R&S NRP  Remote Control - Fundamentals 
1144.1400.12 5.9  E-3 
Structure of a Program Message 
A program message may contain one or several commands. Several commands in a program message 
are separated by a semicolon (;). If the next command belongs to a different command system, the 
semicolon is followed by a colon. The colon stands for the root node of the command tree. 
 
Example: 
SYSTem:TIME 20,30,00;:SENSe:FUNCtion "POWer:AVG" 
 
This program message contains two commands. The first command belongs to the 
SYSTem system and is used to set the time of the system clock. The second command 
belongs to the SENSe system and must be preceded by a colon. Otherwise confusion 
might be caused if the SYSTem tree also had a subordinate SENSe node. In this case, it 
would be possible to omit the introductory keyword SYSTem. (see the following 
explanation:) 
 
If the successive commands belong to the same system and therefore have one or several common 
levels, the program message may be abbreviated. The second command following the semicolon then 
starts at the level that is below the common levels. The colon after the semicolon must be omitted in 
this case. 
 
Example: 
SENSe2:TIMing:STARt 10; SENSe2:TIMing:STOP 10 
 
This program message contains two commands separated by a semicolon. Both 
commands belong to the SENSe system and its TIMing subsystem, i.e. they have two  
common levels. 
In the abbreviated program message the second command starts at the level below 
SENSe:TIMing. The colon after the semicolon has to be omitted. 
The short form of the program message is: 
 
SENSe2:TIMing:STARt 10; STOP 10 
 
A new program message always starts with the full path however. 
 
Example: 
SENSe2:TIMing:STARt 10 
SENSe2:TIMing:STOP 10 
 
 
Note:  Processing of a program message is aborted if an error occurs. If only 
sensor 2 is connected to a multichannel device, for example, the program 
message 
 
SENS1:FREQ 50 GHZ;:SENS2:FREQ 50 GHZ 
 
will be aborted after the first command and a second frequency setting will not be 
performed.