Arduino/ESP32 查找IIC设备的地址

凌顺实验室（lingshunlab.com）在使用IIC的时候，经常需要检查IIC设备是否通信正常，或者有些修改了IIC地址的设备。

凡I2C连接的都可以使用这样的代码，找到设备的I2C地址。

代码试用于Arduino 和 ESP32（Arduino框架）

效果

把模块按接线接好，上传这段代码后，打开端口监视器，就能找到在I2C上的设备地址

接线

根据模块的I2C接线就可以了

程序代码

// welcome to lingshunlab.com
// 详细说明：https://lingshunlab.com/book/arduino/arduino-esp32-scan-iic-device-address
#include <Wire.h>

void setup(){
  Wire.begin();
  Serial.begin(115200);
  Serial.println("\nI2C Scanner");
}
void loop(){
  byte error, address;
  int nDevices;
  Serial.println("Scanning...");
  nDevices = 0;
  for (address = 1; address < 127; address++ ){
    // The i2c_scanner uses the return value of
    // the Write.endTransmisstion to see if
    // a device did acknowledge to the address.
    Wire.beginTransmission(address);
    error = Wire.endTransmission();
    if (error == 0){
      Serial.print("I2C device found at address 0x");
      if (address < 16)
        Serial.print("0");
      Serial.print(address, HEX);
      Serial.println(" !");
      nDevices++;
    }else if (error == 4){
      Serial.print("Unknow error at address 0x");
      if (address < 16)
        Serial.print("0");
      Serial.println(address, HEX);
    }
  }
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("done\n");
  delay(5000); // wait 5 seconds for next scan
}