Modbus RTU communication problem on specific device.

ufkyldrm · Joined: 21 May 2018 Posts: 27

Hi guys.

This device has modbus rtu protocol but I can't read its register values.

its communication datasheet.
https://www.dosyaupload.com/dZt4

I tried it with modbus poll or Kepware Opc server... As I said with these softwares i got what I want, up to now. These softwares have a search function for devices which has modbus rtu. My opinion, it is not parameter issue.

I there any way to get value from this device, maybe with pic?

Any advice? Smile

Ttelmah · Joined: 11 Mar 2010 Posts: 19549

Triple check your communication parameters. Probably something like incorrect parity.
Unless you are actually using a PIC with CCS, this is off topic here.

Jerson · Joined: 31 Jul 2009 Posts: 125 Location: Bombay, India

First confirm using a software as suggested in the linked manual. If you are convinced there is no problem with the hardware, only then should you try with a PIC.

Probably wrong communication parameters (software shows correct should be 9600-N-8-1) may be the cause for no communication.

Since it is RS485, check the connections of your D+ D- lines as well.