IMU AHRS module firmware Firmware for module from yoochip (alibaba.com). Store url: http://www.aliexpress.com/store/product/IMU-AHRS-10DOF-sensor-module-MPU-6050-HMC5883L-BPM085-STM32F103T8-3-axis-gyroscope-and-3-axis/712248_602760725.html Note: minimum calculations on the module, just raw sensor data. Simple binary serial protocol: START, MSGID, TIME, LEN, PAYLOAD, CRC8