ModBusESP32TacoChickenSHT20

#include <ModbusMaster.h>

#define MAX485_RE_DE  5

ModbusMaster node;

void preTransmission() {
  digitalWrite(MAX485_RE_DE, 1);
}

void postTransmission() {
  digitalWrite(MAX485_RE_DE, 0);
}

void setup() {
  // Initialize control pins
  pinMode(MAX485_RE_DE, OUTPUT);
  digitalWrite(MAX485_RE_DE, 0);

  // Modbus communication runs at 9600 baud
  Serial.begin(115200);
  Serial1.begin(9600, SERIAL_8N1, 2, 15);

  // 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() {
  // Request 2 registers starting at 0x0001
  uint8_t result = node.readInputRegisters(0x0001, 2);
  Serial.println("Data Requested");

  if (result == node.ku8MBSuccess) {
    // Get response data from sensor
    Serial.print("Temperature: ");
    Serial.print(float(node.getResponseBuffer(0) / 10.00F));
    Serial.print("   Humidity: ");
    Serial.println(float(node.getResponseBuffer(1) / 10.00F));
  }
  delay(1000);
}