Modbus communication through USB

[yann_john]

Hello everyone,

I am working on a project where I need to acquire datas stored in a captor via modbus/rtu (rs 485).

So far I've been able to get them via the rs 232 port of my 9076 cRIO using a rs 485 to rs 232 converter. The thing is I'd like to use the usb port instead of the rs 232 (because we need the rs 232 for another purpose).

Does anyone know how I could do that ? The idea would be to able to choose the USB port via VISA knowing that nothing appears in MAX when I connect the captor to the USB port using a rs 485 to usb converter.

Thanks a lot. Yann.

[Danubio]

Hi,

Please review the following source for getting started:

Can I Control a USB Device with NI-VISA on a Real-Time Controller?
http://digital.ni.com/public.nsf/allkb/5F30CD20D4D986CC862576CF00748B15

Regards,

Daniel C.