Galactech Teensy 4.0 Light Sensor

GalactechSensor.ino

#include <Wire.h>

void setup() {
  // put your setup code here, to run once:
  pinMode(0, OUTPUT);
  Wire.begin();
  Serial.begin(115200);
  Wire.beginTransmission(0x52);

  // MAIN_CTRL (only turn on proximity sensor)
  Wire.send(0x00);
  Wire.send(0b00000111);

  // PS_MEAS_RATE (11-bit precision, measures every 12.5 milliseconds);
  Wire.send(0x03);
  Wire.send(0b00011010);

  Wire.endTransmission();
}

byte first, second;
bool overflow;
int proximity;
int error;

void loop() {
  Wire.beginTransmission(0x52);
  // Ask for PS_DATA
  Wire.write(0x08);
  int error = Wire.endTransmission();
  if (error != 0) {
    Serial.print("ERROR!!! ");
    Serial.println(error);
  } else {
    Serial.println("OK");
  }

  Wire.requestFrom(0x52, 2);
  first  = Wire.read();
  second = Wire.read();

  overflow  = (second >> 3) == 1;
  proximity = (int)(second & 0b111) << 8;
  proximity = proximity | first;

  Serial.println(proximity);
  digitalWrite(0, (proximity > 15) ? HIGH : LOW);

  delay(20);
}