HP 53150A Series Programming Manual page 76

Chapter 3 Programming Your Counter for Remote Operation
Status Reporting
To read the event registers use:
:STATus:OPERation[:EVENt]?
:STATus:QUEStionable[:EVENt]?
Use event register queries or *CLS to clear event registers.
Event Enable Register
An event enable register selects which event bits in the corresponding
event register can generate a summary bit.
To write the event enable registers use:
:STATus:OPERation:ENABle
:STATus:QUEStionable:ENABle
To read the event enable registers use:
:STATus:OPERation:ENABle?
:STATus:QUEStionable:ENABle?
The event enable registers are cleared by :STATus:PRESet and
power-on.
3-36 Programming Guide