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STATus Subsystem
Status register programming lets you determine the operating condition of the
instrument at any time. The instrument has three groups of status registers; Op-
eration, Questionable, and Standard Event. The Operation and Questionable
status groups each consist of the Condition, Enable, and Event registers as well
as NTR and PTR filters.
Status Register
The Operation and Questionable status groups use four different types of regis-
ters to track qualify, flag, and enable instrument events. The Standard Event
group only uses Event and Enable registers.
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A Condition register continuously monitors the state of the instrument. The
bits in the condition register are updated in real time and the bits are not
latched.
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An PTR/NTR register qualifies the signal that passes to the event register.
When a PTR bit is set, signals with positive edge transition pass to the event
register. When an NTR bit is set, signals with a negative edge transition pass
to the event register. When both bits are set, all signal pass. When neither
bits are set, no signals pass.
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An Event register latches transitions that pass through the PTR and NTR
registers. When an event bit is set, it remains set until the Event register is
read. Reading the Event register clears it.
•
An Enable register defines which bits in the event register will be reported to
the Status Byte register. You can write to or read from an enable register.
Operation Status Group
These registers record signals that occur during normal operation. The groups
consist of a Condition, PTR/NTR, Event, and Enable register.
Questionable Status Group
These registers record signals that indicate abnormal operation. The groups
consist of a Condition, PTR/NTR, Event, and Enable register.
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