modbus rs485

[CJ_Butler__DASYLab_Pro]

Erfan,

Your message is more likely to be seen if you post it as a new topic.

[jeyadheepan]

Dear jack,

Ensure that to add the modbus library to your labview installation. Download it from the link below.

http://ftp.ni.com/pub/devzone/epd/nimodbus121.zip

Also ensure that you have created the CRC correctly. If you dont know about the CRC creation. Use the below link and download the vi and use it as a subvi in your program.

http://ftp.ni.com/pub/devzone/epd/crc-16.vi

Always follow the RTU-Modbus manual of the PID-500-x-x-04, which you can get  from the customer care of Selec.

With regards,

Jeyadheepan K. M

[smithd]

I'd personally suggest using the newer modbus library here, but I'm biased:

https://decibel.ni.com/content/docs/DOC-30140

You shouldn't really need to touch visa (or the crc) except potentially to set your 485 port to the appropriate wire mode (2-wire, 4-wire).

From the original post it sounds like visa is not installed, simple as that. Confirm you've downloaded and installed ni-serial from ni.com/downloads