WiPy -> AM2315 env sensor - I2C interface

[Kevin Hanna]

Has anyone successfully interfaced to the AM2315 temp / humidity sensor?
If so what modules did you use?

Thanks
kevin Hanna

[livius]

this is really simple sensor I2C
you can change code to python

oolean Adafruit_AM2315::readData(void) {
  uint8_t reply[10];
  
  // Wake up the sensor
  Wire.beginTransmission(AM2315_I2CADDR);
  delay(2);
  Wire.endTransmission();

  // OK lets ready!
  Wire.beginTransmission(AM2315_I2CADDR);
  Wire.write(AM2315_READREG);
  Wire.write(0x00);  // start at address 0x0
  Wire.write(4);  // request 4 bytes data
  Wire.endTransmission();
  
  delay(10); // add delay between request and actual read!

  Wire.requestFrom(AM2315_I2CADDR, 8);
  for (uint8_t i=0; i<8; i++) {
    reply[i] = Wire.read();
    //Serial.println(reply[i], HEX);
  }
  
  if (reply[0] != AM2315_READREG) return false;
  if (reply[1] != 4) return false; // bytes req'd
  
  humidity = reply[2];
  humidity *= 256;
  humidity += reply[3];
  humidity /= 10;
  //Serial.print("H"); Serial.println(humidity);

  temp = reply[4] & 0x7F;
  temp *= 256;
  temp += reply[5];
  temp /= 10;
  //Serial.print("T"); Serial.println(temp);

  // change sign
  if (reply[4] >> 7) temp = -temp;

  return true;
}


float Adafruit_AM2315::readTemperature(void) {
  if (! readData()) return NAN;
  return temp;
}

float Adafruit_AM2315::readHumidity(void) {
  if (! readData()) return NAN;
  return humidity;
}