Change SLAVE ADDRESS during void setup

[pietrozanc]

Hi guys, what i would like to do is change the SLAVE_ID during the void setup. This because i would like to set the slave address with 5 dip switch. At the moment the SLAVE_ID is declared at the beginning and i don't kwon how to solve this problem.
The SLAVE_DIP is the int variable that i want to use as a SLAVE_ID

Below my code:

//Testato con QModMaster
//https://github.com/yaacov/ArduinoModbusSlave

// https://en.wikipedia.org/wiki/Modbus

#include <ModbusSlave.h>
#include <SoftwareSerial.h>
SoftwareSerial RS485Serial(10, 11); // RX, TX

#define SLAVE_ID 10           // The Modbus slave ID, change to the ID you want to use.
#define SERIAL_BAUDRATE 9600 // Change to the baudrate you want to use for Modbus communication.
// Comment out the following line if your not using RS485
#define RS485_CTRL_PIN 2 // Change to the pin the RE/DE pin of the RS485 controller is connected to.

#define command_open 8  
#define command_close 9  
#define command_rocking 12

#define feedback_open 3
#define feedback_close 4  
#define WatchDog 5

#define DIP_1 A0
#define DIP_2 A1
#define DIP_3 A2
#define DIP_4 A3
#define DIP_5 A4

boolean SET_1;
boolean SET_2;
boolean SET_3;
boolean SET_4;
boolean SET_5;


// Modbus object declaration
Modbus slave(RS485Serial, SLAVE_ID, RS485_CTRL_PIN);

void setup() {

    // RS485 control pin must be output
    pinMode(2, OUTPUT);

    //OUTPUT
    pinMode(command_open, OUTPUT);
    pinMode(command_close, OUTPUT);
    pinMode(command_rocking, OUTPUT);

    //INPUT
    pinMode(feedback_open, INPUT);
    pinMode(feedback_close, INPUT);
    pinMode(WatchDog, INPUT);

    //DIPSWITCH
    pinMode(DIP_1, INPUT);
    pinMode(DIP_2, INPUT);
    pinMode(DIP_3, INPUT);
    pinMode(DIP_4, INPUT);
    pinMode(DIP_5, INPUT);

    SET_1 = digitalRead(DIP_1);
    SET_2 = digitalRead(DIP_2);
    SET_3 = digitalRead(DIP_3);
    SET_4 = digitalRead(DIP_4);
    SET_5 = digitalRead(DIP_5);

    int SLAVE_DIP = (SET_1*1)+(SET_2*2)+(SET_3*4)+(SET_4*8)+(SET_5*16)+1;
    Serial.println(SLAVE_DIP);

    // Register functions to call when a certain function code is received.
    slave.cbVector[CB_WRITE_COILS] = writeDigitalOut;
    slave.cbVector[CB_READ_DISCRETE_INPUTS] = readDigitalIn;
    
    // Set the serial port and slave to the given baudrate.
    RS485Serial.begin(SERIAL_BAUDRATE);
    slave.begin(SERIAL_BAUDRATE);
    Serial.begin(9600);
}

void loop() {
    /* listen for modbus commands con serial port.
     *
     * on a request, handle the request.
     * if the request has a user handler function registered in cbVector.
     * call the user handler function.
     */ 
    slave.poll();
}


/**
 * Handle Force Single Coil (FC=05) and Force Multiple Coils (FC=15)
 * set digital output pins (coils).
 * 
 * Dalla pagina di wikipedia addr: Coil  Read-write  1 bit   00001 - 09999 
 */
uint8_t writeDigitalOut(uint8_t fc, uint16_t address, uint16_t length) {
  Serial.print("FC= ");
  Serial.println(fc);
  Serial.print("ADDRES= ");
  Serial.println(address);
  Serial.print("LENGHT= ");
  Serial.println(length);

  if (address == 3) {
    digitalWrite(command_open, slave.readCoilFromBuffer(0));

    digitalWrite(command_close, slave.readCoilFromBuffer(1));

    digitalWrite(command_rocking, slave.readCoilFromBuffer(2));
  }

    return STATUS_OK;
}


// Handle the function code Read Input Status (FC=02) and write back the values from the digital input pins (discreet input).
uint8_t readDigitalIn(uint8_t fc, uint16_t address, uint16_t length)
{       
  Serial.print("FC= ");
  Serial.println(fc);
  Serial.print("ADDRES= ");
  Serial.println(address);
  Serial.print("LENGHT= ");
  Serial.println(length);


  if (address == 0) {
    // Write the state of the digital pin to the response buffer.
        slave.writeCoilToBuffer(0, digitalRead(feedback_open));

    // Write the state of the digital pin to the response buffer.
        slave.writeCoilToBuffer(1, digitalRead(feedback_close));

    // Write the state of the digital pin to the response buffer.
        slave.writeCoilToBuffer(2, digitalRead(WatchDog));
  }
  
    return STATUS_OK;
}

Thanks
Pietro

[yaacov]

did you try setUnitAddress ?
https://github.com/yaacov/ArduinoModbusSlave/blob/master/src/ModbusSlave.h#L110