We normally operate the unit remotely. We're looking into a request to be able to have the operator halt the program, press Local, use the multi-meter for manual measurements, then restart the program and have the unit return to its previous programmed state. One suggestion was:
Set up a call back function invoked when the Local button is pressed When the callback function is invoked, set a global variable “Local” to true, save the present state of the DMM Using the SSTATE command, and send the GPIB GoToLocal command to allow the operator manual control. Before issuing any other IO to the DMM, check the “Local” global variable. If true, restore the saved state of the DMM with the RSTATE command ,send the GPIB LocalLockout command, set the “Local” variable false and continue with the intercepted IO.
Does this seem doable? How would we set up a callback for the Local key? I looked around for examples of setting interrupt handlers from specific keys but didn't have much luck.
Brian
Set up a call back function invoked when the Local button is pressed When the callback function is invoked, set a global variable “Local” to true, save the present state of the DMM Using the SSTATE command, and send the GPIB GoToLocal command to allow the operator manual control. Before issuing any other IO to the DMM, check the “Local” global variable. If true, restore the saved state of the DMM with the RSTATE command ,send the GPIB LocalLockout command, set the “Local” variable false and continue with the intercepted IO.
Does this seem doable? How would we set up a callback for the Local key? I looked around for examples of setting interrupt handlers from specific keys but didn't have much luck.
Brian
OUTPUT 722; “DEFKEY 1, ‘RQS 4; SRQ’”
This will assign the command string ‘RQS 4; SRQ’ to user defined key 1 (the numeric key 1). If the user hits the ‘1’ key when the keyboard is idle (no other menu entry in progress), this will pull up the defined command string, and then the user hits Enter to execute it. The ‘RQS 4’ command is necessary to enable the SRQ command to actually generate the SRQ.
This mechanism could be used to generate a second SRQ when the user is done with his front panel work, so the controller will have to keep track of how many events it has fielded.
Let me know if that works