Application background HID transmission is too slow. I am doing experiments need more than 2m data transmission, and is the flow of data, real-time data, so I want to try the BOT, tangled for many days, you said USB USB_Istr () inside the operation is not only some flags, to be honest this code is not read & nbsp; T^T or to send and receive buffer, did not see tracking simulation, online to see if the F105 or F107 can use OTG, but battleship board is F103... I myself used the double pipeline. Key Technology   USB; debugging, you can directly simulate the function of U disk, support FLASH and SD card two models. Read and write speed is also used to double pipe mechanism, more suitable for transplantation, support the Chinese FATFS and long file name!