Programming Info D2XXPG31.pdf

71 D2XX Programmer's Guide4.5 FT_SetUSBParametersSet the USB request transfer size.FT_STATUS FT_SetUSBParameters (FT_HANDLE ftHandle, DWORD dwInTransferSize,DWORD dwOutTransferSize)ParametersftHandledwInTransferSizedwOutTransferSizeHandle of the device.Transfer size for USB IN request.Transfer size for USB OUT request.Return ValueFT_OK if successful, otherwise the return value is an FT error code.RemarksPreviously, USB request transfer sizes have been set at 4096 bytes and have not beenconfigurable. This function can be used to change the transfer sizes to better suit the applicationrequirements.Note that, at present, only dwInTransferSize is supported.ExampleHANDLE ftHandle;FT_STATUS ftStatus;DWORD InTransferSize = 16384;ftStatus = FT_Open(0, &ftHandle);if(ftStatus != FT_OK) {// FT_Open failedreturn;}ftStatus = FT_SetUSBParameters(ftHandle, InTransferSize, 0);if (ftStatus == FT_OK) {// In transfer size set to 16 Kbytes}else {// FT_SetUSBParameters FAILED!}FT_Close(ftHandle);© Future Technology Devices International Ltd. 2005