5
Language Reference
78
Series N5700 User’s Guide
*SRE
*SRE?
This command sets the condition of the Service Request Enable
Register. This register determines which bits from the Status Byte
Register are allowed to set the Master Status Summary (MSS) bit and
the Request for Service (RQS) summary bit. A 1 in any Service
Request Enable Register bit position enables the corresponding
Status Byte Register bit and all such enabled bits then are logically
OR-ed to cause Bit 6 of the Status Byte Register to be set.
When the controller conducts a serial poll in response to SRQ, the
RQS bit is cleared, but the MSS bit is not. When *SRE is cleared (by
programming it with 0), the power supply cannot generate an SRQ to
the controller. The query returns the current state of *SRE.
*STB?
This query reads the Status Byte register, which contains the status
summary bits and the Output Queue MAV bit. Reading the Status
Byte register does not clear it. The input summary bits are cleared
when the appropriate event registers are read. The MAV bit is cleared
at power-on, by *CLS' or when there is no more response data
available.
A serial poll also returns the value of the Status Byte register, except
that bit 6 returns Request for Service (RQS) instead of Master Status
Summary (MSS). A serial poll clears RQS, but not MSS. When MSS is
set, it indicates that the power supply has one or more reasons for
requesting service.
Bit Position
7
6
5
4
3
2
1
−
0
Bit Value
128
64
32
16
8
4
−
Bit Name
OPER MSS
(RQS)
ESB
MAV QUES ERR
−
OPER = Operation status summary
MSS = Master status summary
(RQS) = Request for service
ESB = Event status byte summary
MAV = Message available
QUES = Questionable status summary
ERR = Error queue not empty
*WAI
This command instructs the power supply not to process any further
commands until all pending operations are completed. Pending
operations are as defined under the *OPC command. *WAI can be
aborted only by sending the power supply a Device Clear command.
