Black Box IC026A-R2, IC026AE-R2 3.3 Serial Port Settings

16

RS-232↔IEEE 488 INTERFACE CONVERTER

Note that the interface converter comes configured as an IEEE controller. In

this mode, the interface converter is designed to allow an RS-232 computer to

communicate with an IEEE peripheral such as a plotter. This controller mode

is described in detail in Chapter 4.

The interface converter may also be configured as an IEEE peripheral. As an

IEEE peripheral, it allows an IEEE controller to communicate with an RS-232

device. The peripheral mode of operation is described in detail in Chapter 5.

To modify any of these defaults, follow this simple procedure:

1. Disconnect the power supply from the AC line and from the interface. Also

disconnect any IEEE or serial cables.

WARNING

Never open the interface converter’s case while it is connected to the AC

line. Failure to observe this warning may result in equipment failure,

personal injury, or death.

2. Place the interface converter upside down on a flat surface. Remove the

four screws located near the rubber feet.

3. Return the interface converter to the upright position and carefully remove

the top cover.

4. Change whichever DIP-switch settings you need to change.

5. When you have made all your changes, reverse this procedure to

reassemble the interface converter.

3.3 Serial Port Settings

The first parameters to configure are those that correspond to the RS-232

port. These include baud rate, word length, number of stop bits, parity

selection and type of RS-232 handshake. Each of these are described in

the following sections.

3.3.1 S

ERIAL

B

AUD

R

ATE

The “baud rate” is the number of serial data bits per second transferred into

and out of the RS-232 interface. SW1-1 through SW1-4 determine the serial

baud rate. The factory-default baud rate is 9600 baud. Baud rates may be

selected from 110 to 57,600 baud. Refer to the following diagram for specific

baud rates.

Contents

Main RS-232IEEE 488 INTERFACE CONVERTER EUROPEAN UNION DECLARATION OF CONFORMITY WARNING! Failure to follow these directives voids emission and immunity compliance. Page Page Page CONTENTS Contents RS-232IEEE 488 INTERFACE CONVERTER CONTENTS 1. Specifications WARNING! CHAPTER 1: Specifications CAUTION 2. Introduction 2.1 Description 2.2 Abbreviations CHAPTER 2: Introduction 3. Getting Started 3.1 Inspection 3.2 Configuration Figure 3-1. Factory-Default Settings. SW3 SW2 SW1 3.3 Serial Port Settings Figure 3-2. Switch SW1: Selecting the Serial Baud Rate. Figure 3-3. Switch SW1: Selecting the Serial Word Length (Data Bits). Figure 3-4. Switch SW1: Selecting the Serial Stop Bits. Figure 3-5. Switch SW2: Selecting the Serial Parity. Figure 3-6. Switch SW2: Enabling or Disabling Echo. Figure 3-7. Switch SW1: Selecting the Serial Handshake. 3.4 Selecting Terminator Substitution Figure 3-8. Switch SW2: Selecting the Serial Terminator. Figure 3-9. Switch SW3: Selecting the IEEE Bus Terminator. 3.5 Selecting the Mode Figure 3-10. Switch SW2: Selecting the Mode. 3.6 Selecting the IEEE Address Figure 3-11. Switch SW3: Selecting the IEEE Address. 3.7 Feature Selections Figure 3-12. Switch SW1: Enabling or Disabling Talk Back on Terminator in Controller Mode. Figure 3-13. Switch SW2: Enabling or Disabling Talk Back on Timeout in Controller Mode. Figure 3-14. Switch SW1: Enabling or Disabling SRQ on Last Serial Terminator in Peripheral Mode. 3.8 Serial Interface Figure 3-15. Selecting RS-232 or RS-422 Signal Levels. Figure 3-16. Rear View of the Interface Converters Serial Connector. Page Page 3.9 General CAUTION Page RS-232IEEE 488 INTERFACE CONVERTER 4.1 Controller-Mode (Serial to IEEE) Operation 4. Controller Operation 4.2 Serial and IEEE Terminator Substitution 4.3 IEEE Address Selection Figure 4-1. Switch SW3: Selecting the IEEE Address. 4.4 Talk-Back Features Figure 4-2. Switch SW1: Enabling or Disabling Talk-Back on Terminator. Figure 4-3. Switch SW2: Enabling or Disabling Talk-Back on Timeout. Page 4.5 Plotter Applications Figure 4-4. A PC-Based Graphics System. Figure 4-5. Selecting RS-232 Signal Levels. Figure 4-6. Interface Converter Settings for Use with HP 7580A Plotter on an IBM PC. SW2 SW3 SW1 Figure 4-7. MacPlot Configuration Screen. Figure 4-8. A Macintosh Based Graphics System. Interface Converter IEEE 488 RS-422 Page Figure 4-10. Interface Converter Settings for Use with HP 7580A Plotter on a Macintosh. Page 5. Peripheral Operation 5.1 Peripheral-Mode Operation 5.2 Serial and IEEE Input Buffers 5.3 IEEE Data Transfers Page RS-232IEEE 488 INTERFACE CONVERTER Figure 5-1. Switch SW1: Enabling or Disabling SRQ on Last Terminator. Figure 5-2. Serial Poll Status Byte. 5.4 Serial-Poll Status-Byte Register Page 5.5 Use of Serial and Bus Terminators 5.6 IEEE 488 Bus Implementation Page 5.7 IEEE Address Selection Figure 5-3. SW3 View for IEEE Address Selection. 6. IEEE 488 Primer 6.1 History 6.2 General Structure Page Figure 6-1. IEEE 488 Bus Structure. 6.3 Send It to My Address 6.4 Bus Management Lines 6.5 Handshake Lines Figure 6-2. IEEE Bus Handshaking. 6.6 Data Lines 6.7 Multiline Commands Page 6.8 More on Service Requests Page 7.1 Theory of Operation 7. Theory of Operation and Board Layout 7.2 Board Layout CHAPTER 7: Theory of Operation and Board Layout Figure 7-1. Component Layout of the Interface Converters Motherboard. Figure 7-2. Component Layout of the Interface Converters Serial I/O board. APPENDIX A: Sample Dumb-Terminal Program Appendix A. Sample Dumb-Terminal Program Appendix B. Character Codes and IEEE Multiline Messages Page Index INDEX