Keysight 8990B, Programming Manual

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1 8990B Remote Operation
40 Keysight 8990B Programming Guide
Particular bits in the Status Byte register are cleared when:
– The Standard Event, Questionable Status, Operation Status, and Device Status
are queried.
– The error/event queue becomes empty.
– The output queue becomes empty.
The Status Byte enable register (
*SRE <NRf> , service request enable) is cleared
when you:
– cycle the 8990B power.
– execute an
*SRE 0
command.
Using *STB? to read the Status Byte
*STB? (status byte query) is similar to a serial poll except that it is processed like
any other 8990B command. The
*STB?
query returns the same result as an
IEEE-488 serial poll except that the request service bit (bit 6) is not cleared if a
serial poll has occurred. The
*STB?
query is not handled automatically by the
IEEE-488 bus interface hardware, and the query is executed only after previous
commands have completed. Using the
*STB?
query does not clear the Status Byte
summary register.
Standard Event register
The Standard Event register reports the following types of instrument events:
power-on detected, command and syntax errors, command execution errors,
self-test errors, query errors, or when an overlapped command completes
following an *OPC command. Any or all of these conditions can be reported in the
Standard Event summary bit through the enable register. You must write a
decimal value using the *ESE <NRf> (event status enable) command to set the
enable register mask.