#include <SoftwareSerial.h>



#define SSerialRX        9
#define SSerialTX        8
#define SSerialTxControl 7
#define RS485Transmit    HIGH
#define RS485Receive     LOW

SoftwareSerial RS485Serial(SSerialRX, SSerialTX); // RX, TX

#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);


struct mydata {
  int cmd[3];
  int count[3];
  int temp[3];
  char str[20];
  float val[2] ;
};
mydata dato;

byte stato = 0;
unsigned long previousMillis  = 0;
const long interval           = 500;

byte buff[100];
int i = 0;

void setup() {
  lcd.begin();
  lcd.backlight();
  RS485Serial.begin(9600);
  Serial.begin(9600);
  pinMode(SSerialTxControl, OUTPUT);
  digitalWrite(SSerialTxControl, RS485Receive);
}



void loop() {
  if (millis() - previousMillis >= interval) {
    previousMillis += interval;
    digitalWrite(SSerialTxControl, RS485Transmit);
    RS485Serial.write(stato );  //produce una sequenza: 0, 1, 2
    digitalWrite(SSerialTxControl, RS485Receive);  // Disable RS485 Transmit
    if (stato < 5) stato = stato + 1;
    else  stato = 0;
  }

  if (stato == 0) {
    if (RS485Serial.available()) {
      lcd.clear();
      byte n = RS485Serial.read();
      if ((char)n == '\n') {
        memcpy(&dato, buff, i);
        Serial.print(stato);        Serial.println(" stato");
        Serial.print(dato.cmd[1]);  Serial.print(" - ");
        Serial.print(dato.count[1]); Serial.print(" - ");
        Serial.print(dato.val[1]);  Serial.print(" - ");
        Serial.print(dato.temp[1]); Serial.print("\n");
        Serial.print(dato.str);     Serial.print("\n");
        Serial.print("ricevuti: "); Serial.println("bytes END");

        lcd.setCursor(0, 0);        lcd.print(dato.cmd[1]);
        lcd.setCursor(6, 0);        lcd.print(dato.val[1], 2);
        lcd.setCursor(0, 1);        lcd.print(dato.count[1]);
        lcd.setCursor(0, 2);        lcd.print(dato.temp[1]);
        lcd.setCursor(6, 1);        lcd.print(dato.val[0]);
        lcd.setCursor(0, 3);        lcd.print(dato.str);
        lcd.setCursor(12, 0);       lcd.print("ricevuti");
        lcd.setCursor(12, 1);       lcd.print(i);
        lcd.setCursor(15, 1);       lcd.print("byte");
        i = 0;
      } else {
        buff[i] = n;
        i++;
      }
    }
  }
}