Reading data from LG5310 energy meter using modbus protocols

[lraja33]

I am stuck with reading data from my energy meter for about a month. I have tried many things/programs. But still cannot read data till now. I seek your help.
Thank you.

By the way, I am using Arduino mega 2650. and trying to read ELmeasure meter(LG5310).
From Modbus tester software I am getting results successfully.

Kindly check my code here,

#include <ModbusMaster.h>


#define MAX485_DE      3
#define MAX485_RE_NEG  2

// instantiate ModbusMaster object
ModbusMaster node;

void preTransmission()
{
  digitalWrite(MAX485_RE_NEG, 1);
  digitalWrite(MAX485_DE, 1);
}

void postTransmission()
{
  digitalWrite(MAX485_RE_NEG, 0);
  digitalWrite(MAX485_DE, 0);
}

void setup()
{
  pinMode(MAX485_RE_NEG, OUTPUT);
  pinMode(MAX485_DE, OUTPUT);
  // Init in receive mode

  digitalWrite(MAX485_RE_NEG, 0);
  digitalWrite(MAX485_DE, 0);

  // Modbus communication runs at 9600 baud
  Serial.begin(9600);
Serial1.begin(9600,SERIAL_8N1);
  // Modbus slave ID 1
  node.begin(1, Serial1);
  // Callbacks allow us to configure the RS485 transceiver correctly
  node.preTransmission(preTransmission);
  node.postTransmission(postTransmission);
}

void loop()
{
  float result;

  result = node.readInputRegisters(40156, 2);
  if (result == node.ku8MBSuccess)
  {

    
    Serial.println(node.getResponseBuffer(0x01));

   
    Serial.println(node.getResponseBuffer(0x02));
    
    
  }
  delay(1000);
}

Now im trying to read holding registers value in arduino and display it in serial monitor but in serial monitor the output is always zero.

kINDLY DO THE NEEDFUL

[wildbill]

Try a different register. Your test software (oddly) doesn't appear to show any data for even numbered registers.

[markd833]

@lraja33

result = node.readInputRegisters(40156, 2);

I'm going from memory here, but @pylon will probably have a better answer than me ....

When you see address 40156 the actual address you want to put in the function call is either 155 or 157 (sorry, can't recall if you add 1 or subtract 1!).

[noiasca]

@lraja33

40156

use 40156-40001 = 155,
then read two bytes.