On Wed, Jul 13, 2011 at 4:23 AM, Spencer Oliver <[email protected]> wrote: > On 12/07/2011 20:56, Peter Stuge wrote: >> >> Spencer Oliver wrote: >>>> >>>> Why are we duplicating effort on two different libraries that >>>> accomplish exactly the same thing? >>> >>> Main reason is that ftd2xx works better/faster on windoze. >> >> Is it known how much, and why? >> > > off the top of my head no - the list archive has quite a few threads on this > subject. > > Xiaofan will probably be able to help here.
I have not done benchmark comparison recently. However, Freddie and Laurent have done some benchmarks last time and ftd2xx is significantly faster. https://lists.berlios.de/pipermail/openocd-development/2009-June/008193.html I will try to do some benchmarks over the weekend. I can think of several reasons why using ftd2xx is faster and "better" for Windows users. I like libftdi and libusb myself. :-) 1) OpenOCD still uses libftdi-0.1x and does not use the async capability of libftdi-1.0. libftdi-1.0 has not been officially released. libusb-1.0 Windows too has not been officially released (1.0.9 release is not yet there). (ft2232.c) 382 #if BUILD_FT2232_FTD2XX == 1 383 #define FT2232_BUFFER_READ_QUEUE_SIZE (64*64) 384 #else 385 #define FT2232_BUFFER_READ_QUEUE_SIZE (64*4) 386 #endif The above codes also favor ftd2xx. 2) To use libftdi, the user has to use libusb-win32 driver. With the release of libusb-win32 1.2.x and the GUI Filter Driver Wizard, this becomes less an issue now but still it is one step for the user. -- Xiaofan _______________________________________________ Openocd-development mailing list [email protected] https://lists.berlios.de/mailman/listinfo/openocd-development
