USB2_TX_REG0
u2o_clear(base, USB2_TX_REG0, USB2_TX_IMPCAL_VTH_MASK_MMP3);
u2o_set(base, USB2_TX_REG0, 2 << USB2_TX_IMPCAL_VTH_SHIFT_MMP3);
u2o_set(base, USB2_TX_REG0, 1 << USB2_TX_RCAL_START_SHIFT_MMP3);
u2o_clear(base, USB2_TX_REG0, 1 << USB2_TX_RCAL_START_SHIFT_MMP3);