MDP4_VG_PHASE_STEP_DEFAULT
uint32_t phasex_step = MDP4_VG_PHASE_STEP_DEFAULT;
uint32_t phasey_step = MDP4_VG_PHASE_STEP_DEFAULT;
phasex_step = mult_frac(MDP4_VG_PHASE_STEP_DEFAULT,
phasey_step = mult_frac(MDP4_VG_PHASE_STEP_DEFAULT,