topic Re: VISA write problem in LabVIEW

VISA write problem

opium — Tue, 12 Jul 2011 19:04:02 GMT

hi, people. I'm having some problems with the VISA write module by USB-HID.
I'm been able of receive data from the pic by hid-interrupt, using VISA's particular event, but i cannot send data out (pc-pic); it just get stuck when i asked for it.
i don't know if it is a sync problem between the device and the pc -issue that i have had with USB BULK-, or just bad programming.

particularly i'm using a modified version of the HID MOUSE EXAMPLE SIMPLE, and a pic18f4550.
the structure of the pic firmware is something like this:

if some external event then send data.
then, see if there are some data out pending.
if not, repeat loop.
everything using the same endpoint nº1.

thanks a lot for the help.

Re: VISA write problem

FloresFe — Mon, 15 Aug 2011 14:36:31 GMT

Hello! It might be going wrong because you're not using a USB functionm to do that. You should to use the "VISA USB Control Out Control" instead "VISA Write" Take a look at the "USB RAW - Control.vi" example. It's too close to what you want. Go to Help>>Find Examples. In the Browse tab, go to Hardware Input and Output>>VISA>> USB RAW - Control.vi

Re: VISA write problem

opium — Mon, 15 Aug 2011 22:34:19 GMT

thanks a lot, ill give it a try,

Re: VISA write problem

FloresFe — Tue, 16 Aug 2011 13:10:12 GMT

Please, let me know if that work!

Regards