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General Programming Aspects
Status Model
Status Byte
The status byte summarizes the information from all other status groups.
The summary bit for the status byte actually appears in bit 6 (RQS) of the
status byte. When RQS is set it generates an SRQ interrupt to the
controller indicating that at least one instrument on the bus requires
attention. You can read the status byte using a serial poll or *STB?
Standard Event Status Group
Bit Description
0 Unused, always 0
1 Unused, always 0
2 Unused, always 0
3 QUESTionable Status Summ ary Bit
4 MAV—Message AVailable in output buffer
5 Standard Event Sta tus summary bit
6 RQS; ReQuest Service
7 OPERation Status summa ry Bit, unused
Bit Description
0 Operat ion Complete, set by *OPC
1Unused, always 0
2 Query Error
3 Device Dependent Error
4 Execution Error
5 Command Error
6Unused, always 0
7Power On