Force imu 6050 to start yaw =0 in a physical plane position after calibration process  #731

Hello all, I am building a tilt compensate compass with LSM303DLHC and imu 6050 .

All is good during the calibration process I have manage to store the offset before the interrupt and my compass is working well with dmp sketch.

my problem after the calibration on a flat surface is that i want that yaw start at 0 on a physical position of the couple LSM303DLHC and imu 6050 .

I am lost is it possible to achieve this .