Anritsu MT8820A - Establishing Synchronization

7.7 Establishing Synchronization
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7.7 Establishing Synchronization
This section explains how to establish synchronization between commands transmit-
ted from the computer with the operation of the MT8820A.
7.7.1 Difference of synchronization depending on measurement start
command
When measurement is started using the SNGLS command, command processing is
assumed to have been completed even when the actual measurement has not yet.
That is, next command is executed even if measurement is being executed. The
SNGLS command is effective when a measured value during measurement is read,
and effective in measurement where measurement is endless, such as bit error rate
measurement.
In most measurements, it is necessary to read the measurement results after the
measurement has been completed. In this case, use SWP as a measurement start
command. Starting measurement using the SWP command puts the next command
in wait status until current measurement has been completed. Thus it is not neces-
sary to provide special processing for waiting for current measurement to be com-
pleted.
7.7.2 Establishing synchronization with the *OPC? command
Sending the *OPC? query to MT8820A provides synchronization, as below.
When the response to *OPC? is 1, it indicates that the immediately preceding com-
mand was completed. On the other hand, when the response is 0, it indicates that
the command has not yet been completed. Thus, synchronization is established by
waiting for the response to *OPC? to become 1.
7.7.3 Establishing synchronization corresponding to the status register
status
Sending the *ESR?, *ESR2? or *ESR3? to MT8820A provides synchronization.
Thus, synchronization is established by waiting for the response to be the expected
value. Event status register must be reset just before occurring the expected register.
In addition, the *OPC command must be sent before sending the target command
when using the *ESR? query.