For the Operate Event register, you send STAT:OPER? For
the query.
Below are the definitions:
CAL (bit 0) – Calibration. This is only active when
unlocking in calibration mode. This is for factory use only.
On/Off (bit 1) – output state. When output turns ON, this
will flag to indicate output ON upon querying. So you
would get a decimal value 2 in the query return.
However, this is only for the ON state, not for OFF state.
WTG (bit 2) – Waiting for trigger. This is only used to
determine if instrument is in the state of waiting a trigger.
This would only be used for List mode as trigger is only
used to start a List program.