CMU Measurement Control 
1100.4903.12 5.33  E-8 
Generator Control 
The commands used for control of the CMU's RF and AF signal generators are analogous to the meas-
urement control commands explained on page 5.28. The generators are in one of the following two 
generator states: 
OFF  generator switched off, resources released 
RUN generator running 
The RUN state corresponds to the status indication ON in the RF generator softkey (see section Ana-
lyzer/Generator Menu in Chapter 4). 
The relation between generator commands and generator states is shown in the following diagram:  
 
OFF RUN
INITiate
ABORt
INITiate
ABORt
 
Fig. 5-8  Generator states and control commands 
Generator control commands are recognized by the second-level keyword RFGenerator or AFGen-
erator. The generator control commands behave as follows: 
INITiate: 
RFGenerator 
 
INITiate: 
AFGenerator... 
Starts the generator, reserves all necessary hardware resources and 
changes to the generator state RUN.  
As illustrated in Fig. 5-8, INITiate can be called in any generator state. If 
the generator is already running (RUN), INITiate has no effect.  
If the generator can not be started due to a resources conflict it remains in 
the  OFF state, and the measurement status returned by the 
FETCh:<meas_obj>:STATus? is ERR. At the same time the SCPI error 
–213, Init ignored, is generated. 
 
Possible resources 
conflicts 
•  The RF connector is already allocated by another generator. The other 
generator must be switched off first. 
 
Sequential execution  INITiate is implemented as a sequential command. The *OPC command 
(see Chapter 6, Common Commands) can be applied together with the 
INITiate command. 
 
ABORt: 
RFGenerator 
 
ABORt: 
AFGenerator... 
Switches the generator off, releases the hardware resources for other gen-
erators, and changes to the generator state RUN.  
As illustrated in Fig. 5-8, ABORt can be called in any generator state. If the 
generator is switched off (OFF), ABORt has no effect.  
 
Sequential execution  ABORt  is implemented as a sequential command. The command is not 
terminated before the generator is completely switched off. 
 
Note:  In some measurements (e.g. in function group Audio), several RF or AF generators can be 
used, each of them corresponding to a separate application. In this case, one generator 
must be switched off (ABORt:...) before the application is changed and another gen-
erator is started. Otherwise, the measurement will be stopped and the CMU will display an 
error message.