Tektronix WCA230A, Programmer'S Manual, Page: 615 / 678

Status and Events
WCA230A & WCA280A Programmer Manual
3- 15
The IEEE-488.2 common commands include the following synchronizing
commands:
*OPC
*OPC?
*WAI
Using the *OPC Command.
The *OPC command sets the SESR OPC bit when all
the operations for which it is waiting are completed. If the GPIB interface is in
use, you can synchronize the execution by using this command together with the
serial polling or service request function.
The following is a command sequence example:
*ESE 1 // Enable the ESER OPC bit
*SRE 32 // Enable the SRER ESB bit
:ABORt;INITiate:IMMediate;*OPC
// Wait for SRQ to provide synchronization
Using the Query *OPC?
The query *OPC? writes ASCII code “1” into the Output
Queue when all operations for which it is waiting are completed. You can
provide synchronization using the command string as the following example:
:ABORt;INITiate:IMMediate;*OPC?
The command waits until “1” is written into the Output Queue. When the
command goes to the Output Queue to read the data, a time-out may occur
before the data is written into the queue.
Using the *WAI Command.
After the process of the preceding command is
completed, the *WAI command begins to execute the process of the next
command as the following example:.
:ABORt;INITiate:IMMediate;*WAI
// Wait for the *WAI process to provide
synchronization
Using Synchronizing
Commands