AnsweredAssumed Answered

HP 436A driver

Question asked by larsulrich on Apr 24, 2012
Hello, I am trying to make a labview driver to use my HP 436A and am running into problems with the auto-ranging of the HP and reading values from the device.

Auto-ranging:  All of the programming commands for the HP are pretty basic, the auto range command is simply "9."  However, sending this command does not set the HP to an appropriate range, and I often get underrange/overrange indicators.  All of the manually selected ranges seem to work, but for the final application of this program I will need the auto-range capabilities.  Is there a trick to getting this to work?  Because it seems that I cannot simply send the device a string "9D+T" (autorange, dBm, cal off, trigger w/ settling) and have it set the range correctly.  The D and + commands seem to work, and I assume the T command will (though I can't get past the ranging so who knows).

Reading Values:  Usually labVIEW's VISA read function works, though every now and again I get a timeout error message associated with the read function, and once this happens, I need to power cycle the HP 436, otherwise I won't be able to read from it.

I added the driver I have made for labVIEW 8.5 in case you want to take a look.

Thanks for the help