On power-up, the instrument is always in the manual operating state and can be operated via the front panel controls. The instrument is switched to remote control in the following cases:
| With active GPIB bus | as soon as the Remote Enable (REN) GPIB line is asserted by the controller. |
| With active RS-232 interface | as soon as the instrument receives any characters via the interface. |
Operation via the front panel is disabled. The instrument remains in the remote state until it is reset to the manual state via the front panel or via GPIB bus (see section Return to Manual Operation).
Note: Local to remote
transition and signalling states
Switching from manual operation to remote control does usually not affect
the device settings. However, if the CMU operates in a Non Signalling
test mode, all generators are switched off. In a Signalling mode,
the current connection or call is dropped and the CMU returns to its default
signalling state.
To change this behavior and preserve the generator and signalling states
in a local to remote transition, the command SYSTem:GTRMode:COMPatible
OFF can be used.
Note: Accelerating the Shut
Down Process
The version of the Front Module controller has an impact on the shut down
process of the instrument; see Switching
off the Instrument in chapter 1 of your printed manual. When operating
instruments equipped with an FMR 6 in remote control mode, it is recommended
to disable the nonvolatile RAM, see command SYSTem:NONVolatile:DISable.
Indications during Remote Control
Setting the Transmission Parameters (RS-232 interface)