SKU: OT5003 Numero articolo: AA119 EAN: 8720618231512
Modulo MAX485 con chip MAX485 a basso consumo per comunicazione RS-485. RS485 viene utilizzato per la comunicazione seriale su distanze maggiori rispetto a RS232 o TTL diretti e supporta più unità sullo stesso bus.
Specifiche del modulo MAX485:
– Funziona a: 5V.
– Connessione onboard per i cavi RS-485.
– Dimensioni: 44mm x 14mm.
Dimensioni
Lunghezza: 4,39cm
Larghezza: 1,41cm
Altezza: 1,89cm
Ecco come collegare il Modulo convertitore MAX485 TTL a RS485 a un Arduino UNO o ESP32, con uno sketch di esempio che puoi caricare subito.
Questo circuito collega un Arduino Uno a un bus differenziale RS-485 tramite il transceiver MAX485. SoftwareSerial gestisce la comunicazione con il modulo, mentre i pin digitali controllano le modalità di trasmissione e ricezione. Qualsiasi messaggio digitato nel Serial Monitor viene trasmesso su RS-485, e i dati in arrivo dal bus vengono visualizzati sullo schermo.
/*
* ==================================================================
* 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
Questo progetto mostra come inviare e ricevere dati su un bus RS-485 utilizzando il modulo MAX485 e UART2 dell'ESP32. L'ESP32 porta i pin DE/RE HIGH per trasmettere un messaggio heartbeat periodico e li porta LOW per ascoltare i pacchetti RS-485 in arrivo. Un semplice partitore di tensione 1kΩ/2kΩ abbassa in անվտանգe la uscita TTL 5V (RO) del modulo a 3.3V per il pin RX dell'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