Nano_Modbus_Pyranometer_ID

#include <SoftwareSerial.h>
#include <ModbusMaster.h>

// Pin definitions (RX = D2 to RO, TX = D3 to DI)
#define RX_PIN 2
#define TX_PIN 3

// Communication settings
#define CURRENT_SLAVE_ID  1      // The address the sensor currently responds to
#define NEW_SLAVE_ID      2      // The new address you want to assign (1 - 247)
#define BUS_BAUD_RATE     4800   // Current bus baud rate (4800 or 9600)

// Renke EEPROM Address Register
#define RENKE_REG_ADDR    0x07D0

SoftwareSerial modbusSerial(RX_PIN, TX_PIN);
ModbusMaster node;

void setup() {
  Serial.begin(9600);
  while (!Serial);
  delay(500);

  Serial.println("--- Renke Slave ID Configurator ---");

  modbusSerial.begin(BUS_BAUD_RATE);
  node.begin(CURRENT_SLAVE_ID, modbusSerial);

  delay(200);

  Serial.print("Changing Slave ID from ");
  Serial.print(CURRENT_SLAVE_ID);
  Serial.print(" to ");
  Serial.print(NEW_SLAVE_ID);
  Serial.print("... ");

  uint8_t result = node.writeSingleRegister(RENKE_REG_ADDR, NEW_SLAVE_ID);

  if (result == node.ku8MBSuccess) {
    Serial.println("SUCCESS!");
    Serial.println("Power cycle the 12V supply to finalize the address change.");
  } else {
    Serial.print("FAILED - Error: 0x");
    Serial.println(result, HEX);
  }
}

void loop() {
  // Setup runs once
}