SKU: OT5003 Número de artículo: AA119 EAN: 8720618231512
Módulo MAX485 con el chip MAX485 de bajo consumo para comunicación RS-485. RS485 se utiliza para comunicación serie a distancias mayores que RS232 o TTL directos y admite varias unidades en el mismo bus.
Especificaciones del módulo MAX485:
– Funciona a: 5V.
– Conexión onboard para cables RS-485.
– Medidas: 44mm x 14mm.
Dimensiones
Longitud: 4,39cm
Anchura: 1,41cm
Altura: 1,89cm
Así conectas el Módulo convertidor MAX485 TTL a RS485 a un Arduino UNO o ESP32, con un sketch de ejemplo que puedes subir directamente.
Este circuito conecta un Arduino Uno con un bus diferencial RS-485 mediante el transceptor MAX485. SoftwareSerial gestiona la comunicación con el módulo, mientras que los pines digitales controlan los modos de transmisión y recepción. Cualquier mensaje escrito en el Serial Monitor se transmite por RS-485, y los datos entrantes del bus se muestran en la pantalla.
/*
* ==================================================================
* Generated by Codey.online — https://www.codey.online
* ==================================================================
* Project : MAX485 RS-485 Transceiver Communication
* Board : Arduino UNO (arduino:avr:uno)
* Parts : MAX485 TTL to RS485 Converter Module
* Libraries : none (built-in)
*
* Codey Online is an AI-powered browser IDE for Arduino and ESP32.
* Describe your project and Codey writes the code, draws the wiring
* diagram and uploads it to your board, straight from the browser.
* This code is free to use, modify and share, without warranty.
* ==================================================================
*/
#include <SoftwareSerial.h>
const byte PIN_RO = 2; // Receiver Out (RX)
const byte PIN_DI = 3; // Driver In (TX)
const byte PIN_DE = 4; // Driver Enable (Active HIGH)
const byte PIN_RE = 5; // Receiver Enable (Active LOW)
SoftwareSerial rs485(PIN_RO, PIN_DI);
unsigned long lastSend = 0;
int packetCount = 0;
void setTransmitMode() {
digitalWrite(PIN_RE, HIGH); // Disable receiver
digitalWrite(PIN_DE, HIGH); // Enable driver
delayMicroseconds(50);
}
void setReceiveMode() {
digitalWrite(PIN_DE, LOW); // Disable driver
digitalWrite(PIN_RE, LOW); // Enable receiver
delayMicroseconds(50);
}
void rs485Send(const String &msg) {
setTransmitMode();
rs485.println(msg);
rs485.flush();
setReceiveMode();
}
void setup() {
pinMode(PIN_DE, OUTPUT);
pinMode(PIN_RE, OUTPUT);
setReceiveMode();
Serial.begin(115200);
rs485.begin(9600);
Serial.println(F("MAX485 RS-485 Transceiver Demo"));
Serial.println(F("Type a message and press Enter to send over RS-485."));
}
void loop() {
// Forward incoming Serial Monitor input to RS-485
if (Serial.available()) {
String input = Serial.readStringUntil('\n');
input.trim();
if (input.length() > 0) {
Serial.print(F("Sending: "));
Serial.println(input);
rs485Send(input);
}
}
// Forward received RS-485 data to Serial Monitor
if (rs485.available()) {
Serial.print(F("Received: "));
while (rs485.available()) {
char c = (char)rs485.read();
Serial.print(c);
delay(2);
}
Serial.println();
}
// Automatically send a heartbeat packet every 5 seconds
if (millis() - lastSend >= 5000) {
lastSend = millis();
packetCount++;
String packet = "Ping #" + String(packetCount);
Serial.print(F("Auto-transmitting: "));
Serial.println(packet);
rs485Send(packet);
}
}
Wiring diagram and example code generated by Codey.online — https://www.codey.online
Este proyecto demuestra cómo enviar y recibir datos a través de un bus RS-485 usando el módulo MAX485 y UART2 del ESP32. El ESP32 pone los pines DE/RE en HIGH para transmitir un mensaje heartbeat periódico y los pone en LOW para escuchar los paquetes RS-485 entrantes. Un simple divisor de tensión de 1kΩ/2kΩ reduce de forma segura la salida TTL de 5V (RO) del módulo a 3.3V para el pin RX del ESP32.
/*
* ==================================================================
* Generated by Codey.online — https://www.codey.online
* ==================================================================
* Project : MAX485 RS-485 Communication with ESP32
* Board : ESP32 DEVKIT V1 (esp32:esp32:esp32doit-devkit-v1)
* Parts : MAX485 TTL to RS485 Converter Module
* Libraries : none (built-in)
*
* Codey Online is an AI-powered browser IDE for Arduino and ESP32.
* Describe your project and Codey writes the code, draws the wiring
* diagram and uploads it to your board, straight from the browser.
* This code is free to use, modify and share, without warranty.
* ==================================================================
*/
// MAX485 TTL to RS-485 transceiver demo with ESP32
const int CONTROL_PIN = 4; // Controls DE and RE (HIGH = Transmit, LOW = Receive)
const int RXD2_PIN = 16;
const int TXD2_PIN = 17;
unsigned long lastSendTime = 0;
int messageCount = 0;
void setup() {
Serial.begin(115200);
pinMode(CONTROL_PIN, OUTPUT);
digitalWrite(CONTROL_PIN, LOW); // Start in receive mode
// Initialize UART2 for RS-485 communication
Serial2.begin(9600, SERIAL_8N1, RXD2_PIN, TXD2_PIN);
Serial.println("RS-485 Transceiver Ready");
}
void loop() {
// Send a message every 2 seconds
if (millis() - lastSendTime >= 2000) {
lastSendTime = millis();
messageCount++;
// Enable RS-485 transmitter
digitalWrite(CONTROL_PIN, HIGH);
delay(10);
String msg = "Hello from ESP32 #" + String(messageCount);
Serial2.println(msg);
Serial2.flush(); // Wait until all outgoing bytes are transmitted
// Return to receive mode
digitalWrite(CONTROL_PIN, LOW);
Serial.print("Sent over RS-485: ");
Serial.println(msg);
}
// Check for incoming RS-485 data
if (Serial2.available()) {
Serial.print("Received via RS-485: ");
while (Serial2.available()) {
char c = (char)Serial2.read();
Serial.print(c);
}
Serial.println();
}
}
Wiring diagram and example code generated by Codey.online — https://www.codey.online