B&K Precision 4079 - Manual - Manual (Page 93)

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4.17 GPIB Communication Protocol
4.17.1 General
This appendix describes the effects of interface messages on waveform generator operation and uses abbreviations from the
IEEE Standard 488.1-1987.
4.17.2 Responses to IEEE-488.1 Interface Messages
Interface messages and the effects of those messages on the instrument interface functions are defined in IEEE Standard
488.1-1987. Where appropriate, the GPIB code is listed, in decimal.
UNL-Unlisten (63 with ATN)
UNT-Untalk (95 with ATN)
The UNL command places the listener function to its idle (unaddressed) state. In this idle state, the waveform generator
cannot accept commands from the GPIB.
The UNT command places the talker function to its idle state. In this idle state, the waveform generator cannot output data
through the GPIB.
When the talker and listener functions are idle, the front-panel ADRS indicator is off. If the waveform generator is talk-
addressed or listen-addressed, the ADRS indicator lights.
IFC-Interface Clear (Bus pin 9)
The IFC message places both the listener and talk functions to idle states. When the talker and listener functions are idle, the
front-panel ADRS indicator is off.
The IFC pulse is >= 100us.
DCL-Device Clear (20 with ATN)
The Device Clear message resets GPIB communication. That is, the DCL message clears all input and output messages, as
well as all unexecuted settings.
SDC-Selected Device Clear (4 with ATN)
The SDC message causes the same response as the DCL message. However, the waveform generator only responds if it is
listen-addressed.
GET-Group Execute Trigger (8 with ATN)
The waveform generator responds to the Group Execute Trigger message only if it is listening addressed and the device
trigger function is enabled. The TRIGger:MODE must be in TRIG, CONTinuous, or BURst and the TRIGger:SOURce must
be set to BUS to enable device triggering via GET.
SPE-Serial Poll Enable (24 with ATN)