就是在一直找这个标志位哈,测试了OTG_HS_DIEPINT1寄存器的ITTXFE(Bit 4 ITTXFE: IN token received when TxFIFO is empty
Applies to non-periodic IN endpoints only.
Indicates that an IN token was received when the associated TxFIFO (periodic/non-periodic)
was empty. This interrupt is asserted on the endpoint for which the IN token was received.). 就是在每一次发送前确保这个ITTXFE置1,用BUS HOUND仍然丢包严重。