Keithley 2701, Service Manual

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B-24 Calibration Reference Model 2701 Service Manual
Error queue
As with other Model 2701 errors, any calibration error will be reported in the remote error
queue. You can read this queue by using the :SYST:ERR? query. The Model 2701 will respond
with the appropriate error message, as summarized in
Table B-5 .
Status byte EAV (Error Available) bit
Whenever an error is available in the error queue, the EAV (Error Available) bit (bit 2) of the
status byte will be set. Use the *STB? query to obtain the status byte, then test bit 2 to see if it
is set. If the EAV bit is set, an error has occurred and you can use the :SYST:ERR? query to
read the error and at the same time clear the EAV bit in the status byte.
Detecting calibration step completion
When sending remote calibration commands, you must wait until the instrument completes
the current operation before sending a command. You can use the *OPC? (operation complete)
query to help determine when each calibration step is completed.
With the *OPC? query, the instrument will place an ASCII 1 in the output queue when it has
completed each step. To use this method, allow a sufficiently long timeout period after sending
each calibration command, then test for an ASCII 1 in the output queue by sending *OPC?.