Sending Commands and Reading Back from the Unit Under Test

ProCal has the ability to perform fully closed-loop calibration and verification through the use of pre and post test commands on a test by test basis for maximum control over ranges etc.

To tell ProCal that the procedure will communicate with a UUT over a remote interface, the UUT traceable calibration category must be included on the second page of the procedure editor as below. This page is accessed when creating or editing a procedure and selecting uncertainty statements / manual traceable instruments.

To access the instrument control windows, open the procedure you wish to edit/create in ProEdit and select the test that requires commands and press the INSTRUMENTS tab

To send commands to a UUT, commands in the Instrument window must be prefaced with UUT with the command following

For example, with a SCIPI compatible instrument, the below command will set the 1V DC Range

UUT CONF:VOLT:DC 1

To perform a readback with automatic samples, a special header must be entered in the command window to inform ProCal that it should repeat lines below until the auto step requirements are met

>READBACK

To read back from an interface the FETCHREAD command must be entered between UUT and the command. For example, to perform readback from a SCIPI instrument

UUT FETCHREAD READ?

Will send the command READ? to the UUT and read the response from the UUT

The command MEAS=READ will inform ProCal to set the Result (i.e. the measurement) as the result of the READ from the UUT

If a delay is required between measurement loops the DELAY xx command can be used where xx is the delay in seconds, i.e. DELAY 1 will delay by 1 second.

To configure auto step the ADVANCED tab can have parameter for automatically moving to the next test entered : 

In this example, ProCal will dynamically determine when the UUT has become stable and then average 3 readings and then move on whether or not the test passes or fails. Note that Autostep is set to ON.

For more advanced programming, please contact Transmille for assistance