pThe GY-271 Compass Module used the HMC5883L chip .It is the 3 axis magnetic electronic compass designed for low field magnetic sensing usually used for small projects./p
pGY-45 MMA845x Sensor, digital triaxial modules is embedded functions with flexible user-programmable option. Its mostly used for Static orientation detection, E-compass application and many more. It has 14-bit and 8-bit digital output with user selectable dynamic range of ±2g/±4g/±8g. It easy to use . It has features of vibration detection and pulse detection./p