USIE_UC_RX
usbd_transfer_start(sc->sc_uc_xfer[USIE_HIP_IF][USIE_UC_RX]);
[USIE_UC_RX] = {
usbd_transfer_start(sc->sc_uc_xfer[ucom->sc_subunit][USIE_UC_RX]);
usbd_transfer_stop(sc->sc_uc_xfer[ucom->sc_subunit][USIE_UC_RX]);