Hi,
I had the same issue with mpu_init returning -7 using MPU6500.
As you mentioned that the chip_cfg.sensors is correct to be 0 at this stage, but in mpu_read_mem it will directly return -1 before chip_cfg.sensors is set.
I tried to delete ArduinoMotionSensorExample/inv_mpu.cpp at master · rpicopter/ArduinoMotionSensorExample · GitHub, but it still return READ ERROR with error code -1.
I am new with Arduino and motion sensors. Thanks for your help!
CWhy