esp32 arduino rgb

为了控制RGB LED，我们需要将其连接到ESP32开发板上。RGB LED有四个引脚，其中一个是共阳极，其余三个是红色，绿色和蓝色引脚。我们将共阳极连接到ESP32的3.3V引脚，而红色，绿色和蓝色引脚将连接到ESP32的GPIO 12，GPIO 13和GPIO 14引脚。

以下是ESP32 Arduino控制RGB LED的示例代码：

#include <WiFi.h>
#include <PubSubClient.h>

const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";
const char* mqtt_server = "your_MQTT_BROKER_IP";

WiFiClient espClient;
PubSubClient client(espClient);

int redPin = 12;
int greenPin = 13;
int bluePin = 14;

void setup() {
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);

  Serial.begin(115200);
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }

  Serial.println("Connected to WiFi");

  client.setServer(mqtt_server, 1883);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
}

void reconnect() {
  while (!client.connected()) {
    Serial.println("Connecting to MQTT Broker...");
    if (client.connect("ESP32Client")) {
      Serial.println("Connected to MQTT Broker");
      client.subscribe("rgb");
    } else {
      Serial.print("Failed to connect to MQTT Broker, rc=");
      Serial.print(client.state());
      Serial.println(" retrying in 5 seconds");
      delay(5000);
    }
  }
}

void callback(char* topic, byte* payload, unsigned int length) {
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
  }
  Serial.println();

  String message = String((char*)payload);

  if (message == "red") {
    digitalWrite(redPin, HIGH);
    digitalWrite(greenPin, LOW);
    digitalWrite(bluePin, LOW);
  } else if (message == "green") {
    digitalWrite(redPin, LOW);
    digitalWrite(greenPin, HIGH);
    digitalWrite(bluePin, LOW);
  } else if (message == "blue") {
    digitalWrite(redPin, LOW);
    digitalWrite(greenPin, LOW);
    digitalWrite(bluePin, HIGH);
  } else if (message == "off") {
    digitalWrite(redPin, LOW);
    digitalWrite(greenPin, LOW);
    digitalWrite(bluePin, LOW);
  }
}

在此示例中，我们使用MQTT协议控制RGB LED。我们将RGB LED连接到ESP32的引脚12,13和14上，并将其连接到MQTT代理。我们可以通过向“rgb”主题发布消息来控制RGB LED的颜色。如果消息是“red”，则将点亮红色LED，如果消息是“green”，则将点亮绿色LED，如果消息是“blue”，则将点亮蓝色LED，如果消息是“off”，则将关闭所有LED。