54
S:\agilent\8920\8920b\PRGGUIDE\BOOK\CHAPTERS\usehpib.fb
Chapter 1, Using GPIB
Remote/Local Modes
Local To Remote Transitions
The Test Set switches from Local to Remote mode upon receipt of the Remote
message (REN bus line true and Test Set is addressed to listen). No instrument
settings are changed by the transition from Local to Remote mode, but triggering
is set to the state it was last set to in Remote mode (i f n o previous setting, the
default is FULL SETTling and REPetitive RETRiggering). The R annunciator in
the upper-right corner of the display is turne d on.
When the Test Set makes a transition from local to remote mode, all currently
active measurements are flagged as invalid causing any currently available
measurement results to become unavailable. If the GPIB trigger mode is
:RETR REP then a new measurement cycle is started and measurement results
will be available for all active measurements when valid results have been
obtained. If the GPIB trigger mode is :RETR SING then a measurement cycle
must be started by issuing a trigger event. Refer to “Triggering Measurements” on
page 224 for more information.
Remote To Local Transitions
The Test Set switches from Remote to Local mode upon receipt of the Local
message (Go To Local bus message is sent and Test Set is addressed to listen) or
receipt of the Clear Lockout/Set Local message (REN bus line false). No
instrument settings are changed by the transition from Remote to Local mode, but
triggering is reset to FULL SETTling and REPetitive RETRiggering. The R
annunciator in the upper right corner of the display is turned off.
If it is not in Local Lockout mode the Test Set switches from Remote to Local
mode whenever the front-panel LOCAL key is pressed.
If the Test Set was in Local Lockout mode when the Local message was received,
front-panel control is returned, but Local Lockout mode is not clea red. Unless the
Test Set receives the Clear Lockout/Set Local message, the Test Set will still be in
Local Lockout mode the next time it goes to the Remote mode.