OTG device IN endpoint 0 transfer size register
XFRSIZ | Transfer size Indicates the transfer size in bytes for endpoint 0. The core interrupts the application only after it has exhausted the transfer size amount of data. The transfer size can be set to the maximum packet size of the endpoint, to be interrupted at the end of each packet. The core decrements this field every time a packet from the external memory is written to the Tx FIFO. |
PKTCNT | Packet count Indicates the total number of USB packets that constitute the transfer size amount of data for endpoint 0. This field is decremented every time a packet (maximum size or short packet) is read from the Tx FIFO. |