The initial calibration process never ends in some case, which blocks the application code to start.

[changtengfei]

The HF_CLOCK_fine code (10) here https://github.com/PisterLab/scum-test-code/blob/develop/scm_v3c/optical.c#L164 should be larger to the HF_CLOCK_FINE code (20) here https://github.com/PisterLab/scum-test-code/blob/develop/scm_v3c/optical.c#L174.

otherwise in some case, the initial calibration will be never ends. i.e. #33