TempAndHumidity(SCRAPPED)

//temperature and humidity sensing code using arduino
//SCRAPPED IN FINAL PROJECT

//wiring: 3.3V, GND, SDA, SCL

#include <Wire.h>

#define AHT20_ADDR 0x38

void setup() {
  Serial.begin(9600);
  while (!Serial);
  Wire.begin();
  Wire.setClock(100000);
  delay(100);

  Wire.beginTransmission(AHT20_ADDR);
  Wire.write(0xBA);
  Wire.endTransmission();
  delay(20);

  //reading status to see if i2c communication happening 
  Wire.requestFrom(AHT20_ADDR, 1);
  uint8_t status = Wire.available() ? Wire.read() : 0xFF;
  Serial.print("Status: 0x"); Serial.println(status, HEX);

  //re-initalize if i2c comms not working
  //fix for issues with i2c communication on first loop iteration
  if (!(status & 0x08)) {
    Serial.println("Sending init...");
    Wire.beginTransmission(AHT20_ADDR);
    Wire.write(0xBE);
    Wire.write(0x08);
    Wire.write(0x00);
    Wire.endTransmission();
    delay(10);
  }
}

void loop() {
  //measuring trigger to debug
  //was not working b/c previous sensor fried
  Wire.beginTransmission(AHT20_ADDR);
  Wire.write(0xAC);
  Wire.write(0x33);
  Wire.write(0x00);
  Wire.endTransmission();

  delay(100);

  //read first seven bytes (temp and humidity data)
  uint8_t bytes = Wire.requestFrom(AHT20_ADDR, 7);

  if (bytes < 6) {
    Serial.print("ERROR: only got "); Serial.print(bytes); Serial.println(" bytes");
    delay(2000);
    return;
  }

  uint8_t data[7] = {0};
  for (int i = 0; i < bytes; i++) {
    data[i] = Wire.read();
  }

  //print raw bytes
  //was having issue with bytes only being zeros, used for debugging
  Serial.print("Raw: ");
  for (int i = 0; i < bytes; i++) {
    if (data[i] < 0x10) Serial.print("0");
    Serial.print(data[i], HEX); Serial.print(" ");
  }
  Serial.println();

  //checking status byte to see if trigger occurred
  uint8_t statusByte = data[0];
  if (statusByte & 0x80) {
    Serial.println("Sensor still busy, skipping.");
    delay(2000);
    return;
  }

  //parsing data based on data sheet of sensor
  uint32_t rawHum  = ((uint32_t)data[1] << 12)
                   | ((uint32_t)data[2] << 4)
                   | (data[3] >> 4);
  uint32_t rawTemp = ((uint32_t)(data[3] & 0x0F) << 16)
                   | ((uint32_t)data[4] << 8)
                   |  data[5];

  Serial.print("rawHum="); Serial.print(rawHum);
  Serial.print("  rawTemp="); Serial.println(rawTemp);

  //equations found in data sheet
  float humidity = (rawHum  / 1048576.0f) * 100.0f;
  float tempC    = (rawTemp / 1048576.0f) * 200.0f - 50.0f;
  float tempF    = tempC * 9.0f / 5.0f + 32.0f;

  Serial.print("Temperature: "); Serial.print(tempC, 1);
  Serial.print(" C  /  ");      Serial.print(tempF, 1); Serial.println(" F");
  Serial.print("Humidity:    "); Serial.print(humidity, 1); Serial.println(" %RH");
  delay(2000);
}