9 - Remote Operation
35
QPX750 Instruction Manual
9.4.4
Status Byte Register and Service Request Enable Register
These two registers are implemented as required by the IEEE Std. 488.2.
Any bits set in the Status Byte Register which correspond to bits set in the Service Request Enable
Register will cause the RQS/MSS bit to be set in the Status Byte Register, thus generating a Service
Request on the bus.
The Status Byte Register is read either by the *STB? command, which will return MSS in bit 6, or by a
Serial Poll which will return RQS in bit 6. The Service Request Enable register is set by the *SRE<NRF>
command and read by the *SRE? command.
Bit 7
STATus:OPERation summary bit. This bit is set if any bits in the STATus:OPERation
register correspond to bits set in the STATus:OPERation:ENABle register
Bit 6
RQS/MSS. This bit, as defined by IEEE Std. 488.2, contains both the Requesting
Service message and the Master Status Summary message. RQS is returned in
response to a Serial Poll and MSS is returned in response to the *STB? command.
Bit 5
ESB. The Event Status Bit. This bit is set if any bits set in the Standard Event Status
Register correspond to bits set in the Standard Event Status Enable Register.
Bit 4
MAV. The Message Available Bit. This will be set when the instrument has a
response message formatted and ready to send to the controller. The bit will be
cleared after the Response Message Terminator has been sent.
Bit 3
Not used.
Bit 2
Error Queue is not empty. This will be set when there is one or more entries in the
error queue.
Bit 1
Not used.
Bit 0
LIM1. This will be set if any bits in the Limit Event Status register for output1 are set
and corresponding bits are set in the Limit Event Status Enable register LSE1.
