HP E1429A manual OUTPEXT1STAT Ontrigsour EXT1OUTPEXT1STAT OFF

Models: E1429A

1 420
Download 420 pages 44.04 Kb
Page 29
Image 29

How to Execute Coupled Commands

Terminating

Commands

Suppressing the

End-Of-Line

Terminator

Coupled commands can cause “Settings conflict” errors when the program executes. When a coupled command is executed, the command setting is evaluated by the digitizer processor. If the setting causes an illegal digitizer configuration, a "Settings conflict" error occurs. The error message lists the conflicting settings, and then reports the values set by the digitizer processor.

The "Comments" section of each command reference entry (Chapter 4) indicates if a command is coupled, and if it is, what the coupling constraints are.

To prevent possible "Settings conflict" errors, coupled commands must be contiguous and executed in the same program statement. This is done by placing the commands in the same program line, or for HP BASIC programs, by suppressing the EOL terminator until the last (coupled) command has been sent.

To send multiple commands in a single line or in a single statement, the commands are linked with a semicolon (;) and a colon (:). This is illustrated in the following lines:

OUTP:EXT1:STAT ON;:TRIG:SOUR EXT1;:OUTP:EXT1:STAT OFF

or

OUTP:EXT1:STAT ON; :TRIG:SOUR EXT1; :OUTP:EXT1:STAT OFF

Notice that the semicolon (;) and colon (:) link commands within different subsystems. Only a semicolon (;) is required to link commands at the same level within the same subsystem.

Sending the commands as shown prevents "Settings conflict" errors. The command settings are not evaluated until the EOL terminator is received after the last command. If these commands were sent individually (an EOL terminator after each command), a "Settings conflict" error would occur because of the coupling between OUTP:EXT1:STAT ON and TRIG:SOUR EXT1.

A SCPI command string is terminated with a line feed (LF) and/or with an End Or Identify (EOI) message. The carriage return (CR) is ignored.

Suppressing the end-of-line (EOL) terminator on a command line allows coupled commands to be sent on separate lines, yet as a single program statement. In HP BASIC programs, the EOL terminator is suppressed by

Chapter 1

Getting Started 29

Page 29
Image 29
HP E1429A manual OUTPEXT1STAT Ontrigsour EXT1OUTPEXT1STAT OFF