Microsoft WDF sample driver for OSR USB-FX2 Learning Kit contains the following code:
VOID OsrFxEvtIoRead(IN WDFQUEUE Queue,
IN WDFREQUEST Request, IN size_t Length)
{
if ( Length > TEST_BOARD_TRANSFER_BUFFER_SIZE )
{
// report error
}
…
TEST_BOARD_TRANSFER_BUFFER_SIZE is defined as 64*1024. I try to find confirmation of this in the Learning Kit description OSRFX2_32.pdf. For example, there is the following text:
When operating in full speed, the maximum packet size is 64 bytes. When operating in high speed, the maximum packet size is 512 bytes.
My question is: why is TEST_BOARD_TRANSFER_BUFFER_SIZE constant defined as 64*1024?
Thanks.
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