Programming instructions

Programming the Status Register System
Status Groups
Chapter 3 115
Status Groups
The Standard Operation Status Group and the Data Questionable Status Group consist of the
registers listed below. The Standard Event Status Group is similar but does not have negative
or positive transition filters or a condition register.
Condition
Register A condition register continuously monitors the hardware and firmware
status of the signal generator. There is no latching or buffering for a
condition register; it is updated in real time.
Negative
Transition
Filter A negative transition filter specifies the bits in the condition register that
will set corresponding bits in the event register when the condition bit
changes from 1 to 0.
Positive
Transition
Filter A positive transition filter specifies the bits in the condition register that
will set corresponding bits in the event register when the condition bit
changes from 0 to 1.
Event
Register An event register latches transition events from the condition register as
specified by the positive and negative transition filters. Once the bits in the
event register are set, they remain set until cleared by either querying the
register contents or sending the *CLS command.
Event
Enable
Register An enable register specifies the bits in the event register that generate the
summary bit. The signal generator logically ANDs corresponding bits in the
event and enable registers and ORs all the resulting bits to produce a
summary bit. Summary bits are, in turn, used by the Status Byte Register.
A status group is a set of related registers whose contents are programmed to produce status
summary bits. In each status group, corresponding bits in the condition register are filtered
by the negative and positive transition filters and stored in the event register. The contents of
the event register are logically ANDed with the contents of the enable register and the result
is logically ORed to produce a status summary bit in the Status Byte Register.