Stanford Research Systems SR124 Operation And Service Manual page 79

4.5 Status model
4.5.3.1 Standard event status enable (ESE)
SR124 Analog Lock-In Amplifier
EXE : Execution Error. Indicates the error in a command that was
successfully parsed. Out-of-range parameters are an example.
CME : Command Error. Indicates a command parser-detected error.
The ESE acts as a bitwise AND with the ESR register to produce the
single-bit ESB message in the Status Byte Register (SB). The register
can be set and queried with the *ESE(?) command.
At power-on, this register is cleared.
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