UBSER_BULK_DT_RD
[UBSER_BULK_DT_RD] = {
usbd_xfer_set_stall(sc->sc_xfer[UBSER_BULK_DT_RD]);
usbd_transfer_start(sc->sc_xfer[UBSER_BULK_DT_RD]);
usbd_transfer_start(sc->sc_xfer[UBSER_BULK_DT_RD]);
usbd_transfer_stop(sc->sc_xfer[UBSER_BULK_DT_RD]);