User`s manual

SCPI Command Execution
The following information should be remembered when executing SCPI commands.
Command
Coupling
Many of the AFG SCPI commands are value coupled. This means that sending a
command can change parameter values set by previous commands. Often, this
results in “ Settings Conflict” errors when the program executes. To prevent these
errors, the AFG commands must be executed in “ Coupling Groups” . The coupling
groups and associated commands are listed in Table B-2 in Appendix B.
The coupling groups identified in Table B-2 are frequency and voltage. Some
commands (like
[SOURce:]FUNCtion[:SHAPe]) are associated with both groups.
These commands are a bridge linking (coupling) the two groups. Commands not in
a coupling group must precede or follow commands in the coupling groups.
Executing un-coupled commands in a coupling group breaks the coupling and can
cause a “ Settings Conflict” error. Command queries (commands with
?) are
uncoupled commands and should be executed before or after coupled commands.
See “Executing Coupled Commands” on page 28 for information on executing
coupled commands.
MIN and MAX
Parameters in
Coupling Groups
When MINimum or MAXimum is the parameter of a command in a coupling group,
that command should be the last command executed in the group. Unlike other
parameters that are set when an end-of-line indication is received,
MIN and MAX are
evaluated by the AFG processor when the command is parsed. Thus, the value of
MIN or MAX is based on the values of the other (coupling group) commands at that
time. “Settings conflict” errors will occur if the current values are incompatible
with an intended
MIN or MAX value. As a result, MIN and MAX are not
recommended for specifying the value of a parameter.
Linking
Commands
Linking IEEE 488.2 Common Commands.
Use a semicolon between the commands. For example:
*RST;*CLS;*OPC?
Linking Multiple SCPI Commands.
Use both a semicolon and a colon between the commands. For example:
SOUR:ROSC:SOUR INT1;:TRIG:STAR:SOUR INT1
Command
Choices
Some commands are listed as two commands separated with a vertical bar (“|” ).
This means that either command name can be used. For example, use either
:CW or
:FIXed when :CW|:FIXed is shown.
288 Command Reference Chapter 8