Irrespective of DMA Buffer size, if the USB transfer size < DMA Buffer size and a Multiple of Max Packet size (64 for full speed, 512 for high speed and 1024 for super speed), then the buffer will not be wrapped and so you wont receive data on GPIF.
So when FX3 received multiples of Max Packet size, it should be told that no more data is left to be received from USB Side.
So when sending multiples of Max Packet Size, send a ZLP (Zero length packet) after the actual data packet.
Now you will be able to receive the USB Data on the GPIF.
- Madhu Sudhan
Thank you for your help.
This problem has been solved successfully.