Tektronix Keithley 2651A Reference Manual page 906

Model 2651A High Power System SourceMeter® Instrument Reference Manual
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Bit B6, Request Service (RQS)/Master Summary Status (MSS): Set bit indicates that an
enabled summary bit of the Status Byte Register is set. Depending on how it is used, bit B6 of the
Status Byte Register is either the Request for Service (RQS) bit or the Master Summary Status
(MSS) bit:
▪
When using the GPIB or VXI-11 serial poll sequence of the Model 2651A to obtain the status
byte (serial poll byte), B6 is the RQS bit. See
details on using the serial poll sequence.
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When using the *STB? common command or status.condition
request commands
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Bit B7, Operation Summary (OSB): Set summary bit indicates that an enabled operation event
has occurred.
Service Request Enable Register
The Service Request Enable Register controls the generation of a service request. This register is
programmed by the user and is used to enable or disable the setting of bit B6 (RQS/MSS) by the
Status Summary Message bits (B0, B1, B2, B3, B4, B5, and B7) of the Status Byte Register. As
shown in Status Byte Register
summary bits (&) with the corresponding enable bits of the Service Request Enable Register. When a
logical AND operation is performed with a set summary bit (1) and with an enabled bit (1) of the
enable register, the logic "1" output is applied to the input of the logical OR gate and, therefore, sets
the MSS/RQS bit in the Status Byte Register.
You can set or clear the individual bits of the Service Request Enable Register by using the *SRE
common command or status.request_enable. To read the Service Request Enable Register,
use the *SRE? query or print(status.request_enable). The Service Request Enable Register
clears when power is cycled or a parameter value of 0 is sent with a status request enable command
(for example, a *SRE 0 or status.request_enable = 0 is sent). The commands to program and
read the SRQ Enable Register are listed in
15-19).
2651A-901-01 Rev. C October 2021
(on page 15-19) to read the status byte, B6 is the MSS bit.
(on page 15-15), a logical AND operation is performed on the
Status byte and service request commands
Serial polling and SRQ (on page 15-18) for
Status byte and service
Section 15: Status model
(on page
15-17