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Chapter 4, Status Reporting
Status Reporting
Condition Register /Transition Filters
A condition is a Test Set state that is either true or false.
Monitored Test Set states that are capable of remaining in each state for a time
period long enough to provide a realistic chance of being queried are assigned one
of the bits in the appropriate condition register. An example of this type of bit
would be FER Test Running, located in the Measuring status register group.
When an FER (Frame Error Rate) test is not running, this condition bit is false.
When an FER test is running, this bit will transition to a true state and remain
there for the duration of the FER test, which at a minimum will take several
seconds. During this time an external controller may periodically query the
Measuring status register and find that the bit is still true, indicating the test is still
running.
Monitored Test Set states that are transient, such as FER Test Passed in the
CDMA status register group, do not have a condition register bit assigned to them.
The reason for this is evident in the following description of the FER Test Passed
states. When an FER test passes, the condition bit toggles from false to true, then
is returned false so that it is in a state to signal the next occurrence of this
condition. The chances are very slight that an HP-IB query of the FER Test
Passed condition bit would ever return a true state indication.
In the following pages, each status register group description includes a table of
bit definitions. As part of each bit definition there is a column entitled “Is
Condition Register Implemented”, with a YES or NO identifier.
There is no latching or buffering of any bits in a Condition Register; it is updated
in real time. Condition Registers are read-only. Condition Registers in the Test Set
are 16 bits long and may contain unused bits. All unused bits return a zero value
when read.
For each bit that has a condition register implemented, the Transition Filters
determine which of two bit-state transitions will set the corresponding bit in the
Event Register.
See "Event Register" on page 111. Transition Filters may be set to
pass positive transitions (PTR), negative transitions (NTR) or either (PTR or
NTR). A positive transition means a condition bit changed from 0 to 1. A negative
transition means a condition bit changed from 1 to 0.
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