CMU  GPIB Bus Messages 
1100.4903.12 5.5  E-8 
Via GPIB bus:    ... 
CALL IBLOC(device%)  Set instrument to manual operation 
... 
 
Equivalent CMU-specific command, also for serial interface: *GTL 
 
Target Menu  On switching over from remote to manual control, the CMU preserves the cur-
rent measurement and generator states and the current signalling state (if a 
Signalling test mode is active). The instrument tries to open the menu that the 
user is likely to prefer, i.e. the measurement menu of the current, running 
measurement. If several measurements are running in parallel, the instrument 
applies the following selection rules to resolve the ambiguity and determine a 
preferred menu:  
–  The preferred menu must belong to a measurement that is in the RUN or 
HLT state (see section Measurement Control Commands and States on p. 
5.28 ff.). RDY  measurements and suppressed measurements are dis-
carded. 
–  Measurement menus of the main application have the priority over configu-
ration menus (e.g. for signalling and generators) and menus for additive 
applications (e.g. an Audio measurement that is performed in the context 
of a GSM-MS main application).   
–  Out of several running measurements of the same hierarchy level, the last 
one that was initiated (INITiate:… or READ:…?) is preferred.   
  If no measurement is in the RUN or HLT state, the last measurement that was 
aborted (ABORt:…) is preferred.  
 
 
 
Setting the Transmission Parameters (RS-232 interface) 
To ensure a correct data transmission, the parameters of the instrument and the controller must be set 
identically. The number of data and stop bits, the parity, baud rate and the handshake mode can be set 
independently for the two interfaces COM 1 and COM 2 in the Setup - Comm. menu: 
 
! Open Setup - Comm. menu, 
! Press one of the softkeys to select interface COM 1 or COM 2, 
! Use the cursor keys and the rotary knob to select and change desired parameters, 
! Terminate input using the [ENTER] key. 
 
 
 
GPIB Bus Messages 
The messages transferred via the data lines of the GPIB bus (see Chapter 8) can be divided into two 
groups: 
-   interface messages 
-  device messages