This attribute records the reason the bus test ended. It contains one
of the following values.
neverStarted: the bus test has not been started
testRunning: the bus test is currently running
testTimeExpired: the bus test ran for the specified duration
stoppedByOperator: a STOP command was issued
selfTestFailure: a failure was detected during the bus tap self-test
clockSourceFailure: a failure was detected during the test of the
active control processor (CP) clock source
broadcastFailure: a failure was detected during the broadcast test