I cannot find this VISA driver you speak of (maybe it is no longer in the NI library) but am also interested in runining the SR830 off of a serial port. I thought it might save some time if I could find the one you reference or yours. Can you point me in the right direction? Would you be willing to share yours?
The only amplifier with a serial port driver on the lab view search page is the 560 which is a pre-amplifier, but I will look at this as well. The SR844 has a gpib driver. Or am I not looking in the correct place?