5 Replies Latest reply on Jun 19, 2015 6:43 PM by CMata_Intel

    Edison RS-485 library



      Does anybody use intel edison communication over rs-485 modbus rtu?

      I have edison arduino board and rs-485 shield RS485 Shield.

      I connected arduino board with this shield to my meter and it works. But the same code on edison board doesn't work.

      I tried this sample RS-485 Module Tutorial for Arduino, Raspberry Pi and Intel Galileo but it also doesn't work.

        • 1. Re: Edison RS-485 library

          Hi NY;


          Are you having an error in the code or when you upload the code using the IDE?

          Are you testing the signal to check if there is activity in the lines?

          Which library are you using? this one?




          • 2. Re: Edison RS-485 library

            1. I have this error (arduino ide 1.6.4)


            I copied SPI forlder from IDE 1.5.3 to IDE 1.6.4 and got this massage


            2. I tested activity in the line using original arduino board and the same shield (another code and library)

            • 3. Re: Edison RS-485 library

              Hi NY


              I downloaded this libraries and I was able to replicate your issue.

              The error log says:

              fatal error: ../SPI/SPI.h: No such file or directory

              #include "../SPI/SPI.h"

              I did the following and I was able to compile/verify the code successfully

              Go to the folder RS485 and open the file named RS485.cpp


              Go to line#30 and change:

              #include "../SPI/SPI.h"


              #include <SPI.h>


              Let me know if you get better results with this.




              • 4. Re: Edison RS-485 library

                It helps, no compilation error.

                Great thanks.

                Now I have connection error.

                I want to use function 03-ReadHoldingRegistaers according to Modbus RTU protocol.

                There is a string " int result =  node.readHoldingRegisters(address, bytesQty);" in one example,

                but no parity bit and stop bit.

                • 5. Re: Edison RS-485 library

                  Hi NY


                  Could you post the example you are trying to run ?

                  How are you testing this? Are you using another instrument or do you only have the RS485 shield connected in the other side?

                  What do you mean with "but no parity bit and stop bit" ? Do you need these parameters to work with the shield?