XUSB_EP_BUF1COUNT_OFFSET
udc->write_fn(udc->addr, ep->offset + XUSB_EP_BUF1COUNT_OFFSET,
XUSB_EP_BUF1COUNT_OFFSET, length);
XUSB_EP_BUF1COUNT_OFFSET, bufferlen);
bufoffset = XUSB_EP_BUF1COUNT_OFFSET;