Hioki ST4200 Instruction Manual page 176

Set the OPC bit of the Standard Event Status Register (SESR) to 1 when
finished all pending operations
*OPC
Syntax
Command
*OPC
Query
*OPC?
Response
A<NR1>
Details
*Sets the Standard Event Status Register (SESR) OPC bit (bit 0) to 1 when all commands prior to the OPC
command have finished processing.
*Responds with 1 when all commands prior to *OPC? have finished.
Example
*OPC
*OPC?
(Response)1(When HEADER OFF)
HIOKI ST4200B971-00
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