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Programming
Reviewing SCPI Syntax Rules
Combine commands from different subsystems
You can send commands and program queries from different sub-
systems on the same line. Simply precede the new subsystem by a
semicolon followed by a colon. In the following example, the colon and
semicolon pair before DISP allows you to send a command from
another subsystem.
OUTPUT 720;”:CALC2:PEXC 12;:DISP:WIND:GRAP:STAT OFF”
Sending common commands
If a subsystem has been selected and a common command is received
by the instrument, the instrument remains in the selected subsystem.
For example, if the program message
”DISPLAY:MARK:MAX:LEFT;*CLS;DISP:MARK:MAX:RIGH”
is received by the instrument, the Display subsystem remains selected.
If some other type of command is received within a program message,
you must reenter the original subsystem after the command.
Adding parameters to a command
Many commands have parameters that specify an option. Use a space
character to separate the parameter from the command as shown in
the following line:
OUTPUT 720;”:INIT:CONT ON”
Separate multiple parameters with a comma (,). Spaces can be added
around the commas to improve readability.
OUTPUT 720;”:MEAS:SCAL:POW:FREQ? 1300, MAX”
White space
White space is defined to be one or more characters from the ASCII
set of 0 through 32 decimal, excluding 10 (NL). White space is usually
optional, and can be used to increase the readability of a program.
Numbers
All numbers are expected to be strings of ASCII characters. Thus,
when sending the number 9, you would send a byte representing the
ASCII code for the character “9” (which is 57). A three-digit number
like 102 would take up three bytes (ASCII codes 49, 48, and 50). This