Sending data through MODBUS master using ModbusRTU library on Arduino Uno

Hey,
I am trying to send int type data through MODBUS with arduino uno acting as the master and a slave MODBUS simulator on my PC. Communication is working but the data i am sending is not right. Even though the value of temp1, temp2, etc is correct, it is not being sent correctly. Any suggestions or advice would be really helpful
Below is the code


#include <ModbusRtu.h>

//#include <SimpleModbusMaster.h>

//#include <ModbusRTUMaster.h>
//#include<RS485.h>

//#include <ArduinoModbus.h>
//#include <ArduinoRS485.h>

#include <Timer.h>
#include <Event.h>


#include<ezButton.h>

//Pin definitions
#define PowerOnOffButtonPin 3
#define StatusLED1 4
#define StatusLED2 5
#define StatusLED3 6
#define StatusLED4 7
#define StatusLED5 8

#define T1 A0
#define T2 A1
#define T3 A2
#define T4 A3
#define T5 A4
#define T6 A5
#define T7 A6
#define T8 A7

// Definitions for temperature
#define T_REF 25.0
#define DEG_K 273.16
#define THERM_BETA 3435.0
#define c1 1.009249522e-03 
#define c2 2.378405444e-04 
#define c3 2.019202697e-07
#define SERIES_RESISTOR 21020

//different MODBUS libraries to use
#define MODBUS_1 1    // include ModbusRtu.h
#define MODBUS_2 0    // include SimpleModbusMaster.h
#define MODBUS_3 0    // include ModbusRTUMaster.h and RS485.h
#define MODBUS_4 0    //include ArduinoModbus.h and ArduinoRS485.h

#if MODBUS_1 || MODBUS_2 || MODBUS_3 || MODBUS_4
#define AUX_ADDRESS 0
#define BMS_ADDRESS 0x31

#define AUX_STATE_VARIABLES_REGISTER 0x31
#define AUX_SYSTEM_STATUS_REGISTER 0x032
#define AUX_DISCHARGE_ONOFF_REGISTER 0x33
#define AUX_TEMP_1_REGISTER 0x35
#define AUX_TEMP_2_REGISTER 0x37
#define AUX_TEMP_3_REGISTER 0x39
#define AUX_TEMP_4_REGISTER 0x3B
#define AUX_TEMP_5_REGISTER 0x3D
#define AUX_TEMP_6_REGISTER 0x3F
#define AUX_TEMP_7_REGISTER 0x41
#define AUX_TEMP_8_REGISTER 0x43

#define TOTAL_NO_OF_REGISTERS 11

#define RS485_TX_EN_PIN 2
#define baud 19200
#endif

#if MODBUS_2
#define timeout 1000
#define polling 200 // the scan rate
#define retry_count 10

enum
{
  PACKET1,
  PACKET2,
  TOTAL_NO_OF_PACKETS
};

Packet packets[TOTAL_NO_OF_PACKETS];
//Master register array
unsigned int regs[TOTAL_NO_OF_REGISTERS];
#endif

#if MODBUS_3
ModbusRTUMaster master(RS485);
#endif


const int shortPressTime = 800;                //max time considered for a short press
const int longPressTime = 3000;                //min time considered for a long press 

int buttonLastState = LOW;
int buttonCurrentState;

unsigned long pressedTime = 0;
unsigned long releasedTime = 0;

float soc;
float temp1,temp2,temp3,temp4,temp5,temp6,temp7,temp8;
float V1,V2,V3,V4,V5,V6,V7,V8;
int R1,R2,R3,R4,R5,R6,R7,R8;
int tempSensorValue1,tempSensorValue2,tempSensorValue3,tempSensorValue4,tempSensorValue5,tempSensorValue6,tempSensorValue7,tempSensorValue8;

//float c1 = 1.009249522e-03, c2 = 2.378405444e-04, c3 = 2.019202697e-07;

bool isCharging = false;                 // is true if pack is charging(Ich > 0 )
bool dischargeMosfetStatus = false;      // is true if discharge MOSFET is ON

ezButton powerOnOffSwitch(PowerOnOffButtonPin);
Timer secondsTimer;

#if MODBUS_1
Modbus master(AUX_ADDRESS, Serial, RS485_TX_EN_PIN);
//uint16_t modbusData[16];
uint16_t state[TOTAL_NO_OF_REGISTERS] = {0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B};
uint8_t u8state;
uint8_t u8query;
modbus_t telegram[TOTAL_NO_OF_REGISTERS];
unsigned long u32wait;
#endif


#if MODBUS_4
uint16_t state[TOTAL_NO_OF_REGISTERS] = {0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B};
#endif


/****************************** Function Declarations    ***********************/
void interruptRoutine();
void showSoC();
void showChargingStatus();
void calculateTemperatures();
void serialFlush();
void modbus_setup();
void modbusLoop();





/****************************** Main Function Definitions    ***********************/
void setup() {
  Serial.begin(baud);
  
  pinMode(StatusLED1,OUTPUT);
  pinMode(StatusLED2,OUTPUT);
  pinMode(StatusLED3,OUTPUT);
  pinMode(StatusLED4,OUTPUT);
  pinMode(StatusLED5,OUTPUT);
  
  pinMode(PowerOnOffButtonPin, INPUT_PULLUP);
  powerOnOffSwitch.setDebounceTime(50);

  //attachInterrupt(digitalPinToInterrupt(PowerOnOffButtonPin),interruptRoutine,FALLING);
  
  modbus_setup();
}

void loop() {
  //modbusLoop();
  //modbus_update();
  powerOnOffSwitch.loop();
  secondsTimer.update();
  //buttonCurrentState = digitalRead(PowerOnOffButtonPin);

  if(!isCharging)
  {
    if(powerOnOffSwitch.isPressed())        // button is pressed
      {
        pressedTime = millis();
      }
    else if(powerOnOffSwitch.isReleased()) // button is released
      { 
        releasedTime = millis();
        long pressDuration = releasedTime - pressedTime;

        if( pressDuration < shortPressTime )
        {
          soc = 88.43;
          showSoC();
          delay(100);
          Serial.println("A short press is detected");
        }
      
        if( pressDuration > longPressTime )
        {
          Serial.println("A long press is detected");
          state[AUX_DISCHARGE_ONOFF_REGISTER] = true;
          if(dischargeMosfetStatus)
          {
            //Serial.println("A long press is detected");
            secondsTimer.oscillate(StatusLED5,1000, LOW, 3);
            secondsTimer.oscillate(StatusLED1,1000, LOW, 3);
            delay(100);
          }
        }
      }
  }

  modbusLoop();
    
  //analog read for thermistor temperature readings
  tempSensorValue1 = analogRead(T1);
  tempSensorValue2 = analogRead(T2);
  tempSensorValue3 = analogRead(T3);
  tempSensorValue4 = analogRead(T4);
  tempSensorValue5 = analogRead(T5);
  tempSensorValue6 = analogRead(T6);
  tempSensorValue7 = analogRead(T7);
  tempSensorValue8 = analogRead(T8);
  
  calculateTemperatures();
  //Serial.print("Temp4 :");
  //Serial.println(temp4);
  
  delay(150);

  //modbusData[4] = (int)temp4;
//  #if MODBUS_1
//  state[AUX_TEMP_1_REGISTER] = (int)temp1;
//  state[AUX_TEMP_2_REGISTER] = (int)temp2;
//  state[AUX_TEMP_3_REGISTER] = (int)temp3;
//  state[AUX_TEMP_4_REGISTER] = (int)temp4;
//  state[AUX_TEMP_5_REGISTER] = (int)temp5;
//  state[AUX_TEMP_6_REGISTER] = (int)temp6;
//  state[AUX_TEMP_7_REGISTER] = (int)temp7;
//  state[AUX_TEMP_8_REGISTER] = (int)temp8;
//  #endif
  //Serial.println(state[AUX_TEMP_4_REGISTER]);
  delay(50);

  //Serial.println(state[AUX_TEMP_3TO4_REGISTER]);
  if(isCharging)
  {
    soc = 72;
    showChargingStatus();
  }
  
  //buttonLastState = buttonCurrentState;
  serialFlush();
}



void interruptRoutine()
{
  
}

void showSoC()
{
  if(soc >= 90.0)
  {
    digitalWrite(StatusLED5,HIGH);
    digitalWrite(StatusLED4,HIGH);
    digitalWrite(StatusLED3,HIGH);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);
  }
  else if(soc < 90.0 && soc >= 70.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,HIGH);
    digitalWrite(StatusLED3,HIGH);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);    
  }
  else if(soc< 70.0 && soc >= 50.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,HIGH);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);    
  }
  else if(soc< 50.0 && soc >= 30.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,LOW);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);     
  }
  else if(soc < 30.0 && soc >= 10.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,LOW);
    digitalWrite(StatusLED2,LOW);
    digitalWrite(StatusLED1,HIGH);     
  }
  else if(soc < 10.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,LOW);
    digitalWrite(StatusLED2,LOW);
    digitalWrite(StatusLED1,LOW);
  }

  delay(1000);
  
  digitalWrite(StatusLED5,LOW);
  digitalWrite(StatusLED4,LOW);
  digitalWrite(StatusLED3,LOW);
  digitalWrite(StatusLED2,LOW);
  digitalWrite(StatusLED1,LOW);  
}

void showChargingStatus()
{
  if(isCharging)
  {
    if(soc>0.0 && soc <= 30.0)
    {
      digitalWrite(StatusLED1,HIGH);
      delay(250);
      digitalWrite(StatusLED1,LOW);
      digitalWrite(StatusLED2,LOW);
      digitalWrite(StatusLED3,LOW);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW);    
    }
    else if (soc > 30.0 && soc <= 50.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      delay(250);
      digitalWrite(StatusLED2,LOW);
      digitalWrite(StatusLED3,LOW);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW); 
    }
    else if (soc > 50.0 && soc <= 70)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      delay(250);
      digitalWrite(StatusLED3,LOW);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW);    
    }
    else if(soc > 70.0 && soc <= 90.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      digitalWrite(StatusLED4,HIGH);
      delay(250);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW);     
    }
    else if( soc > 90.0 && soc < 100.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      digitalWrite(StatusLED4,HIGH);
      digitalWrite(StatusLED5,HIGH);
      delay(250);
      digitalWrite(StatusLED5,LOW);     
    }
    else if (soc == 100.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      digitalWrite(StatusLED4,HIGH);
      digitalWrite(StatusLED5,HIGH);     
    }
  }
}

void calculateTemperatures()
{
  R1 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue1) - 1.0);
  R2 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue2) - 1.0);
  R3 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue3) - 1.0);
  R4 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue4) - 1.0);
  R5 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue5) - 1.0);
  R6 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue6) - 1.0);
  R7 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue7) - 1.0);
  R8 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue8) - 1.0);

  temp1 = (1.0 / (c1 + c2*log(R1) + c3*log(R1)*log(R1)*log(R1))) - DEG_K;
  temp2 = (1.0 / (c1 + c2*log(R2) + c3*log(R2)*log(R2)*log(R2))) - DEG_K;
  temp3 = (1.0 / (c1 + c2*log(R3) + c3*log(R3)*log(R3)*log(R3))) - DEG_K;
  temp4 = (1.0 / (c1 + c2*log(R4) + c3*log(R4)*log(R4)*log(R4))) - DEG_K;
  temp5 = (1.0 / (c1 + c2*log(R5) + c3*log(R5)*log(R5)*log(R5))) - DEG_K;
  temp6 = (1.0 / (c1 + c2*log(R6) + c3*log(R6)*log(R6)*log(R6))) - DEG_K;  
  temp7 = (1.0 / (c1 + c2*log(R7) + c3*log(R7)*log(R7)*log(R7))) - DEG_K;
  temp8 = (1.0 / (c1 + c2*log(R8) + c3*log(R8)*log(R8)*log(R8))) - DEG_K;
  
}


void serialFlush()
{
  while(Serial.available()>0)
    char t = Serial.read();
}

void modbus_setup()
{
  #if MODBUS_1 
//  state[AUX_STATE_VARIABLES_REGISTER] = 0;
//  state[AUX_SYSTEM_STATUS_REGISTER] = 0;
//  state[AUX_DISCHARGE_ONOFF_REGISTER] = 0;
//  state[AUX_TEMP_1TO2_REGISTER] = 0;
//  state[AUX_TEMP_3TO4_REGISTER] = 0;
//  state[AUX_TEMP_5TO6_REGISTER] = 0;
//  state[AUX_TEMP_7TO8_REGISTER] = 0;
   
  telegram[0].u8id = BMS_ADDRESS; // slave address
  telegram[0].u8fct = 4; // function code (this one is registers read)
  telegram[0].u16RegAdd = 0; // start address in slave
  telegram[0].u16CoilsNo = 4; // number of elements (coils or registers) to read
  telegram[0].au16reg = state[AUX_STATE_VARIABLES_REGISTER]; // pointer to a memory array in the Arduino

  telegram[1].u8id = BMS_ADDRESS; // slave address
  telegram[1].u8fct = 4; // function code (this one is registers read)
  telegram[1].u16RegAdd = 0; // start address in slave
  telegram[1].u16CoilsNo = 4; // number of elements (coils or registers) to read
  telegram[1].au16reg = state[AUX_SYSTEM_STATUS_REGISTER]; // pointer to a memory array in the Arduino

  telegram[2].u8id = BMS_ADDRESS; // slave address
  telegram[2].u8fct = 6; // function code (this one is registers read)
  telegram[2].u16RegAdd = 0; // start address in slave
  telegram[2].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[2].au16reg = state[AUX_DISCHARGE_ONOFF_REGISTER]; // pointer to a memory array in the Arduino

  telegram[3].u8id = BMS_ADDRESS; // slave address
  telegram[3].u8fct = 6; // function code (this one is single coil write)
  telegram[3].u16RegAdd = 1; // start address in slave
  telegram[3].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[3].au16reg = state[AUX_TEMP_1_REGISTER]; // pointer to a memory array in the Arduino

  telegram[4].u8id = BMS_ADDRESS; // slave address
  telegram[4].u8fct = 6; // function code (this one is single coil write)
  telegram[4].u16RegAdd = 2; // start address in slave
  telegram[4].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[4].au16reg = state[AUX_TEMP_2_REGISTER]; // pointer to a memory array in the Arduino  

  telegram[5].u8id = BMS_ADDRESS; // slave address
  telegram[5].u8fct = 6; // function code (this one is single coil write)
  telegram[5].u16RegAdd = 3; // start address in slave
  telegram[5].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[5].au16reg = state[AUX_TEMP_3_REGISTER]; // pointer to a memory array in the Arduino

  telegram[6].u8id = BMS_ADDRESS; // slave address
  telegram[6].u8fct = 6; // function code (this one is single coil write)
  telegram[6].u16RegAdd = 4; // start address in slave
  telegram[6].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[6].au16reg = state[AUX_TEMP_4_REGISTER]; // pointer to a memory array in the Arduino

  telegram[7].u8id = BMS_ADDRESS; // slave address
  telegram[7].u8fct = 6; // function code (this one is single coil write)
  telegram[7].u16RegAdd = 5; // start address in slave
  telegram[7].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[7].au16reg = state[AUX_TEMP_5_REGISTER]; // pointer to a memory array in the Arduino

  telegram[8].u8id = BMS_ADDRESS; // slave address
  telegram[8].u8fct = 6; // function code (this one is single coil write)
  telegram[8].u16RegAdd = 6; // start address in slave
  telegram[8].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[8].au16reg = state[AUX_TEMP_6_REGISTER]; // pointer to a memory array in the Arduino    


  telegram[9].u8id = BMS_ADDRESS; // slave address
  telegram[9].u8fct = 6; // function code (this one is registers read)
  telegram[9].u16RegAdd = 7; // start address in slave
  telegram[9].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[9].au16reg = state[AUX_TEMP_7_REGISTER]; // pointer to a memory array in the Arduino
  
  // telegram 10: write a single coil
  telegram[10].u8id = BMS_ADDRESS; // slave address
  telegram[10].u8fct = 6; // function code (this one is write a single register)
  telegram[10].u16RegAdd = 8; // start address in slave
  telegram[10].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[10].au16reg =  state[AUX_TEMP_8_REGISTER]; // pointer to a memory array in the Arduino

  master.start();
  master.setTimeOut( 5000 ); // if there is no answer in 5000 ms, roll over
  u32wait = millis() + 1000;
  u8state = u8query = 0; 
  #endif
  
  #if MODBUS_2
// Initialize each packet: packet, slave-id, function, start of slave index, number of regs, start of master index

  modbus_construct(&packets[PACKET1], BMS_ADDRESS, READ_HOLDING_REGISTERS, 0,TOTAL_NO_OF_REGISTERS, 0);
  modbus_construct(&packets[PACKET2], BMS_ADDRESS, PRESET_MULTIPLE_REGISTERS, 1, TOTAL_NO_OF_REGISTERS, 0);
  modbus_configure(&Serial, baud, SERIAL_8N1, timeout, polling, retry_count,RS485_TX_EN_PIN, packets, TOTAL_NO_OF_PACKETS, regs);
  
  #endif

  #if MODBUS_4
  pinMode(RS485_TX_EN_PIN, OUTPUT);
  ModbusRTUServer.begin(BMS_ADDRESS, baud);
  ModbusRTUServer.configureHoldingRegisters(0x61, TOTAL_NO_OF_REGISTERS);
  ModbusRTUServer.configureInputRegisters(0x61, TOTAL_NO_OF_REGISTERS);
  #endif
}



void modbusLoop()
{
  #if MODBUS_2
  modbus_update();
  #endif
  
  
  #if MODBUS_1
  switch( u8state ) {
  case 0: 
    if (millis() > u32wait) u8state++; // wait state
    break;
  case 1: 
    master.query( telegram[u8query] ); // send query (only once)
    u8state++;
    u8query++;
    if (u8query > TOTAL_NO_OF_REGISTERS) u8query = 0;
      break;
  case 2:
    //Serial.println(state[AUX_TEMP_4_REGISTER]);    
    master.poll(); // check incoming messages
    if (master.getState() == COM_IDLE) {
      u8state = 0;
      u32wait = millis() + 1000; 
    }
    break;

  state[AUX_TEMP_1_REGISTER] = (int)temp1;
  state[AUX_TEMP_2_REGISTER] = (int)temp2;
  state[AUX_TEMP_3_REGISTER] = (int)temp3;
  state[AUX_TEMP_4_REGISTER] = (int)temp4;
  state[AUX_TEMP_5_REGISTER] = (int)temp5;
  state[AUX_TEMP_6_REGISTER] = (int)temp6;
  state[AUX_TEMP_7_REGISTER] = (int)temp7;
  state[AUX_TEMP_8_REGISTER] = (int)temp8;

  }
  #endif

  #if MODBUS_4
  ModbusRTUServer.poll();
  
  state[AUX_TEMP_1_REGISTER] = (int)temp1;
  state[AUX_TEMP_2_REGISTER] = (int)temp2;
  state[AUX_TEMP_3_REGISTER] = (int)temp3;
  state[AUX_TEMP_4_REGISTER] = (int)temp4;
  state[AUX_TEMP_5_REGISTER] = (int)temp5;
  state[AUX_TEMP_6_REGISTER] = (int)temp6;
  state[AUX_TEMP_7_REGISTER] = (int)temp7;
  state[AUX_TEMP_8_REGISTER] = (int)temp8;

  digitalWrite(RS485_TX_EN_PIN, HIGH);
  delay(10);
  ModbusRTUServer.holdingRegisterWrite(0x01, state[AUX_TEMP_1_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x02, state[AUX_TEMP_2_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x03, state[AUX_TEMP_3_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x04, state[AUX_TEMP_4_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x05, state[AUX_TEMP_5_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x06, state[AUX_TEMP_6_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x07, state[AUX_TEMP_7_REGISTER]);
  ModbusRTUServer.holdingRegisterWrite(0x08, state[AUX_TEMP_8_REGISTER]);
  
  for (int i = 0; i < TOTAL_NO_OF_REGISTERS; i++)
  {
    long holdingRegisterValue = ModbusRTUServer.holdingRegisterRead(i);
    ModbusRTUServer.inputRegisterWrite(i, holdingRegisterValue);
  }

  #endif

  
}

Sorry, this code is a mess! Remove all versions that are not in use and post again. This might be handy for you but is a nightmare for someone trying to find your error.

Alright, here is the code with what is being used.


#include <ModbusRtu.h>

#include <Timer.h>
#include <Event.h>


#include<ezButton.h>

//Pin definitions
#define PowerOnOffButtonPin 3
#define StatusLED1 4
#define StatusLED2 5
#define StatusLED3 6
#define StatusLED4 7
#define StatusLED5 8

#define T1 A0
#define T2 A1
#define T3 A2
#define T4 A3
#define T5 A4
#define T6 A5
#define T7 A6
#define T8 A7

// Definitions for temperature
#define T_REF 25.0
#define DEG_K 273.16
#define THERM_BETA 3435.0
#define c1 1.009249522e-03 
#define c2 2.378405444e-04 
#define c3 2.019202697e-07
#define SERIES_RESISTOR 21020

//different MODBUS libraries to use
#define MODBUS_1 1    // include ModbusRtu.h

#if MODBUS_1 || MODBUS_2 || MODBUS_3 || MODBUS_4
#define AUX_ADDRESS 0
#define BMS_ADDRESS 0x31

#define AUX_STATE_VARIABLES_REGISTER 0x01
#define AUX_SYSTEM_STATUS_REGISTER 0x02
#define AUX_DISCHARGE_ONOFF_REGISTER 0x03
#define AUX_TEMP_1_REGISTER 0x04
#define AUX_TEMP_2_REGISTER 0x05
#define AUX_TEMP_3_REGISTER 0x06
#define AUX_TEMP_4_REGISTER 0x07
#define AUX_TEMP_5_REGISTER 0x08
#define AUX_TEMP_6_REGISTER 0x09
#define AUX_TEMP_7_REGISTER 0x0A
#define AUX_TEMP_8_REGISTER 0x0B

#define TOTAL_NO_OF_REGISTERS 11

#define RS485_TX_EN_PIN 2
#define baud 19200
#endif

const int shortPressTime = 800;                //max time considered for a short press
const int longPressTime = 3000;                //min time considered for a long press 

unsigned long pressedTime = 0;
unsigned long releasedTime = 0;

float soc;
float temp1,temp2,temp3,temp4,temp5,temp6,temp7,temp8;
float V1,V2,V3,V4,V5,V6,V7,V8;
int R1,R2,R3,R4,R5,R6,R7,R8;
int tempSensorValue1,tempSensorValue2,tempSensorValue3,tempSensorValue4,tempSensorValue5,tempSensorValue6,tempSensorValue7,tempSensorValue8;


bool isCharging = false;                 // is true if pack is charging(Ich > 0 )
bool dischargeMosfetStatus = false;      // is true if discharge MOSFET is ON
bool buttonStatusFlag = false;

ezButton powerOnOffSwitch(PowerOnOffButtonPin);
Timer secondsTimer;

#if MODBUS_1
Modbus master(AUX_ADDRESS, Serial, RS485_TX_EN_PIN);
uint16_t state[TOTAL_NO_OF_REGISTERS];
uint8_t u8state;
uint8_t u8query;
modbus_t telegram[TOTAL_NO_OF_REGISTERS];
unsigned long u32wait;
#endif



/****************************** Function Declarations    ***********************/
void interruptRoutine();
void showSoC();
void showChargingStatus();
void calculateTemperatures();
void serialFlush();
void modbus_setup();
void modbusLoop();





/****************************** Main Function Definitions    ***********************/
void setup() {
  Serial.begin(baud);
  
  pinMode(StatusLED1,OUTPUT);
  pinMode(StatusLED2,OUTPUT);
  pinMode(StatusLED3,OUTPUT);
  pinMode(StatusLED4,OUTPUT);
  pinMode(StatusLED5,OUTPUT);
  
  pinMode(PowerOnOffButtonPin, INPUT_PULLUP);
  powerOnOffSwitch.setDebounceTime(50);

  attachInterrupt(digitalPinToInterrupt(PowerOnOffButtonPin),interruptRoutine,FALLING);
  
  modbus_setup();
}

void loop() {

  powerOnOffSwitch.loop();
  secondsTimer.update();
  if(buttonStatusFlag)
  {
    if(!isCharging)
    {
      if(powerOnOffSwitch.isPressed())        // button is pressed
        {
          pressedTime = millis();
        }
      else if(powerOnOffSwitch.isReleased()) // button is released
        { 
          releasedTime = millis();
          long pressDuration = releasedTime - pressedTime;

          if( pressDuration < shortPressTime )
          {
            soc = 88.43;
            showSoC();
            delay(100);
            Serial.println("A short press is detected");
          }
      
          if( pressDuration > longPressTime )
          {
            Serial.println("A long press is detected");
            state[AUX_DISCHARGE_ONOFF_REGISTER] = true;
            if(dischargeMosfetStatus)
            {
              //Serial.println("A long press is detected");
              secondsTimer.oscillate(StatusLED5,1000, LOW, 3);
              secondsTimer.oscillate(StatusLED1,1000, LOW, 3);
              delay(100);
            }
          }
        }
    }
  }

  modbusLoop();
    
  //analog read for thermistor temperature readings
  tempSensorValue1 = analogRead(T1);
  tempSensorValue2 = analogRead(T2);
  tempSensorValue3 = analogRead(T3);
  tempSensorValue4 = analogRead(T4);
  tempSensorValue5 = analogRead(T5);
  tempSensorValue6 = analogRead(T6);
  tempSensorValue7 = analogRead(T7);
  tempSensorValue8 = analogRead(T8);
  
  calculateTemperatures();
  
  delay(150);

  if(isCharging)
  {
    soc = 72;
    showChargingStatus();
  }
 
  serialFlush();
}



void interruptRoutine()
{
  buttonStatusFlag = true;
  
}

void showSoC()
{
  if(soc >= 90.0)
  {
    digitalWrite(StatusLED5,HIGH);
    digitalWrite(StatusLED4,HIGH);
    digitalWrite(StatusLED3,HIGH);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);
  }
  else if(soc < 90.0 && soc >= 70.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,HIGH);
    digitalWrite(StatusLED3,HIGH);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);    
  }
  else if(soc< 70.0 && soc >= 50.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,HIGH);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);    
  }
  else if(soc< 50.0 && soc >= 30.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,LOW);
    digitalWrite(StatusLED2,HIGH);
    digitalWrite(StatusLED1,HIGH);     
  }
  else if(soc < 30.0 && soc >= 10.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,LOW);
    digitalWrite(StatusLED2,LOW);
    digitalWrite(StatusLED1,HIGH);     
  }
  else if(soc < 10.0)
  {
    digitalWrite(StatusLED5,LOW);
    digitalWrite(StatusLED4,LOW);
    digitalWrite(StatusLED3,LOW);
    digitalWrite(StatusLED2,LOW);
    digitalWrite(StatusLED1,LOW);
  }

  delay(1000);
  
  digitalWrite(StatusLED5,LOW);
  digitalWrite(StatusLED4,LOW);
  digitalWrite(StatusLED3,LOW);
  digitalWrite(StatusLED2,LOW);
  digitalWrite(StatusLED1,LOW);  
}

void showChargingStatus()
{
  if(isCharging)
  {
    if(soc>0.0 && soc <= 30.0)
    {
      digitalWrite(StatusLED1,HIGH);
      delay(250);
      digitalWrite(StatusLED1,LOW);
      digitalWrite(StatusLED2,LOW);
      digitalWrite(StatusLED3,LOW);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW);    
    }
    else if (soc > 30.0 && soc <= 50.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      delay(250);
      digitalWrite(StatusLED2,LOW);
      digitalWrite(StatusLED3,LOW);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW); 
    }
    else if (soc > 50.0 && soc <= 70)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      delay(250);
      digitalWrite(StatusLED3,LOW);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW);    
    }
    else if(soc > 70.0 && soc <= 90.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      digitalWrite(StatusLED4,HIGH);
      delay(250);
      digitalWrite(StatusLED4,LOW);
      digitalWrite(StatusLED5,LOW);     
    }
    else if( soc > 90.0 && soc < 100.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      digitalWrite(StatusLED4,HIGH);
      digitalWrite(StatusLED5,HIGH);
      delay(250);
      digitalWrite(StatusLED5,LOW);     
    }
    else if (soc == 100.0)
    {
      digitalWrite(StatusLED1,HIGH);
      digitalWrite(StatusLED2,HIGH);
      digitalWrite(StatusLED3,HIGH);
      digitalWrite(StatusLED4,HIGH);
      digitalWrite(StatusLED5,HIGH);     
    }
  }
}

void calculateTemperatures()
{
  R1 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue1) - 1.0);
  R2 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue2) - 1.0);
  R3 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue3) - 1.0);
  R4 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue4) - 1.0);
  R5 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue5) - 1.0);
  R6 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue6) - 1.0);
  R7 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue7) - 1.0);
  R8 = SERIES_RESISTOR *(1024.0 / float(tempSensorValue8) - 1.0);

  temp1 = (1.0 / (c1 + c2*log(R1) + c3*log(R1)*log(R1)*log(R1))) - DEG_K;
  temp2 = (1.0 / (c1 + c2*log(R2) + c3*log(R2)*log(R2)*log(R2))) - DEG_K;
  temp3 = (1.0 / (c1 + c2*log(R3) + c3*log(R3)*log(R3)*log(R3))) - DEG_K;
  temp4 = (1.0 / (c1 + c2*log(R4) + c3*log(R4)*log(R4)*log(R4))) - DEG_K;
  temp5 = (1.0 / (c1 + c2*log(R5) + c3*log(R5)*log(R5)*log(R5))) - DEG_K;
  temp6 = (1.0 / (c1 + c2*log(R6) + c3*log(R6)*log(R6)*log(R6))) - DEG_K;  
  temp7 = (1.0 / (c1 + c2*log(R7) + c3*log(R7)*log(R7)*log(R7))) - DEG_K;
  temp8 = (1.0 / (c1 + c2*log(R8) + c3*log(R8)*log(R8)*log(R8))) - DEG_K;
  
}


void serialFlush()
{
  while(Serial.available()>0)
    char t = Serial.read();
}

void modbus_setup()
{
  #if MODBUS_1 
   
  telegram[0].u8id = BMS_ADDRESS; // slave address
  telegram[0].u8fct = 4; // function code (this one is registers read)
  telegram[0].u16RegAdd = 10; // start address in slave
  telegram[0].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[0].au16reg = state[AUX_STATE_VARIABLES_REGISTER]; // pointer to a memory array in the Arduino

  telegram[1].u8id = BMS_ADDRESS; // slave address
  telegram[1].u8fct = 4; // function code (this one is registers read)
  telegram[1].u16RegAdd = 9; // start address in slave
  telegram[1].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[1].au16reg = state[AUX_SYSTEM_STATUS_REGISTER]; // pointer to a memory array in the Arduino

  telegram[2].u8id = BMS_ADDRESS; // slave address
  telegram[2].u8fct = 6; // function code (this one is registers read)
  telegram[2].u16RegAdd = 0; // start address in slave
  telegram[2].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[2].au16reg = state[AUX_DISCHARGE_ONOFF_REGISTER]; // pointer to a memory array in the Arduino

  telegram[3].u8id = BMS_ADDRESS; // slave address
  telegram[3].u8fct = 6; // function code (this one is single coil write)
  telegram[3].u16RegAdd = 1; // start address in slave
  telegram[3].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[3].au16reg = state[AUX_TEMP_1_REGISTER]; // pointer to a memory array in the Arduino

  telegram[4].u8id = BMS_ADDRESS; // slave address
  telegram[4].u8fct = 6; // function code (this one is single coil write)
  telegram[4].u16RegAdd = 2; // start address in slave
  telegram[4].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[4].au16reg = state[AUX_TEMP_2_REGISTER]; // pointer to a memory array in the Arduino  

  telegram[5].u8id = BMS_ADDRESS; // slave address
  telegram[5].u8fct = 6; // function code (this one is single coil write)
  telegram[5].u16RegAdd = 3; // start address in slave
  telegram[5].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[5].au16reg = state[AUX_TEMP_3_REGISTER]; // pointer to a memory array in the Arduino

  telegram[6].u8id = BMS_ADDRESS; // slave address
  telegram[6].u8fct = 6; // function code (this one is single coil write)
  telegram[6].u16RegAdd = 4; // start address in slave
  telegram[6].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[6].au16reg = state[AUX_TEMP_4_REGISTER]; // pointer to a memory array in the Arduino

  telegram[7].u8id = BMS_ADDRESS; // slave address
  telegram[7].u8fct = 6; // function code (this one is single coil write)
  telegram[7].u16RegAdd = 5; // start address in slave
  telegram[7].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[7].au16reg = state[AUX_TEMP_5_REGISTER]; // pointer to a memory array in the Arduino

  telegram[8].u8id = BMS_ADDRESS; // slave address
  telegram[8].u8fct = 6; // function code (this one is single coil write)
  telegram[8].u16RegAdd = 6; // start address in slave
  telegram[8].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[8].au16reg = state[AUX_TEMP_6_REGISTER]; // pointer to a memory array in the Arduino    


  telegram[9].u8id = BMS_ADDRESS; // slave address
  telegram[9].u8fct = 6; // function code (this one is registers read)
  telegram[9].u16RegAdd = 7; // start address in slave
  telegram[9].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[9].au16reg = state[AUX_TEMP_7_REGISTER]; // pointer to a memory array in the Arduino
  
  // telegram 10: write a single coil
  telegram[10].u8id = BMS_ADDRESS; // slave address
  telegram[10].u8fct = 6; // function code (this one is write a single register)
  telegram[10].u16RegAdd = 8; // start address in slave
  telegram[10].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[10].au16reg =  state[AUX_TEMP_8_REGISTER]; // pointer to a memory array in the Arduino

  master.start();
  master.setTimeOut( 5000 ); // if there is no answer in 5000 ms, roll over
  u32wait = millis() + 1000;
  u8state = u8query = 0; 
  #endif
  
}



void modbusLoop()
{
  
  
  #if MODBUS_1
  switch( u8state ) {
  case 0: 
    if (millis() > u32wait) u8state++; // wait state
    break;
  case 1: 
    master.query( telegram[u8query] ); // send query (only once)
    u8state++;
    u8query++;
    if (u8query > TOTAL_NO_OF_REGISTERS) u8query = 0;
      break;
  case 2:
    //Serial.println(state[AUX_TEMP_4_REGISTER]);    
    master.poll(); // check incoming messages
    if (master.getState() == COM_IDLE) {
      u8state = 0;
      u32wait = millis() + 1000; 
    }
    break;

  state[AUX_TEMP_1_REGISTER] = (int)temp1;
  state[AUX_TEMP_2_REGISTER] = (int)temp2;
  state[AUX_TEMP_3_REGISTER] = (int)temp3;
  state[AUX_TEMP_4_REGISTER] = (int)temp4;
  state[AUX_TEMP_5_REGISTER] = (int)temp5;
  state[AUX_TEMP_6_REGISTER] = (int)temp6;
  state[AUX_TEMP_7_REGISTER] = (int)temp7;
  state[AUX_TEMP_8_REGISTER] = (int)temp8;

  }
  #endif
 
}


Hi,
Did you write your code in stages?
Getting each stage to work on its own, then combining them one at a time, getting rid of any bugs before adding the next.
If so when did this problem occur?

Do you have code that JUST sends int values onto the Modbus, forget about LEDs and sensors.
Lets see if sending int and not receiving them properly is a Modbus conversion problem, then work back.

Sorry, but you are now in debug mode and you need to strip your code back and check each part.

Tom… :grinning: :+1: :coffee: :australia:

Hey Tom,
The problem occurs when i try to send the int values of temperatures through MODBUS. Yes, i did write it in stages and all the parts of the code are working, except when i try to send the values through MODBUS. When i print the values of temp1, temp2, … temp8 on my PC monitor, i get the correct float values of them. Then when i print the values of state[AUX_TEMP_1_REGISTER] , state[AUX_TEMP_2_REGISTER], etc. i get the correct int values(in function modbusLoop).
But when i send them through MODBUS, i get random hex values or 0x00.

If it helps i am using this MODBUS RTU library MODBUS RTU library. I have followed the advanced Master example from this library and used it as a basis for my MODBUS communication

Hey Tom,
The code that just sends int values onto the MODBUS is given below

#include <ModbusRtu.h>

#if MODBUS_1 || MODBUS_2 || MODBUS_3 || MODBUS_4
#define AUX_ADDRESS 0
#define BMS_ADDRESS 0x31

#define AUX_STATE_VARIABLES_REGISTER 0x01
#define AUX_SYSTEM_STATUS_REGISTER 0x02
#define AUX_DISCHARGE_ONOFF_REGISTER 0x03
#define AUX_TEMP_1_REGISTER 0x04
#define AUX_TEMP_2_REGISTER 0x05
#define AUX_TEMP_3_REGISTER 0x06
#define AUX_TEMP_4_REGISTER 0x07
#define AUX_TEMP_5_REGISTER 0x08
#define AUX_TEMP_6_REGISTER 0x09
#define AUX_TEMP_7_REGISTER 0x0A
#define AUX_TEMP_8_REGISTER 0x0B

#define TOTAL_NO_OF_REGISTERS 11

#define RS485_TX_EN_PIN 2
#define baud 19200
#endif

#if MODBUS_1
Modbus master(AUX_ADDRESS, Serial, RS485_TX_EN_PIN);
//uint16_t modbusData[16];
//uint16_t state[TOTAL_NO_OF_REGISTERS] = {0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x6B};
uint16_t state[TOTAL_NO_OF_REGISTERS];
uint8_t u8state;
uint8_t u8query;
modbus_t telegram[TOTAL_NO_OF_REGISTERS];
unsigned long u32wait;
#endif


void modbus_setup()
{
  #if MODBUS_1 

  telegram[0].u8id = BMS_ADDRESS; // slave address
  telegram[0].u8fct = 4; // function code (this one is registers read)
  telegram[0].u16RegAdd = 10; // start address in slave
  telegram[0].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[0].au16reg = state[AUX_STATE_VARIABLES_REGISTER]; // pointer to a memory array in the Arduino

  telegram[1].u8id = BMS_ADDRESS; // slave address
  telegram[1].u8fct = 4; // function code (this one is registers read)
  telegram[1].u16RegAdd = 9; // start address in slave
  telegram[1].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[1].au16reg = state[AUX_SYSTEM_STATUS_REGISTER]; // pointer to a memory array in the Arduino

  telegram[2].u8id = BMS_ADDRESS; // slave address
  telegram[2].u8fct = 6; // function code (this one is registers read)
  telegram[2].u16RegAdd = 0; // start address in slave
  telegram[2].u16CoilsNo = 1; // number of elements (coils or registers) to read
  telegram[2].au16reg = state[AUX_DISCHARGE_ONOFF_REGISTER]; // pointer to a memory array in the Arduino

  telegram[3].u8id = BMS_ADDRESS; // slave address
  telegram[3].u8fct = 6; // function code (this one is single coil write)
  telegram[3].u16RegAdd = 1; // start address in slave
  telegram[3].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[3].au16reg = state[AUX_TEMP_1_REGISTER]; // pointer to a memory array in the Arduino

  telegram[4].u8id = BMS_ADDRESS; // slave address
  telegram[4].u8fct = 6; // function code (this one is single coil write)
  telegram[4].u16RegAdd = 2; // start address in slave
  telegram[4].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[4].au16reg = state[AUX_TEMP_2_REGISTER]; // pointer to a memory array in the Arduino  

  telegram[5].u8id = BMS_ADDRESS; // slave address
  telegram[5].u8fct = 6; // function code (this one is single coil write)
  telegram[5].u16RegAdd = 3; // start address in slave
  telegram[5].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[5].au16reg = state[AUX_TEMP_3_REGISTER]; // pointer to a memory array in the Arduino

  telegram[6].u8id = BMS_ADDRESS; // slave address
  telegram[6].u8fct = 6; // function code (this one is single coil write)
  telegram[6].u16RegAdd = 4; // start address in slave
  telegram[6].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[6].au16reg = state[AUX_TEMP_4_REGISTER]; // pointer to a memory array in the Arduino

  telegram[7].u8id = BMS_ADDRESS; // slave address
  telegram[7].u8fct = 6; // function code (this one is single coil write)
  telegram[7].u16RegAdd = 5; // start address in slave
  telegram[7].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[7].au16reg = state[AUX_TEMP_5_REGISTER]; // pointer to a memory array in the Arduino

  telegram[8].u8id = BMS_ADDRESS; // slave address
  telegram[8].u8fct = 6; // function code (this one is single coil write)
  telegram[8].u16RegAdd = 6; // start address in slave
  telegram[8].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[8].au16reg = state[AUX_TEMP_6_REGISTER]; // pointer to a memory array in the Arduino    


  telegram[9].u8id = BMS_ADDRESS; // slave address
  telegram[9].u8fct = 6; // function code (this one is registers read)
  telegram[9].u16RegAdd = 7; // start address in slave
  telegram[9].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[9].au16reg = state[AUX_TEMP_7_REGISTER]; // pointer to a memory array in the Arduino
  
  // telegram 10: write a single coil
  telegram[10].u8id = BMS_ADDRESS; // slave address
  telegram[10].u8fct = 6; // function code (this one is write a single register)
  telegram[10].u16RegAdd = 8; // start address in slave
  telegram[10].u16CoilsNo = 1; // number of elements (coils or registers) to write
  telegram[10].au16reg =  state[AUX_TEMP_8_REGISTER]; // pointer to a memory array in the Arduino

  master.start();
  master.setTimeOut( 5000 ); // if there is no answer in 5000 ms, roll over
  u32wait = millis() + 1000;
  u8state = u8query = 0; 
  #endif

}



void modbusLoop()
{

  
  #if MODBUS_1
  switch( u8state ) {
  case 0: 
    if (millis() > u32wait) u8state++; // wait state
    break;
  case 1: 
    master.query( telegram[u8query] ); // send query (only once)
    u8state++;
    u8query++;
    if (u8query > TOTAL_NO_OF_REGISTERS) u8query = 0;
      break;
  case 2:
    //Serial.println(state[AUX_TEMP_4_REGISTER]);    
    master.poll(); // check incoming messages
    if (master.getState() == COM_IDLE) {
      u8state = 0;
      u32wait = millis() + 1000; 
    }
    break;

  state[AUX_TEMP_1_REGISTER] = (int)temp1;
  state[AUX_TEMP_2_REGISTER] = (int)temp2;
  state[AUX_TEMP_3_REGISTER] = (int)temp3;
  state[AUX_TEMP_4_REGISTER] = (int)temp4;
  state[AUX_TEMP_5_REGISTER] = (int)temp5;
  state[AUX_TEMP_6_REGISTER] = (int)temp6;
  state[AUX_TEMP_7_REGISTER] = (int)temp7;
  state[AUX_TEMP_8_REGISTER] = (int)temp8;

  }
  #endif
  
}

modbus_setup() function is called in void setup() and modbusLoop() is called in the loop (void loop() ).
Please let me know the issues here.

I get the impression you don’t understand the Modbus concept. The master is the controller of the site, the sensor nodes are slaves. The master requests the sensor values. Although you can do it the other way around (so the master reads the sensors and writes the values to the slaves registers).
In your code the comments are wrong, it’s quite disturbing to read a comment and recognizing later that the code does something else but the programmer was too lazy to change the comment.

telegram[0].au16reg = state[AUX_STATE_VARIABLES_REGISTER]; // pointer to a memory array in the Arduino

If you read the comment you knew that the value must be a pointer to an integer array and not an integer.
This results in an access to a random byte which is then sent to the slave.