Appendix E
Status model
In this appendix:
Overview .................................................................................. E-1
Clearing registers and queues ................................................ E-12
Programming and reading registers ....................................... E-13
Status byte and service request (SRQ) .................................. E-14
Status register sets ................................................................. E-18
Queues ................................................................................... E-25
TSP-Link system status .......................................................... E-26
Overview
Each Keithley Instruments Model 2651A High Power System SourceMeter
®
Instrument provides a
number of status registers and queues that are collectively referred to as the "status model." Through
manipulation and monitoring of these registers and queues, you can view and control various
instrument events. Commands included in your test program can determine if a service request
(SRQ) event has occurred and the cause of the event. The heart of the status model is the Status
Byte Register. All status model registers and queues eventually flow into the Status Byte Register. As
a programmer, you are in full control of all enable registers, while the High Power System
SourceMeter
®
Instrument has full control of all event status registers. In order for an event to be
accounted for in the register's summary bit, first enable it by setting the appropriate bit in the
applicable enable register. The entire status model is illustrated in the
Status Byte Register
The Status Byte Register receives summary bits from the other status register sets and queues, and
also from itself (which sets the Master Summary Status, or MSS, bit). For details see
