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Structure of a Command Line

A command line may consist of one or several commands. It is terminated by a <New Line>, a <New Line> with EOI or an EOI together with the last data byte. Visual BASIC automatically produces an EOI together with the last data byte.

Several commands in a command line must be separated by a semicolon ";". If the next command belongs to a different command system, the semicolon is followed by a colon.

Example: CALL IBWRT(device%, "TRIGger:SOURce EXTern;:FETch:POWer:STATus?")
  This command line contains two commands. The first command belongs to the TRIGger system and defines the trigger source (external trigger). The second command belongs to the FETCh system and returns the status of the power measurement.

If the successive commands belong to the same system, having one or several levels in common, the command line can be abbreviated. To this end, the second command after the semicolon starts with the level that lies below the common levels. The colon following the semicolon must be omitted in this case.

   

 

Example: CALL IBWRT(device%, "TRIG:SOUR EXT;:TRIG:THR LOW")
  This command line is represented in its full length and contains two commands separated from each other by the semicolon. Both commands are part of the TRIGger command system, i.e. they have one level in common.

When abbreviating the command line, the second command begins with the level below TRIG. The colon after the semicolon is omitted.

The abbreviated form of the command line reads as follows:

CALL IBWRT(device%, "TRIG:SOUR EXT;THR LOW")

However, a new command line always begins with the complete path.

Example:
CALL IBWRT(device%, "TRIG:SOUR EXT ")

CALL IBWRT(device%, "TRIG:THR LOW ")

 


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