User`s manual

50 Chapter 1
O:\Manuals\E6380A_Progguid\Book\Usehpib.fm
Using HP-IB
Remote/Local Modes
Local Lockout
The Local Lockout mode disables the front-panel LOCAL key and
allows return to Local mode only by commands from the System
Controller (Clear Lockout/Set Local message).
When a data transmission to the Test Set is interrupted, which can
happen if the LOCAL key is pressed, the data being transmitted may be
lost. This can leave the Test Set in an unknown state. The Local
Lockout mode prevents loss of data or system control due to someone
unintentionally pressing front-panel keys.
NOTE Return to Local mode can also be accomplished by setting the POWER
switch to OFF and back to ON. However, returning to Local mode in
this way has the following disadvantages:
1. It defeats the purpose of the Local Lockout mode in that the Active
Controller will lose control of the test set.
2. Instrument configuration is reset to the power up condition thereby
losing the instrument configuration set by the Active Controller.
Clear Lockout/Set Local
The Test Set returns to Local mode when it receives the Clear
Lockout/Set Local message. No instrument settings are changed by the
transition from Remote mode with Local Lockout to Local mode but
triggering is reset to FULL SETTling and REPetitive RETRiggering.