Announcement

Collapse
No announcement yet.

Raspberry pi and MODBUS

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts


  • Raspberry pi and MODBUS

    I have a Pi putting data out to a holding register at 1000, to a Domore. Can the do more do this? Can it contain the registers? If so have to I figure out where?

    Thanks


  • #2
    Sure. It'll be in MHR1000.

    Comment



    • #3
      Are the MHR the same as other types? Like being the same as V1000?

      Comment



      • #4
        The V block is 16 bit unsigned integer, and the two numeric Modbus server blocks (MIR and MHR) are both 16 bit signed integers, but basically yes.

        Comment



        • #5
          If your question is if it's like DL where the Modbus Addresses are MAPPED to V, they are NOT mapped. V1000 is a different register than MHR1000. V block is a different data block than MHR data block. They are the same "data type", that is they are both blocks of 16 bit integer, but different memory locations.
          There are 10 kinds of people in this world, those who know binary, and those who do not.

          Comment



          • #6
            Yea, thatís what I was getting at.

            Comment



            • #7
              Is there some weird translation between the pi 1000 and domore 1000? Not seeing it show up on the domore.

              Comment



              • #8
                Originally posted by trimixdiver1 View Post
                Is there some weird translation between the pi 1000 and domore 1000? Not seeing it show up on the domore.
                No. If the master is writing to Modbus Holding Register 1000 in the Do-more, the data will show up in MHR1000. If this is Modbus/TCP, you could perhaps do a Wireshark capture and I could tell you what's going on.

                If you want to convince yourself Do-more is working right, do an MWX with the @IntModTCPClient device, to IP Address 127.0.0.1 (local loopback address), choose function code 16 - Write Multiple Registers, specify Modbus Offset Address 1000, and pick any source register or constant. Enable the box, and the data will show up in MHR1000.

                Comment

                Working...
                X