Using The *Opc? Command; Using The *Opc Command To Assert Srq - Keysight 53147A Operating And Programming Manual

Using the *OPC? Command

This method is useful if you want to hold off execution of the program while you
wait for the instrument to complete any pending activity. In the *WAI example
above, the line following the *WAI command is accepted by the instrument.
However, the instrument does not execute the command because of the
preceding *WAI command. If this line had been a command to address another
instrument, it would be immediately executed. If you had wanted to hold off the
command to another instrument, you would use the *OPC? command instead of
the *WAI command.
Read the instrument. The program waits until the instrument returns a "1". (The GPIB
timeout must be set so that it is longer than the expected measurement time.)

Using the *OPC Command to Assert SRQ

This method is recommended when the instrument is interfaced with many other
instruments, any of which can assert SRQ. The commands *OPC, *ESE 1, and
*SRE 32 are used to assert the SRQ line to alert the computer that the instrument
has completed a measurement. It is up to the computer to use the serial poll
command to determine which of the instruments on the bus requested service.
Keysight 53147A/148A/149A Operating and Programming Guide
:AVERAGE:COUNT 50
:AVERAGE:STATE ON
:INIT
*OPC?
On INIT, take 50 measurements.
Enable averaging.
Start making measurements.
Tells the instrument to put a 1 in the output
buffer when 50th measurement is complete.
Programming 3
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