16 bit values over modbusTCP

Projects Programming
1

I need to send a 16 bit volatile control word to a drive over modbus tcp.

I am struggling to get the code right and would appreciate some help please....

I am testing the modbus output by sending a value from the arduino to my pc which is running modbus slave software but I am getting the wrong value back.

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uint16_t myValue = 49152; // Example 16-bit value

  // Split the 16-bit value into two 8-bit values
  byte highByte = (myValue >> 8) & 0xFF;
  byte lowByte = myValue & 0xFF;


    if (!modbusTCPClient.holdingRegisterWrite(0x00,(1, highByte)) || (0x00,(1, lowByte))) {
      Serial.print("Failed to write coil! ");
      Serial.println(modbusTCPClient.lastError());
    }
2

holdingRegisterWrite takes an uint16_t.
modbus registers are 16 bit