[ESP32 xBee EVM] Arduino I2C 테스트 - PCF8574, 거리 측정 센서 VL53L01

[ESP32 xBee EVM] 보드의 I2C는 IO22(SCL), IO22(SDA) 에 할당되어 있다.

 

 

ESP32 I2C
SDA (default : GPIO 21)
SCL (default : GPIO 22)

 

I2C GPIO 확장 PCF8574 SSM 모듈 보드와  거리 측정 센서 VL53L01 모듈을 이용하여 거리값에 따라 LED 거리정보를 측정해 보자

 

#include <Wire.h>
#include <VL53L0X.h>

#define PIN_LED1            13
#define PCF_8574_ADDR      0x20
void write8(uint8_t Address, uint8_t Value)
{
   Wire.beginTransmission(Address);
   Wire.write(Value);
   Wire.endTransmission();
}

uint8_t read8(uint8_t Address, uint8_t Value)
{
   uint8_t ret;
    
   Wire.beginTransmission(Address);
   Wire.write(Value);
   Wire.endTransmission();
   Wire.requestFrom(Address, (uint8_t)1);
   ret = Wire.read();
   return ret;   
}


VL53L0X sensor;

void setup()
{
  Serial.begin(115200);

  Serial.println("initialize sensor!");
  Wire.begin();
  
  pinMode(PIN_LED1, OUTPUT); digitalWrite(PIN_LED1, 0);

  sensor.setTimeout(500);
  write8(PCF_8574_ADDR, 0xf0);

  Serial.println(read8(PCF_8574_ADDR, 0));
  Serial.println("start");
  if (!sensor.init(1))
  {
    Serial.println("Failed to detect and initialize sensor!");
    while (1) {}
  }

  sensor.startContinuous();
}

int cnt = 0;
void loop()
{
  int disp[] = {1,3,7,0xf,0x51f,0x3f,0x7f,0xff};
  int i;
  
  delay(100);

  cnt = sensor.readRangeContinuousMillimeters();
  if(cnt>2000)
  {
     cnt = 2000;
  }
    
  Serial.println(cnt);

  i = cnt/64;
  //Serial.println(i);
  if(i>7)i=7;

  write8(PCF_8574_ADDR, ~(disp[i] ));
}