[usb] Handshake to OUT transaction

[Ilja_Alekssev@mail.ru]

i can't understud this phenomen:

my configuration of EndPoint:
EP1 -IN Bulk MaxPacket size - 64
size of EP1 FIFO 256 byte
EP2 -OUT Bulk MaxPacket size - 64
size of EP2 FIFO 256 byte

when i write OUT in EP2 3 packet with PID sequence DATA0-1-0 core say
me with
ACK handshake. and all 3 packet (total 64*3 bytes) fit in EP2 FIFO
correctly.
after that in EP2 FIFO is 64 bytes free space.
and when i write OUT to EP2 packet with PID DATA1 (size of packet: 64
byte) core
say me NAK! But all last 64 byte (from last packet) in EP2 FIFO fit
correctly.
in write-time(EP2_WE is Hi) of last byte in Last packet EP2_Full is
Rise__/---

If i make 3 time write 64 bytes and 1 time 63 byte, core say me 4 time
ACK and
64*3+63 bytes fit in EP2 FIFO.

resume:
256 byte sucessfuly writed to EP2 FIFO but USB core say me NAK to last
transaction !  is this right?
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