stored into an area of memory which

has been allocated to different parts of the system.

PROGRAMMING IN BASICA OR GWBASIC 4-17

- RCVA (cont.)

This example illustrates a typical way to use RCVA.

Purpose

offset

usage

parameters

SEND

Addresses a specified device to listen, the KM-488-ROM to talk, and

sends data from a string. 9 XXSEUD - a

xx. a&*%=

: stat% - : info5 - 1). , .”

x.x CALL BEaD (drs%,info$,*t*t%)

. . .

adrs% is an INTEGER containing the IEEE bus address of the device

that the data is to be sent to and the terminator to be used. This byte is of

the following format: Adrs (Input Parameter) - Low Byte

BIT 7 6

5 4 3 2

TRMl

TRMO 0

ADR4

ADF13 ADR2 ADRl ADRO

Where

TRMl-0 Terminator Select. These two bits select the Input Message

Terminator to be used to signal the end of a transmission. Available terminator selections are

TRMl

TRMO TERMINATOR #

DEFAULT

0 0 0 0 1 1 ii

1 1

The values for these terminators can be changed by running the CONFIG program as described in Chapter 2.

The easiest way to specify an alternate terminator is to add a factor to the GPIB address of the desired instrument

which is specified within the SEND call. The factors added for each terminator are as follows:

4-16 KM-466~ROM USER GUIDE

- SEND (cont.)

GPIB Address + 0

= Terminator 0

GPIB Address + 64

= Terminator 1

GPIB Address + 128

= Terminator 2

GPIB Address + 192

= Terminator 3

For example, if you wanted to send a message using message terminator 2 to a device at GPIB address 10, the value of adrs% supplied to SEND would be 138 decimal (10

+ 128).

ADRGO

GPIB Address. These five bits are used to represent the GLIB address of the device to which the data is to be sent. GLIB addresses can range from 0 to 30.

Info$ is a STRING (256 chars max.) containing the data to be sent.

returns stat% is an INTEGER describing the state of the transfer returned after

the call. The returned stat values (or combination of) are interpreted as follows:

Stat (Return) -Low Byte

BIT 7 6 5

2 1 0

0 0 0 0 TM0 0

ADRS

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

NC Not Active Controller. If this bit is a 1, then the SEND

routine was called when the KM-488-ROM was not an Active Controller.

ADRS

Invalid Address. If this bit is set to a 1, an invalid IEEE-488 device address was given.

examp/e This example shows how to send data from a KM-488-ROM to a device.

The KM4?8-ROM is initialized as a System Controller located at GLIB address 10. The KM488-ROM uses high-speed handshaking. The data

(a device setup string) is sent to a device located at GPIB address 2 using terminator 0.

DES" SEG-LECCOO

‘Assumes

NNPROM is at CHCCOO

20 'change to suit

your l

etup

25 INIT - 0 'Offset

of INIT

routinn

30 9NNDn9

'Offast

SEND routine

40 Arms%-10 : MclnE%-4

‘a&up a‘ ay&xm

Controllsr at

'GPIB

adrs 10 with High Spsod

'kkndshaks

60 CALL INIT (ADl=,S% , XODE%) 70 'Dsalars .&up string and addroes 80 1

instrument

90 SNTDP$-~~POROTOMOX" : AD=%=2 : *TAT% -0 100 CAI& SSND

(ADBS%,SET(IP$.BTAT%)

110 IP STAT <> 0 TEEN PRINT "Error sonding Status=";STAT%

PROGRAMMING IN BASICA OR GWBASIC 4-19

- SETINT

putpose Sets the m-488-ROM’s interrupt enable bits.

offset

212

usage . . .

8ETINT - 212 xx intvrl% P

CALL SETINT(izitval%)

. .

parameters IntvaI% is an INTEGER containing the address and value of the

Interrupt Mask Register. This is interpreted as follows: INTVAL (Input) -High Byte

BIT 7

6 5 4 3 2 1 0

X X X X

X X X ADRS

Where

X May be any value. ADRS If this bit is set to 0, bits 0 through 7 will be written to

Interrupt Mask 1. If this bit is set to 1, bits 0 through 7 will be written to Interrupt Mask 2.

INTBRRUFF MASK 1

INTVAL (Input) -Low Byte (ADRS = 0)

BIT 7

6 5 4 3 2 1 0

0 0 GET 0 DEC 0 0 0

Where

GET

DEC

When this bit is set to 1, an interrupt will be generated when a KM-488-ROM acting as a device received a GPIB GET (Group Execute Trigger) command while addressed to listen.

When this bit is set to 1, an interrupt is generated when a Device Clear is received.

INTERRUPT MASK 2

INTVAL (Input) -Low Byte (ADRS = 1)

BIT 7 6 5 4 3 2 1 0

0 SRQI 0 0 0 LOKC REMC ADSC

SRQI When this bit is set to 1, an interrupt is generated when

SRQ is received.

LOKC

When this bit is set to 1, an interrupt is generated when the state of the Local Lockout bit changes.

4-20 KM-488-ROM USER GUIDE

returns

notes

examp/e

wwse

offset

usage

parameters

SETINT (cont.)

REMC When this bit is set to 1, an interrupt is generated when the

state of the Local/Remote bit changes.

ADSC

When this bit is set to 1, an interrupt is generated when the

state of the LA, TA, or CIC bits within the address status

interrupts. In BASICA, the most common way to handle interrupts is

through a routine which maps the interrupt into BASICA’s lightpen

interrupt,

allowing

you to execute a BASICA ON PEN statement to

execute the interrupt service routine.

This example shows you how to use the SETINT routine to enable the

SRQ interrupt.

DER SE0 - 4HCCOO

20 SSTIST - 212 30 IuTvAL% - itI 40 CALL WTIUT (IUTVAL~) ‘Enable SRQ

intarrupt

SETSPOLL

Defines the Serial Poll Response of a KM-488-ROM acting as a device (non-Controller).

215

xx SETWOLL - 215 P n.p* xx CALT

SETSPOIL

(reap%)

resp%

is an INTEGER describing the serial poll response and the state of

the SRQ bit. This byte is of the following format: Resp% (Input) - Low Byte

BIT 7

6 6

1 0

SPRS RSV SPR6 SPR5 SPR4 SPR3 SPRZ SPRl

Where

SPRl-6

Bits 1 through 8 of this device’s Serial Poll Response Byte.

RSV

If this bit is 1, SRQ will be asserted to request servicing. Otherwise, SRQ

will not be asserted.

returns

None.

PROGRAMMING IN BASICA OR GWBASIC

4-21

- SETSPOLL (cont.)

This example illustrates a common use of SETSPOLL.

- SPOLL

purpose

Performs a serial poll of the specified device.

offset 12

usage

. . .

XXWOLL-12

xx. a&a% -

xx rsspe -

&Gate

xx CrLLL WOLL (adz*%, rsape, *tat%)

parameters

adrs% is an INTEGER containing the IEEE bus address of the device that is to be serial polled. This can range from 0 to 30.

returns

resp% is an INTEGER containing the serial poll response received. The definition of this integer varies from device to device; however, Bit 6 is always used to indicate whether the device is in need of service. Consult the manufacturer’s operator’s manual for more information.

stat% is an INTEGER describing the state of the transfer returned after the call. The stat value is interpreted as follows:

Stat (Return) -Low Byte

BIT 7

6 4

2 1 0

0 0 0 0 TM0 0 NC ADR

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

KM48-ROM not a Controller. If this bit is set to a 1, it indicates the routine was called before the KM-488-ROM was designated as an Active Controller.

4-22 KM-466~ROM USER GUIDE

example

SPOLL (cont.)

ADR

Invalid GPIB Address. If this bit is set to 1, an invalid GLIB address was provided.

This example illustrates a simple serial poll of a device located at GLIB address 10.

10 20 25 30

60 70

im-

usage

parameters

BIT 7

6 6 4

3 2 1

X X

ADR3

ADR2 ADRl

ADRO

STATUS

Returns the current setting of the requested status parameter.

STATUS - 209

xxrrlJ% xx *tat% Xx CALL

STATUS

(rag%, &at%)

reg% is an INTEGER containing the address of the register or

configuration parameter to be queried. This value corresponds to a 4-bit field specifying the status register or configuration parameter to be read.

The format of the reg% byte is as follows:

Reg (input) - Low Byte

May be any value.

ADR3-0

REGISTER/PARAMETER SELECT. This is a 4.bit field which specifies the status register or configuration parameter to be read. Registers and parameters are selected as follows:

PROGRAMMING IN BASICA OR GWBASIC

4 - 23

STATUS (cont.)

ADR3

ADRZ

ADRl

ADRO

0 0 0

0 Addregs statu8 Re*

0 0 0

1 htemlpl status 1 Reg

0 0 1

0 InterNpI statw 2 aeg

0 0 *

1 DMA StalusReg

0 1 0

0 output Tdstor 0

0 1 0

1 output TermlnatM 1

0 1 1

0 output Temunator 2

0 1 1

1 output Terminstor 3

1 0 0

0 Input Terminator 0

I 0 *

1 Jnput Terminator 1

1 1 1

0 Input Terminator 2

1 1 1

1 Input Terminator 3

1 0 0

0 I/O nmeo”t Parameter

1 0 0

1 DMA Timeo”t Parameter

1 1 1

0 I/O Port Address

1 1 1

1 GPIB Address of KM488-ROM

returns reg% -When STATUS obtains the value of one of the four transmit

message terminators, this variable will contain two flag bits which detetine the length of the terminator and whether or not EOI is asserted with the last byte. When obtaining other parameters, reg% will retain its input value.

Reg (Return) -Low Byte

BIT

7 6 5 4

3 2 1 0

0 0 0 0 0

0 LEN EOI

Where

LEN

Terminator Length. If this bit is set to 0, then the terminator

is one byte long. If this bit is set to 1, then the terminator is two bytes long.

EOI

If this bit is set to 1, EOI is asserted when the last terminator

byte is sent. Otherwise, EOI is not asserted.

stat% is an INTEGER describing the status bits for the register or the configuration parameter which was specified by the reg% parameter. Unless otherwise noted, the high byte of stat% is returned as 0.

Address Status Reek& Stat (Return) -Low Byte

BIT 7

6 5

2 1 0

X X

x LA TA X

Where

X This bit may be any value. CIC

Active Controller. If this bit is set to 1, then the KM48& ROM is a System Controller.

4-24 KM-488~ROM USER GUIDE

- STATUS (cont.)

Listener. If this bit is set to 1, then the KM&?&ROM is a Listener.

Talker. If this bit is set to 1, then the KM488-ROM is a Talker.

Interrout Status Reeister 1 Stat (Return) -Low Byte

BIT 7

6 5

4 3

2 1

X X

GET X

DEC

X X

Where

This bit may be any value.

GET

Group Execute Trigger. If this bit is set to 1, then a Group

Execute Trigger command was received while the KM488-

ROM was a device.

DEC

When this bit is set to 1, a Device Clear was received.

Interruvt Status Reeister 2 Stat (Return) -Low Byte

BIT 7

4 3

2 1 0

X SRQl LOK

REM

X X X ADSC

Where

X This bit may be any value. SRQI

When this bit is set to 1, it indicates SRQ was active. (Active

Controller mode only.)

LOK

When this bit is set to 1, the device was set to Local Lockout. (Device mode only.)

AEMC

When this bit is set to 1, the device was configured for remote operation. (Device mode only.)

ADSC

When this bit is set to 1, a change of the address status occurred (i.e., untalk to talk, device to active controller, etc.).

DMA Status Reeister Stat (Return) - Low Byte

BIT 7

5 4 3

2 1 0

X X

TC3

TC2 TCl X

NOTE: DMA Status Register: it is useful to check the status of this register when running DMA operations in

background mode. Where X

This bit may be any value.

PROGRAMMING IN BASICA OR GWBASIC

4-25

- STATUS (cont.)

TCl

When this bit is set to 1, it indicates that DMA channel 1 has reached terminal count.

TC2

When this bit is set to 1, it indicates that DMA channel 2 has reached terminal count.

TC3

When this bit is set to 1, it indicates that DMA channel 3 has reached terminal count.

Message Terminator #O-3: Contains First and Last bytes of the message

terminator. Input terminators are only one byte long and are contained in the Least Significant Byte. In the case of a two character Output Terminator, the Most Significant Byte of this parameter is the first

character sent.

DMA Timeout and I/O Timeout Parameters: Contains the value of the

desired parameter as an unsigned value in the low and high bytes of

stat%. The timeout value is expressed in milliseconds (0 to 65535).

notes The bits contained in the Interrupt Status 1 and 2 registers are extremely

volatile. When you read these registers, any bits which were set are

automatically cleared by the READ operation. This is extremely

important to note when reading Interrupt Status Register 1, as some of

the bits (not shown above) are used by various KM&X&ROM routines.

It may be possible to cause various KM-488-ROM routines to report a

timeout error if this register is read while the KM-488-ROM is addressed

to talk or listen.

- XMIT

purpose Sends GPIB commands and data from a string.

offset 3

usage . . .

x%xMIT-3

xx infoe = #v...s* xx stat% =

XXCALL XMIT (infos,*tat%)

alternate usage

CALL TRWS!4TT(info$,stat%)

4-26 KM-488-ROM USER GUIDE

- XMIT (cont.)

psmmeters infa$ is a STRING variable containing a series of GPIB commands and

data. Each item must be separated by one or more spaces.

Commands

can be in UPPER or lower case. The Transmit comman

ds are described

in Chapter 3. These commands include

CMD GTL

MTA SDC M

DATA GTLA MLA

SEC

DCL

IFC

PIT SPE l-2

END LISTEN

PPD SI’D T3

EOI LLO FPU

TALK UNL

GET LOC

RBN

TCT

UN-r

returns stat% is an INTEGER which describes the state of the transfer returned

after the call. The returned stat value can be interpreted as follows: Stat (Return) -Low Byte

BIT 7 6 5

4 3 2

1 0

Where

X May be any value. ADRS

Invalid GPIB address. If this bit is set to 1, then an invalid GPIB address was given.

NCTL Not a System Controller. If this bit is set to 1, it indicates

that the KM488-ROM tried to send GI’IB Bus Commands when it was not an Active Controller.

UNDF Undefined Command. If this bit is set to 1, the info string

contained an undefined command.

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

STR String Error. If this bit is set to one, then a quoted string,

END, or terminator was found without a DATA subcommand preceding it.

NT KM-H&ROM not a Talker. If this bit is set to a 1, it

indicates the routine was called before the KM-488-ROM was designated as a Talker.

SIX Syntax Error. If this bit is set to 1, a syntax error was found.

example This example illustrates one way to use the XMIT command with a

Keithley 1% Voltmeter. This meter is assigned GPIB address 7 and is configured to a 30 Volt DC range with 4 l/2 digit accuracy. The meter is also configured to take a new reading each time a Group Execute Trigger Bus command (GET) is received. It is assumed that the meter has been set to use a CR, LF, EOI (the default for Message Terminator I). The program then triggers the instrument to get the first reading, and makes it a talker and the KM&Xl-ROM a listener in order to get the first reading.

The device to receive the setup comman d string which must be sent to the meter contains the following device commands:

PROGRAMMING IN BASICA OR GWBASIC 4 - 27

XMIT (cont.) Ixl

Select DC Volts mode

Select 30 Volt range

Select 4 l/2 digit accuracy

Take one reading when GET received

X Execute the prior commands within the string The device to receive the setup command string must also be

programmed to assert the GPIB REN signal (This allows the meter to receive GPIB co

mmands.) and to LISTEN (This allows the device to receive the string.). The programming sequence used consists of the following:

Setting Remote Enable (RBN).

Setting all devices to UNTalk and UNListen.

Addressing the 196 to LISTEN.

Addressing the KM488-ROM to talk (My Talk Address).

Sending the Device-Dependent Commands as a string of DATA.

Sending the appropriate message terminator characters after the data.

Issuing the Group Execute Trigger bus command.

Unaddressing all devices.

Addressing the meter to TALK and the KM488-ROM to LISTEN (My

Listen Address) in preparation for receiving the latest reading.

- XMITA

pt~rpo~e Transmits data from an array.

offset 200

usage . .

xx XMITA = 200 xx ma*% = xxOf#% =

xx DIM

INFO% (n%) XI aount% - z*n% x1( term% = xx &at% = 0

xx OfS% = VARpTR(infO%(O))

xx GAIL XMITA(~sg%,of~%,oount%,tsnn%,stat%)

. . .

alternate usage

CALL TARRAY(~og%,of~%,aount%,tsna%, hat%)

4.20 KM-4t38-ROM USER GUIDE

- XMITA (cont.)

parameters seg% is an INTEGER representing the segment portion of the memory

address of the data. seg% is set to -1 to the BASICA data segment.

ofs% is an INTEGER representing the offset portion of the memory

address of the data. This is usually obtained using the VARM’R

function. The VARFTR function must be called immediately prior to the

XMITA function call and all variables used within the program must be

declared prior to the VARPTR function. The reason for this is that

BASICA can dynamically allocated storage space and if variables are

declared after the VARPTR call, there is a good possibility that the array

will be relocated and the data will be placed into the wrong location.

count% is an INTEGER containing thhe number of data bytes to be

transmitted. To send more than 32767 bytes, refer to Programming Note

4 in the beginning of this section.

term% is an INTEGER which selects the terminator to be used. This

byte is of the following format:

Term (Input Parameter) -Low Byte

BIT 7

5 4 3 2 1 0

STRM

TRMl

TRMO

X X

1 x 1: x

EOI

Where

X This bit may be any value. STRM Send Message Terminators. If this bit is set to 1, then the

message terminator(s) will bc sent at the end of the

transmission. Otherwise, they will not.

TRMI-0 Terminator Select. These two bits select the Output

Message Terminator to be used to signal the end of a

transmission. Available terminator selections are

TRMl TRMO TERMINATOR # DEFAULT

0 0 0 LF EOI 0 1 1 CR LF Ii01

CR EOI

1 1

LF CR Ii01

These terminators can be redefined by running the CONFIG program as described in Chapter 2.

EOI Asserts EOI. If this bit is set to 1, then EOI will be asserted

when the last byte is sent. Otherwise, EOI will not be

asserted.

returns stat% is an INTEGER describing the state of the transfer returned after

the call. The stat value is interpreted as follows:

Stat (Return) -Low Byte

BIT 7

6 5

1 0

0 0 0 TM0 1 0 1’ NT 1 0

PROGRAMMING IN BASlCA OR GWBASIC 4 - 29

- XMITA (cont.)

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

KM488-ROM not a Talker. If this bit is set to a 1, it indicates the routine was called before the KM488-ROM was designated as a Talker.

notes When calling XMITA, you must declare an integer array from which to

transmit data. Since each integer in BASICA uses 2 Bytes of memory, the total number of array locations allocated must be equal to or greater than

one half the total number of bytes to be received.

exmp/e This example illustrates the use of XMITA. It shows you how to

properly set-up an array from which to send the data. Note that the data is sent without a terminator or EOI asserted.

4-30

KM-4WROM USER GUIDE

Chapter 5

PROGRAMMING IN QUICKBASIC

While Chapter 3 gives a brief overview of the routines available for programming the KM488-ROM, this chapter gives instructions for calling the routines from QuickBASIC. The routines appear in alphabetical order and include a sample program for each.

5.1 GENERAL

Supported Versions

The Environment

QuickBASIC 4.0 and higher Before you begin to develop programs in QuickBASIC, several

files must be present in your working directory. Copy the following files from the KM-488-ROM disks to your working directory:

QUICKBASIC 4.0 QUICKBASIC 7.O(QBX)

\QB\KM488QB.B1

‘QBKM488QB.BI

KjBKh4488QB4.QLB

/QB\KM488QB7.QLB

KjBKM488QB4.LIB

‘QBKM488QB7.LIB

File Header

Be sure to include the following line within your program:

‘$INCLUDE: ‘km488qb’

Including of this file allows QuickBASIC to check that the correct number and type of parameters are specified for each routine called.

Once your QuickBASIC application program has been written, you will compile the program. Be sure to include full path names to the various library files where needed.

From within the QuickBASIC Environment

Be sure that the appropriate .QLB file KM488QB4.QLB or KhU38QB7.QLB) is located where QuickBASIC can find it. Then, invoke QuickBASIC by typing

FOR QUICKBASIC 4.0

FOR QUICKBASIC 7.O(QBX)

qb /Lkm48llqb4 yourprog

qb /um488qb7 yourprog

where yourprog is the name of your program.

PROGRAMMING IN QuickSASlC 5 - 1

Software

To create a Standalone Program

This process compiles the QuickBASIC source code and linka it to the QuickBASIC and KM-488ROM library files. This process is slightly different depending on the version of QuickBASIC used. (See your manual for specifics.) The following example shows you how to link the files in Version 4.0:

link yo”zprog,, ,baom45tkm4eeqb4;

where yourprog is the name of your program.

bcom4.5 is the QuickBASIC Runtime library name. km488qb4 is the linkable BASIC library file.

The KM-488~ROM firmware contains a number of configuration parameters that govern the default settings of the input and output message terminator settings, message timeout periods, and I/O port addresses. The default terminators are shown in

the following table. If these default values are unsatisfactory, they may be changed by calling either the INTBRM or OUTTERM routine.

The default DMA and I/O Timeouts are 10 seconds. These defaults may be altered by calling the DMATIMEOUT or IOTIMEOUT routine.

Default Temlnator Settlngs

TERM #

OUTPUT TERMINATOR INPUT TERMINATOR

LF EOI

CRLFEOI

CR EOI

, (comma)

LFCREOI : (semi-colon)

Programming Notes

1. Any parameters which appear as variables may also be

passed as constants.

2. Parameters which are also used to retorn values must be declared as variables.

3. Integer variable names end with a percent sign and integer constants do not contain a decimal point.

4. All integers are treated by the KM-488-ROM routines as unsigned values (0 to 65535). However, QuickBASIC treats them as signed magnitudes (-32768 to +32767). When you need to express a value which is greater than or equal to 32768, you will need to express it in one of two ways:

Convert it to a hexadecimal value. Be sure to prefix these values with &H when equating them to a variable name. Legal hexadecimal values range from 0 to &HFFFF and can be used to represent values from 0 to 65535.

Use unsigned values from 0 to 32767 as is, but for values of 32768 to 65535 subtract 65536.

5. Do not name any of your variables with the same name as

those assigned to the KM488-ROM routines.

5-2 KM-488~ROM USER GUIDE

5.2 DESCRIPTION FORMAT FOR ROUTINES

The format for each descriptions is as follows:

Pwtwse

usage

alternate usage

parameters

returns

notes

example

5.3 ROUTINES

purpose

usage

alternate usage

parameters

returns

example

. . . a brief description of the routine.

See Chapter 3 for more detailed

descriptions. . . . gives an example of usage for each routine and assumes the input

parameters are passed in as variables. These parameters can also be passed in directly. See the General Programming Notes for more information.

. . . lists alternate usage for the routine, if any.

Unless otherwise noted, the

alternate usage performs exactly the same function as the usage. . . . describes each of the input parameters. . . . describes any values returned by the routine. . . . lists any special programming considerations. . . . gives a programming example using the routine.

DMATIMEOUT

Sets the maximum length of time for a DMA transfer to complete before a timeout error is reported. (See RCVA and XMITA routine descriptions.)

CArtL DMATIMEOOT (time%, CALL SETTIMEOUTkhne%) NOTE: The alternate usage sets both the DMA and I/O Timeouts to the

specified value. time%

is an INTEGER which represents the timeout period to elapse during a DMA transfer. A DMA Timeout Error will be generated when the time to transfer (via DMA) an entire message exceeds the set DMA timeout value (time). time% can range from 0 to 65535 milliseconds and is internally rounded to the closest integer multiple of 55 milliseconds. For values greater than or equal to 32768, time must be represented differently. See Programming Note 4 at the begining of this section.

This example sets the DMA Timeout period to 5 seconds.

DMA

TIMEOUT (5000)

PROGRAMMING IN QuickBASIC

5-3

- ENTER

purpose Addresses a specified device to talk, the KM4!8-ROM to listen, and

receives data from the addressed device into a string.

usage . . .

'8etup an 80 ahar l tring

i&0$ - sPAcs$(50)

1 to rsooivs tho data

caIJ4 EUTER (info$,lmlg%,a&a%, *tat%)

parameters lnfo$ is a STRING which is to hold the receive data. The string must be

long

enough

to receive the expected number of characters.

This may be accomplished using the QuickBASIC SPACB$ function. For example, the line INFo$ = SPACE$(lOO) allocates a 100 character string for storing

data. Carriage returns and the message terminator character in the incoming data are ignored and not placed in received data.

a&% is an INTEGER containing the IEEE bus address of the device that the data is to be sent to and the terminator to be used. This byte is of the following format:

Adrs (Input Parameter) - Low Byte

BIT 7

5 4

TRMl

TRMO 0

ADR4 ADR3 ADR2

ADRI ADRO

Where

TRMl-0

ADR4-0

Terminator Select. These two bits select the Message Terminator to be used to signal the end of a transmission. Available terminator selections are

TRMl TRMO

TERMINATOR #

DEFAULT

0 0

0 1

1 CR

1 1

These terminators may be changed by the INTERM routine. The easiest way to specify an alternate terminator is to add

a factor to the GPIB address of the desired instrument which is specified within the ENTER call. The factors added for each terminator are as follows:

GPIB Address + 0 = Terminator 0 GPIB Address + 64 = Terminator 1 GPIB Address + 128 = Terminator 2 GPIB Address + 192 = Terminator 3

For example, if you wanted to receive a message using terminator 2 from a device at GPIB address 10, the value of adrs% supplied to ENTER would be 138 decimal (10 + 128).

GPIB Address. These five bits are used to represent the GPIB address of the device to which the data is to be sent. GPIB addresses can range from 0 to 30.

5-4 KM-468~ROM USER GUIDE

- ENTER (cont.)

returns Info8 is a STRING variable, up to 256 characters, which will contain the

received data. The length of the string must be long enough to receive the expected number of characters. Enter will terminate reception of data when: 1) the number of characters received exceeds the length of the string, 21 the specified terminator is received, or 31 any character is received with the EOI signal asserted. Carriage returns and the terminator character in the incoming data are ignored and not stored with the received data.

However, bytes other than the terminator which

are received with EOI asserted will be stored. leng%

is an INTEGER, less than or equal to 256, which indicates the actual number of bytes which were stored. This number does not include message termmator characters or carriage returns.

stat%

is an INTEGER which describes the state of the transfer returned after the call. If a stat value of 0 is returned, the transfer completed normally. Otherwise, the returned stat values for combination of) are interpreted as follows:

Stat (Return) -Low Byte

BIT 7

6 5

1 0

0 0 0

TM0 OVF NC ADRS

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

OVF

Overflow Error. If this bit is a 1, then the info string was filled, before a terminator character or EOI was detected.

NC KM-488ROM not an Active Controller. If this bit is set to a

1, it indicates the routine was called before the KM-488-

ROM was designated as an Active Controller.

ADRS

Invalid GPIB address. If this bit is set to 1, then an invalid GPIB address was given.

example In the following example, data is sent from two different instruments to

a KM-488-ROM. The KM-488ROM is acting as the System Controller and is assigned to GPIB address 0. One of the two instruments is a voltmeter, requiring a Carriage Return-Line Feed terminator combination (Term 11, assigned to GPIB address 7. The second instrument, located at GPIB address 10, requires a line feed (Term 01 as its terminator. The voltmeter is first sent a string of data which represents its instrument setup command. Then, when addressed to talk, it sends its most current reading to the KM-I88-ROM. The second instrument is instructed to send its status, when addressed to talk.

It is assumed that the string sent by both instruments is 25 characters or less. The string is printed out on the computer screen.

PROGRAMMING IN QuickBASiC

5 - 5

ENTER (cont.)

purpose

usage

alternate usage

parameters

INIT

Initializes the KM-488-ROM by assigning its GLIB address and

establishing it as a System Controller or Device.

CALL

INIT

(a&#%,m&%)

CALL INITIALINE (dr~%,m~&%)

adrs% is an INTEGER representing the IEEE bus address of the KM-488-

ROM. This is an integer from 0 to 30.

mode% is an INTEGER representing the operating mode of the KM-488ROM. These can be any of the following values:

Mode - Low Byte

BIT 7

5 4 3 2 1 0

X X

FAST

DEV X

Where

May be any value.

FAST

Handshake Speed. If this bit is set to 1, High Speed GPIB bus handshaking will be used(5OOns.). If it is set to 0, Low Speed GI’IB bus handshaking (2 s.) will be used. See Chapter 3 for more information regarding the handshake

Speed.

5-6

KM-466~ROM USER GUIDE

- INIT (cont.)

DEV

Device. If this bit is set to 1, then the KM488-ROM is acting as a Device. Otherwise, when this bit is set to 0, the KM48EROM is acting as a System Controller. When System Controller is selected, the GPIB IFC line is momentarily asserted.

returns None.

exampte This example initializes the KM-488-ROM as a System Controller with a

IEEE address of 0 with a High Speed Handshake.

CALL

IPIT (0.4)

- INTERM

purpose Changes the input message terminator settings.

usage

CALL ImmN(num%.tsrm%)

alternate usage

CALL sETTkmJTEos

(term%)

NOTE: The Alternate Syntax will only change the value of Input

Message Terminator 0.

parameters num% is an integer which selects the number of the receive message

terminator to be changed. This ranges from 0 to 3, where

IlUlN%

TERMINATOR #

DEFAULT

0 0

1 1

2 2 3 3

term%

is an integer representing the terminator byte to be programmed. This integer is the decimal or hex equivalent of the terminator’s ASCII representation. Hex equivalents must be preceded by &H. See Appendix A for ASCII Equivalents.

returns None.

eXamp/e

This example sets Input Terminator 3 to Line Feed (Hex A).

cJlLL

INTam4(3,CNA)

- IOTIMEOUT

purpose Changes the length of time to elapse before an I/O Timeout occurs.

usage . . .

GAIL

1oT1mE0uT

(tAIm%)

PROGRAMMING IN QuickBASIC

5 - 7

- IOTIMEOUT (cont.)

parameters time% is the time elapsed before a timeout error is reported. This

occurs if the time elapsed between the transfer of individual bytes exceeds the specified I/O Timeout period.

time% is between 045535 ms, internally rounded to the closest multiple of 55 ms. ‘Ike default is 10 seconds.

returns None.

eXampte This sets the I/O timeout to 1 second.

CALL IOTI~O'JT(1000)

- OUTTERM

purpose Changes the output message terminator sequences.

usage CALL

OuTTERU(n~%,~r*%,~i%,tnnl%,trm2%)

alternate usage

CAwl SSTOUTPUTSOS(tnnl%,tm2%)

NOTE: The Alternate Syntax will only change the value of Terminator 0, and will always assert EOI

upon

the transmission of the last character. In addition, a single character terminator is programmed by setting bTnz% to 0.

parameters num% is an INTEGER which selects the number of the transmit

message terminator to be changed. This ranges from 0 to 3, where:

num%

TERMINATOR #

DEFAULT

0 0

LF EOI

CRLFEOI

CREOI

LFCREOI

chars% is an INTEGER that selects the length of the transmit terminator. This is 0 if a l-character terminator is required or 1 for a 2-character terminator.

eoi% is an INTEGER that determines whether EOI is asserted when the last terminator byte is sent. If this bit is 1, EOI will be sent. If this bit is 0, EOI will not be sent.

&ml% is an INTEGER representing the first terminator byte to be sent; it is the decimal or hex equivalent of the terminator’s ASCII representation. Be sure to precede all hex values with &H. See Appendix A for ASCII Equivalents.

4~~2% is an INTEGER representing the second terminator byte ( in a 2.

byte terminator); it is the decimal or hex equivalent of the terminator’s

ASCII representation. Be sure to precede all hex values with &H. If a l-

byte terminator is programmed, trm2% may be any value.

returns None.

example This example sets Output Terminator 1 to Carriage Return, Line Feed,

EOI.

CALL 0UTTERM(1,1,1,CED,CHI)

5-8

KM-488-ROM

USER GUIDE

usage

parameters

returns

notes

Purpose

usage

alternate usage

PPOLL

Initiates a parallel poll. NOTE: Many GPIB devices do not support parallel polling. Check your

device’s documentation. CALL PRCLL

(ramp%)

None. reap%

is an INTEGER which will contain the received parallel poll

response. Before you call the PI’OLL routine, you must first configure the Parallel

Poll response of the device. To do this:

Address it to listen.

Send it a GI’IB Parallel Poll Configure (WC) command.

Send a Parallel Poll Enable byte using the KM-488-ROM XMIT command. (Use the mnemonic CMD followed by

nnn where mm

the decimal value of the Parallel Poll Enable byte.

The Parallel Poll Enable Byte is of the format OllOSPPP, where:

S is the parallel poll response value (0 or 1) that the device uses to

respond to the parallel poll when service is required. PPP is a 3-bit value which tells the device being configured which data

bit it should use as its parallel poll response (DIOI through DIOS). This example assumes that the KM488-ROM is connected to a Sorenson

HPD30-10 Power Supply. This device is located at GPIB address 1. It is also assumed that this device drives bit 4 of the Parallel Poll Response byte to a logic “1” when service is required. In order to retrieve this response, the device’s parallel poll response must be configured to respond in this manner. This is accomplished by using the KM-488ROM XMIT routine with the CMD command accompanied by the command byte 01101011(107).

cau hlit.(O,O)

RCV

Receives data into a string.

. . .

i&0$-SPACE8 (80)

'AlloLTatm l paaa ior roooivo* d&r

GAIL RCV(info$,tsrm%,r~lsn%,*t~t%)

1..

CALL ~~~(info$,rc"lur%,‘t.t$)

PROGRAMMING IN QuickBASIC

5 - 9

- RCV (cont.)

NOTE: The Alternate Syntax assumes the use of Input Message Terminator 0.

parameters

info$ is a STRING which will hold the received data. Prior to calling RCV, you must initialize a string which is long enough to receive the expected number of characters. This may be accomplished using the QuickBASIC SPACE$ function. For example, the line INFO8 = Sl’ACE$WC0 allocates a 100 character string for storing data. Carriage returns and the message terminator character in the incoming data are ignored and are not stored with the received data.

term% is an INTEGER containing the number of the IEEE bus terminator to be used, where:

term%

TERMINATOR # DEFAULT

1 CR

These terminators can be changed by calling the INTERM routine.

returns Mo$ is a STRING variable (up to 64 KBytesI which will contain the

received data. The length of the string must be long enough to receive the expected number of characters. RCV will terminate reception of data when: 1) the number of characters received exceeds the length of the string, 21 a terminator is received, or 3) any character is received with the EOI signal asserted. Carriage returns and the message terminator character in the incoming data are ignored and not stored with the received data.

rcvlen% is an INTEGER which indicates the actual number of bytes which were received and stored.

stat% is an INTEGER which describes the state of the transfer returned after the call. The returned stat values are interpreted as follows:

Stat (Return) - Low Byte

BIT 7

5 4 3

2 1 0

0 0

0 TM0

OVF NL 0

TM0

Ttmeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

OVF

Overflow Error. If this bit is a 1, then the info string was filled, before a terminator character or EOI was detected.

NL KM-488-ROM not a Listener. If this bit is set to a 1, it

indicates the RCV was called before the KM488-ROM was designated as a Listener.

notes The KM4WROM must be addressed to listen and another device

addressed to talk before calling RCV.

J-10

KM-W&ROM USER GUIDE

- RCV (cont.)

example The following example shows how the RCV routine might be used

together with the XMIT routine to receive data. It demonstrates a method of triggering the KeithIey 196 voltmeter to take a reading using the XMIT command and then receiving the meter reading using the RCV command. It is assumed that the meter reading returned will fit into a string of 25 characters. This example also assumes that the KM-488ROM has been configured to use Transmit Message terminator 1 as a Carriage Return-Line Feed combination.

Purpose

usage

RCVA

Receives data into an array. This routine may also be used to receive data via DMA (See SETDMA.)

. . .

DIM in&t*% (1000)

'allooats 1000 .rray looations

maxlen% - 2000 Cw

W”A(in&t&(O)

,mulsn%,tsrm%,r~vlon$,.t~t%)

. . .

alternate usage

paremeters

CALL stAmAY(in&ta%, msrlsn%,ravlm%,*tat%)

NOTE: The Alternate Syntax assumes the use of EOI as a terminator.

term%

is an INTEGER which selects the type of terminator to be used.

This integer is interpreted according to the following format: Term (Input Parameter) -Low Byte

BIT 7

6 5

2 1

X X X

STRM

TFiMl TRMO

Where

X May be any value.

STRM

Enable/Disable String Message Terminators. If this bit is 1,

Message Terminator Character will be used to detect the end of reception. If this bit is 0, a Message Terminator Character will not be used.

PROGRAMMING IN QuickBASIC 5-11

RCVA (cont.)

TRMl-0

Terminator Select. These two bits select the Input Message Terminator to be used to signal the end of a transmission.

(The STRM bit must be set to 1.) Available terminator selections are

TRMl TRMO

TERMINATOR #

DEFAULT

0 0

1 1 CR

1 0

The values for these terminators can be changed by calling

the INTERM routine.

maxlen% is an integer which specifies the maximum number of data bytes which can be received. When you want to receive more than 32767 bytes, use the technique outlined in Programming Note 4 presented at the beginning of this section. maxlen% must be less than or equal to twice the total number of bytes allocated in the indata% array or a program crash may occur.

refurfls

indata% is an array which will contain the received data. All characters received are stored.

rcvlen% is an integer which will contain the actual number of data bytes which were received. Note that half this many array locations will contain data. To specify more than 32767 bytes, use the technique outlined in Programming Note 4 presented at the beginning of this section.

stat% is an integer describing the state of the transfer returned after the call. The RCVA routine returns three status bits within the stat% variable. The TM0 bit is used to signal a timeout error. The REOI bit signals that the routine returned because the terminator was detected (if enabled), or EOI was received. The NL bit is set if the RCVA routine was called and the card was not addressed to listen. Unlike other KM-488ROM routines, it is possible to return a non-zero status when the call was completed successfully.

Stat (Return) - Low Byte

BIT 7

6 5

3 2

REOI 0

TM0 0

NL 0

Where

REOI Reason for RCVA Termination. If this bit is a 1, then RCVA

routine ceased because an EOI or terminator character was received. If this bit is a 0, then the RCVA was terminated

because an error occurred or the maximum byte count was

reached.

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a

Timeout Error occurred.

5.12 KM-488~ROM USER GUIDE

- RCVA (cont.)

NL KM488-ROM not a Listener. If this bit is set to a 1, it

indicates the RCVA was called before the Kh4488-ROM was designated as a Listener.

/10fe8

The KM488-ROM must be addressed to listen before calling this routine.

example Refer to the XMITA example.

- SEND

purpose Addresses a specified device to listen, the KM488-ROM to talk, and

sends data from a string.

usage

info$

- “d&a to be trmmdttd”

CAT& sm (a&*%,info$,*t~tu~%)

parameters adrs% is an INTEGER containing the IEEE bus address of the device

that the data is to be sent to and the terminator to be used. This byte is of the following format:

Adrs (Input Parameter) -Low Byte

BIT 7

6 5

4 3 2

TRMI TRMO 0 ADR4 ADR3 ADR2

ADRl ADRO

Where

TRMl-0 Terminator Select. These two bits select the Input Message

Terminator to be used to signal the end of a transmission. Available terminator s&ctions are

TRMl TRMO

TERMINATOR # DEFAULT

0 0 0

0 1 1 CR

0 2

1 1

The values for these terminators can be changed by running the CONFIG program as described in Chapter 2.

The easiest way to specify an alternate terminator is to add a factor to the GPIB address of the desired instrument which is specified within the SEND call. The factors added for each terminator are as follows:

GPIB Address + 0 = Terminator 0 GPIB Address + 64 = Terminator 1 GPIB Address + 128 = Terminator 2 GPIB Address + 192 = Terminator 3

For example, if you wanted to send a message using message terminator 2 to a device at GPIB address 10, the value of adrs% supplied to SEND would be 138 decimal (10 + 128).

PROGRAMMING IN QuickBASIC

5-13

- SEND (cont.)

AOFM-0

GPIB Address. These five bits are used to represent the GPIB address of the device to which the data is to be sent. GPIB addresses can range from 0 to 30.

ix&$ is a STRING (256 chars max.) containing the data to be sent.

returns stat% is an INTEGER describing the state of the transfer returned after

the call. The returned stat values (or combination of) are interpreted as follows:

Stat (Return) -Low Byte

BIT 7 6

5 4 3 2

1 0

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1,

then a

Timeout Error occurred.

Not Active Controller. If this bit is a 1, then the SEND routine was called when the KM488-ROM was not an Active Controller.

ADRS Invalid Address. If this bit is set to a 1, an invalid IEEE488

device address was given.

examp/e This example shows how to send data from a KM488-ROM to a device.

The KM488-ROM is initialized as a System Controller located at GPIB address 10. The KM488-ROM uses high-speed handshaking. The data

(a device setup string) is sent to a device located at GPIB address 12.

‘~I”cLuDs:‘sn1*8QB’

CALL INTT,lll,1,

an alternative, the following sequence can be used:

- SETBOARD

purpose In a multiple board system, identifies the KM488-ROM to be

programmed.

usage cam kmmmto

(board%)

alternate usage

CALL BOARDSELECT (board%)

5-14

KM-488-ROM USER GUIDE

parameters

returns

notes

example

wwse

usage

alternate usage

parameters

returns

notes

SETBOARD (cont.)

board% is an INTEGER between 0 and 3 which represents the board to be programmed. Note that up to four boards can be installed in any one system. The board% “number” is associated with the base address of its

I/O port. None. You must assign a board “number” for every KM438-ROM in the system

before calling the SETBOARD routine. Board numbers are assigned using the SETPORT routine.

Each board must be must be initialized independently by calling the lNIT routine. You must do this the first time a given board is selected, before any other operations are conducted on that board.

Once a board has been selected using SETBOARD, all further I/O operations will be performed on that board until the

SETBOARD is

executed. This example line selects board “2” for communication.

SETBOXD(2)

SETDMA

NOTE: DMA allows maximum data transfer rates

in excess of

100 kilobytes per second. However, the actual data rates are limited by the rates at which other devices connected to the bus can send or receive data. These rates are governed automatically by the GPIB handshaking signals.

Allows the use of DMA in conjunction with the XMITA and RCVA routines.

CALL 8ETDI(R(ohuursl%) CAL& Eamcamm(ahMnSl%)

channel% is an INTEGER which specifies the DMA channel to be used for the data transfer. channel% can be from 1 to 3, where:

1 = Use DMA channel 1. 2 = Use DMA channel 2. 3 = Use DMA channel 3.

To disable DMA. set channel% to a value other than 1,2 or 3. None. The DMA hardware jumpers must be properly set for the DMA channel

selected by SETDMA. Note that the default setting for the jumpers is

DMA DISABLED. The jumpers are further described in Chapter 2. When SETDMA is called to enable the use of DMA, each call to the

XMlTA and RCVA routines that follows will use DMA to accomplish the

transfer until SETDMA is called with a parameter outside the range of l-

PROGRAMMING IN QuickBASIC

5-15

- SETDMA (cont.)

example This example specifies that DMA transfers are to take place using DMA

channel 1 and then DMA is disabled.

CALL SETDIdA(1) 'enabloa dnu trurafsra via ahannol 1

SETINT

purpose Sets the KM-488-ROM’s interrupt enable bits.

usage CALL

SETIm

(intval%)

parameters

intval% is an INTEGER containing the address and value of the Interrupt Mask Register. This is interpreted as follows:

INTVAL (Input) - High Byte

BIT 7 6 5 4

2 1

X X

X X ADRS

Where

X May be any value.

ADRS

If thls bit is set to 0, bits 0 through 7 will be written to Interrupt Mask 1. If this bit

is set to 1, bits 0 through 7 will

be written to Interrupt Mask 2.

INTBRRUI’T MASK 1

INTVAL (Input) -Low Byte (ADRS = 01

BIT 7 6 5 4

2 1

0 0 GET 0

DEC

0 0 0

Where

GET

DEC

When thls bit is set to 1, an interrupt will be generated when a KM438-ROM acting as a device received a GPIB GET (Group Execute Trlgge;) command while addressed to listen.

When this bit is set to 1, an interrupt is generated when a Device Clear is received.

INTBRRUIT

MASK 2

INTVAL (Input) -Low Byte (ADRS = 1)

BIT 7 6

5 4 3

2 1

Stml

0 0 0

LOKC REMC ADSC

5-16 KM-488~ROM USER GUIDE

- SETINT (cont.)

Where

SRQI

When thls bit is set to 1, an interrupt is generated when SRQ is received.

LOKC

When this bit is set to 1, an interrupt is generated when the state of the Local Lockout bit changes.

REMC

When this bit is set to 1, an interrupt is generated when the state of the Local/Remote bit changes.

ADSC

When this bit is set to 1, an interrupt is generated when the state of the LA, TA, or CIC bits within the address status

returns None.

notes Be certain to assign the KM488-ROM to an interrupt level before using

this routine. Interrupt Levels are assigned by means of a jumper on the

KM-488-ROM board. This

jumper is

described in detail in Chapter 2.

You must set-up an interrupt handling routine within the QuickBASIC

program to deal with the interrupt condition.

example Thls example enables the KM488-ROM to generate an interrupt

when

SRQ is received.

Cw SETINT(&EltO)

- SETPORT

purp088

This routine is used to alter the range of addresses used by the KM-488ROM’s I/O port. In a multiple board environment, it is also used to

associate a given range of I/O addresses with a board number.

usage

CA&L

SETRCRT

(board%, ioport%)

PeJZVrIeterS board% is an INTEGER between 0 and 3 which represents the board to

be programmed. Note that up to four boards can be installed in any one system. The board% “number” is associated with the base address of its I/O ports.

ioport%

is an INTEGER representing the I/O Base Address of the KM488-ROM. The default Base Address is 288 Hex. The Base Address selected must match the one selected by the Base Address Switch on the KM-488-ROM. (See Chapter 2 for

information.)

returns

None.

notes When multiple boards are used, each board must have its own unique

base address. Any Base Address can be assigned to any board number, provided that none of the base addresses overlap.

example This line assigns Board 0 an I/O Base Address of 300h.

*stpoa

(0, CE300)

PROGRAMMING IN QuickBASIC

5-17

- SETSPOLL

piNpOSe

Defines the Serial Poll Response of a KM-N+ROM acting as a device (non-Controller).

usage

CALL

BETSPOIL

(rasp%)

fXtrar#re(efS

reap% is an INTEGER describing the serial poll response and the state of the SRQ bit. This byte is of the following format:

Resp% (Input) - Low Byte

BIT 7 6

5 4 3 2

SPR6 RSV SPR6 SPR5

SPR4

SPR3

SPR2

SPRl

Where

SPRl-6

Bits 1 through 8 of this device’s Serial Poll Response Byte.

Ftsv If this bit is 1, SRQ will be asserted to request servicing.

Otherwise, SRQ will not be asserted.

returns None.

oXample

This example illustrates a common use of SETSPOLL.

req.% = 0

purpo=

usage

parameters

returns

SPOLL

Performs a serial poll of the specified device.

CALL sPOLL(.dr.%,re.p%,.t*+%)

adrs% is an INTEGER containing the IEEE bus address of the device that is to be serial polled. This can range from 0 to 30.

the manufacturer’s operator’s manual for more information. stat% is an INTEGER describing the state of the transfer returned after

the call. The stat value is interpreted as follows:

Stat (Return) -Low Byte

BIT

7 6

5 4

3 2

1 0

0 0

TM0 0

NC ADR

6-16

KM-466~ROM USER GUIDE

- SPOLL (cont.)

Where

TM0

Indicates whether a Timeout Error occurred during data transfer. If a 1, then a Timeout Error occurred.

KM4?8-ROM not a Controller. If set to a 1, it indicates the routine was called before the KM-488-ROM was designated as an Active Controller.

ADR Invalid GPIB Address. If this bit is set to 1, an invalid GPIB

address was provided.

&%3m~/e This example illustrates a simple serial poll of a device located at GPIB

address 10.

- SRQ purpose Detects the presence of the GPIB SRQ signal.

usage IP (SRW) TBeU

parameters None.

returns The SRQ function returns a 0 or FALSE when not present, or a 1 or TRUE

when present.

notes The value returned by SRQ is generally used within a conditional branch

in an application program. Note that after obtaining a TRUE response from SRQ, SRQ response is

reset to FALSE even if the SRQ line is still active. In order to reset the SRQ response to TRUE, you must serial poll at least one device with a requesting service. Conducting a serial poll on a device requesting service resets its SRQ line. Then, if other devices were simultaneously asserting SRQ, the output of SRQ will be reset to TRUE. Otherwise, SRQ becomes TRUE on the next SRQ assertion.

examp/e This example assumes that the KM-488-ROM is connected to an

instrument located at GPIB address 1 and capable of requesting service via SRQ. When SRQ is detected, the SPOLL function is called and the serial poll response of the device is printed to the computer screen.

‘$IwCLmE:

‘km488qb.k.i

IF moo) THRW

PROGRAMMING IN QuickBASIC 5-19

- STATUS

purpose Returns the current setting of the requested status parameter.

usage

CAL&

STATUS

(rep%, .t.t%)

parameters

reg% is an INTEGER containing the address of the register or

configuration parameter to be queried. reg% must be passed as a variable. This value corresponds to a 4-bit field which specifies the status register or configuration parameter to be read.

The format of the

reg% byte is as follows: Reg (input) - Low Byte

BIT 7

5 4

X X ADR3 ADR2 ADRl ADRO

Where

May be any value.

ADRS0

REGISTER/PARAMETER SELECT. This is a 4-bit field which specifies the status register or configuration parameter to be read. Registers and parameters are selected as follows:

ADRS ADIU ADRI

ADRO REGlS”?RmARAMRTER

returns

reg% -When STATUS obtains the value of one of the four transmit message terminators, this variable will contain two flag bits which determine the length of the terminator and whether or not EOI is asserted with the last byte. When obtaining other parameters, reg% will retain its input value.

Reg (Return) - Low Byte

BIT 7

6 4 3

1 0

0 0

0 0 0 LEN

EOI

5-20

KM-466-ROM USER GUIDE

- STATUS (cont.)

Where

LEN

Terminator Length. If this bit is set to 0, then the terminator

is one byte long. If this bit is set to 1, then the terminator is two bytes long.

EOI

If this bit is set to 1, EOI is asserted when the last terminator byte is sent. Otherwise, EOI is not asserted.

Address Status Register Stat (Return) -Low Byte

BIT 7 6

6 4 3

2 1 0

Where

X cc

This bit may be any value.

Active Controller. If this bit is set to 1, then the KM488-

ROM is a System Controller.

Listener. If this bit is set to 1, then the KM-4&3-ROM is a

Listener.

Talker. If this bit is set to 1,

then

the KM-488-ROM is a

Talker.

InterruDt Status Reeister 1 Stat (Return) -Low Byte

BIT 7 6

6 4 3

2 1 0

Where

X This bit may be any value.

GET

Group Execute Trigger. If this bit is set to 1, then a Group Execute Trigger comman

d was received while the KM-488-

ROM was a device.

DEC

When this bit is set to 1, a Device Clear was received.

Interruot Status Resister 2 Stat (Retorn) - Low Byte

BIT 7 6

6 4

1 0

X SRQl LOK

REM X

X ADSC

Where

This bit may be any value.

PROGRAMMING IN QuickBASIC 6-21

- STATUS (cont.)

SRQI

When this bit is set to 1, it indicates SRQ was active. (Active Controller mode only.)

LOK

When this bit is set to 1, the device was set to Local Lockout. (Device mode only.)

REM

When this bit is set to 1, the device was configured for remote operation. (Device mode only.)

ADSC

When this bit is set to 1, a change of the address status occurred (i.e., untalk to talk, device to active controller, etc.).

Transmit and Receive Messave Terminator #l-4. Contains First and Last bytes of the message terminator. Input Terminators and Single Character Output Terminators are contained in the Least Significant Byte. In the case of a two character Output Terminator, the Most Significant Byte of this parameter is the first character sent.

DMA Timeout and I/O Timeout Parameters. Contains the value of the

desired parameter as an unsigned value in the low and high bytes of

stat%. The timeout value is expressed in milliseconds (065535).

notes The bits contained in the Interrupt Status 1 and 2 registers are extremely

volatile. When you read these registers, any bits which were set are automatically cleared by the READ operation. This is extremely important to note when reading Interrupt Status Register 1, as some of

the bits (not shown above) are used by various KM-@&ROM routines. It may be possible to cause various KM-488-ROM routines to report a timeout error if this register is read at while the KM-488-ROM is addressed to talk or listen.

example This example illustrates a possible use for the STATUS routine.

re@ml : ‘f.t.5 - 0 CALL sT*r”s,reg%,.tat%,

- XMIT

purpose Sends GPIB comman

ds and data from a string.

usage CA?& IDlIT (info$, *tat%)

pammeters Info.$ is a STRING variable containing a series of GPIB commands and

data. Each item must separated by one or more spaces.

All the

available co

mmands are described in Chapter 3. These commands

include

5-22 KM-48%ROM USER GUIDE

- XMIT (cont.)

parameters Info.9 is a STRING variable containing a series of GPIB commands and

data. Each item must be separated by one or more spaces.

Commands

can be in UPPER or lower case. The Transmit commands are described in Chapter 3. These comman

ds include

CMD GTL MTA SDC To

DATA

GTLA

MLA SEC Tl DCL IFC FTC WE Tz END LISTEN

PPD

SPD T3

EOI LLO PPU

TALK UNL

GET LOC REN TCT UNT

returns

stat% is an INTEGER which describes the state of the transfer returned after the call. The returned stat value can be interpreted as follows:

Stat (Return) -Low Byte

BIT 7 6

4 3

1 0

X ADRS NCTL UNDF TM0 STR NT STX

ADRS

May be any value.

NCTL

Invalid GPIB address. If this bit is set to 1, then an invalid GPIB address was given.

Not a System Controller.

If this bit is set to 1, it indicates that the KM488-ROM tried to send GPIB Bus Commands when it was not an Active Controller.

UNDF

Undefined Command. If this bit is set to 1, the info string contained an undefined command.

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

STR

String Error. If this bit is set to one, then a quoted string, END, or terminator was found without a DATA subcommand preceding it.

NT KM-488-ROM not a Talker. If this bit is set to a 1, it

indicates the routine was called before the KM-488-ROM

was designated as a Talker.

STX Syntax Error. If this bit is set to 1, a syntax error was found.

This example illustrates one way to use the XMIT command with a Keithley 196 Voltmeter. This meter is assigned GPIB address 7 and is configured to a 30 Volt DC

range

with 4 l/2 digit accuracy. The meter is

also configured to take a new reading each time a Group Execute Trigger Bus command (GET) is received.

It is assumed that the meter has been set to use a CR, LF, EOI (the default for Message Terminator 1). The program then triggers the instrument to get the first reading, and makes it a talker and the KM-488-ROM a listener in order to get the first reading.

The device to receive the setup command string which must be sent to the meter contains the following device commands:

PROGRAMMING IN QuickBASIC

5 - 23

XMIT (cont.)

FO Select DC Volts mode R3 Select 30 Volt range Sl Select 4 l/2 digit accuracy T3

Take one reading when GET received

Execute the prior commands within the string

The device to receive the setup command string must also be programmed to assert the GPIB REN signal (This allows the meter to

receive GLIB commands.) and to LISTEN (This allows the device to receive the string.). The programming sequence used consists of the

following:

Setting Remote Enable (REN).

Setting all devices to UNTalk and UNListen.

Addressing the 196 to LISTEN.

Addressing the KM&&&ROM to talk (My Talk Address).

Sending the Device-Dependent Commands as a string of DATA.

Sending the appropriate message terminator characters after the data.

Issuing the Group Execute Trigger bus command.

Unaddressing all devices.

Addressing the meter to TALK and the KM-488-ROM to LISTEN (My

Listen Address) in preparation for receiving the latest reading.

- XMITA

purpose Sends data from an array.

usage

CALL lMITA(out&t%(O),aount%,tom%,~tat%)

alternate usage

TARRAY(acmnt%,tsrm%,~tat%)

parametsrs

outdat% is an INTEGER array containing the data to be sent. count% is an INTEGER containing the number of data bytes to be

transmitted. NOTE: In BASIC, when you want to send more than 32767

bytes, you will have to assign the value to count% in hex.

term% is an INTEGER that describes what sort of terminator should be used. This byte is of the following format:

Term (Input Parameter) -Low Byte

BIT 7

4 3

2 1

STRM

TRMl

TRMO X

X EOI

Where X This bit may be any value.

5-24 KM-4%ROM USER GUIDE

XMITA (cont.)

STRM Send Message Terminators. If this bit is set to 1, then the

message terminator(s) will be sent at the end of the transmission. Otherwise, they will not.

TRMl-0 Terminator Select. These two bits select the Output

Message Terminator to be used to signal the end of a transmission. Available terminator selections are

TRMI TRMO TERMINATOR #

DEFAULT

0 0

LF EOI

1 1 CR LF EOI

1 0

CR EOI

LF CR EOI

These terminators can be redefined by running the CONFIG program as described in Chapter 2.

EOI

Asserts EOI. If this bit is set to 1, then EOI will be asserted when the last byte is sent. Otherwise, EOI will not be asserted.

returns

stat% is an INTEGER describing the state of the transfer returned after

the call. The stat value is interpreted as follows: Stat (Return) - Low Byte

BIT 7 6 6

Where

TM0

Timeout Error. Indicates whether or not a Timeout Error occurred during data transfer. If this bit is a 1, then a Timeout Error occurred.

KM-488-ROM not a Talker. If this bit is set to a 1, it indicates the routine was called before the KM-488-ROM

was designated as a Talker.

example This example demonstrates use of SEND, XMITA, and RCVA to send

and retrieve waveform data from a GPIB oscilloscope. The scope expects data points to be sent with the most significant byte first. Thus, the data

bytes to be sent must be byte-swapped prior to sending them.

DSCLARB SW s*e.payt~~ (88) DSCLAm 80s Di.playmerr mxSt.e.t.%, srrorstr*,

DIM X%WZO, Y%(1024), 2%(1024), S%WOO) CLS : RBY on: coI,oa 7, 0

CaLI, INIT10,O) 'KM-488-ROH ia system oontroller nt OPIB ndrs 0 SCOPBP - 16

‘Saope l t a&x 16

PaINT ‘~Tlln?cArJZTNO SCOPP”: PaINT

PROGRAMMING IN QuickBASIC

5-25

- XMITA (cont.)

5-26 KM-488-ROM USER GUlDE

XMITA (cont.)

cm8 =

“EICDG w*m : BIWARY”

CALL SmD(SCGPB%, me, BmG%)

IB (HAG% 0 0, TEEN CALL Di~playm4errLFLaG%, CUDS)

am6 =

"OOTPDT mm."

CALL sBND,SCOPE%, aAD*, BL?.G%)

TB (SLAG0 <> 0) THBN CALL Di‘pl*yIG4err@wbG%, cMD$)

CMD8 -

"CVRVE 1" 'Ask for d*ta to be returned

CALL ssND,SCOPB%, aloe, BLaG%, IB (mAG% <> 0) TERN c?ALL DispPdymerr,yIAG%, Cl.m$)

CnDg = "lY.m 'I + STRB,SCOPS%, + aa PaA"

CALL xt4Ir(cMD6, mAG%,

'setup for saope to send data

IF (BxAG% <> 0) lwzN CALL DiaplaylQberr,BLAG%, adD$)

CGrmT%=7: IA-0

CGrmTP - 2050:

L% = 0 CALL RcvA(s%(ol, comT6, 0, 1%. SLAG%) 'D.tA reaeivec3 10 WAG% 0 0) TBBN CAL& Di.splayIWerr(BIAG%, CMO$)

IF L% <> (2 + N”KRW% l 2) TRE” GOT0 2080

FOR 1% = 1 TO 1024

se = -8 (9% (1%) I CAT& sr.pRyts. (MS) Y%(l% - 1) = vAL(E@) IP x%(1% - 1) - %(I% - 1) TEE" PRINT ".": ELSE PRINT I'*";

mm 1%

PROGRAMMING IN QuickBASIC 5-27

- XMITA (cont.) PRINT

888P% = 0 CALL SPOLL(BCGPE%, PaSP%, mAG%) PRINT “SPOLL. = “;

HBx$,RBSP% AND 255,

1% = LE”,B$) IB 1% - 1 TED%" B$ - "000" + B$ IB 1% = 2 TBXN B$ = "00" + B$ TB I.% = 3 THEN B$ = "0" + B$

LSS$ = RIGer$(s$, 2) Ksae = =wf$(B$. 2)

se = "LB" + LSB$ + WBS 'hap bytes

5-20 KM-488-ROM USER GUIDE

Chapter 6

PROGRAMMING IN TURBO PASCAL

While Chapter 3 gives a brief overview of the routines available for programming the KM48SROM, this chapter gives instructions for calling the routines from TURBO PASCAL. The routines appear in alphabetical order and include a sample program for each.

6.1 GENERAL

TURBO PASCAL direct support is currently offered for versions 4.0 and 5.0. The interface for TURBO PASCAL includes four different files, as follows:

KM488PAS.TPU “UNIT” file for use with Borland TURBO PASCAL version 5.0.

KM488P4.TPU “UNIT’ file for use with Borland TURBO PASCAL version 4.0.

KM488PASPAS Source file to be used for m-building TURBO Pascal “UNfT” file.

KM488PAS.OBJ Object code file to be used for re-building TURBO Pascal “UNIT” file.

The files KM488PASPAS and KM488I’LB.OBJ can be used to create a new “unit” file should you need to.

Supported Versions

The Envtronment

Turbo PASCAL versions 4.0,5.0 and higher. Before you begin to develop programs in TURBO PASCAL,

several files must be present in your working directory. Copy the appropriate files from the KM48EROM Disks to your working directory:

TURBO PASCAL 4.0 TURBO PASCAL 5.0

\turbopas~488p4.tpu IntrbopasUtm488pas.tpu

NOTE: km488p4.pas must be renamed km488pas.tpu.

File Header

Compiling

Software

Your application program can be compiled in the usual fashion. Be sure to include the following line in your program:

USES hm6pas; The KM-488-ROM firmware contains a number of configuration

parameters which govern the default settings of the input and output message terminator settings, message timeout periods,

PROGRAMMING IN TURBO PASCAL 6 - 1

and I/O port addresses. The default terminators are shown in Table 4-3. If these default values are unsatisfactory, they may be changed by calling either the INTERM or OUTTERM routine.

The default DMA and I/O Timeouts are 10 seconds. These

defaults may be altered by calling the DMATIMEOUT or

IOTIMEOUT routine.

Default Termlnator Settings

TERM # OUTPUT TERMINATOR INPUT TERMINATOR

LF EOI

1 CR LF’ EOI

CR EOI , (comma)

LF CR EOI

: (semi-colon)

1. Any arguments which appear as variables may also be passed

as constants.

2. Parameters which are also used to return values must be declared as variables.

3. Any of the KM4WROM routines which are used to receive data require that a named string or array be declared to store the received data. The length of the string or size of the array should be sufficient to store the number of bytes that are expected. In addition, these routines require a parameter which specifies the maximum number of bytes to be received. It is extremely important that the amount of storage space allocated is at least as great as this maximum length parameter. Otherwise, data may be stored into memory which has been allocated for use by other parts of your program, or for use by DOS. This could lead to

erroneous operation and possibly a system crash.

4. In TURBO Pascal, strings are actually a special type of character array. The first byte of the array is used to store the number of bytes contained within the string. Hence, strings may range from 0 to 255 bytes in length and the KM&B-ROM

routines which pass data to or from strings are limited to 255 bytes maximum.

5. Do not name the variables in your application program with the same name as any of the KM&?&ROM routines.

6. Do not assign a program name which is the same name as any

of the KM-48&ROM routines.

6.2 DESCRIPTION FORMAT FOR ROUTINES

The format for each descriptions is as follows:

purpose a brief description of the routine. See Chapter 3 for more detailed

descriptions.

usage

. gives an example of usage for each routine and assumes the input parameters are passed in as variables. These parameters can also be passed in directly. See the General Programming Notes for more

6-2

KM-488~ROM USER GUIDE

Keithley KM-488-ROM User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual