On Sat, Jul 16, 2011 at 10:55 AM, Xiaofan Chen <[email protected]> wrote: > On Sat, Jul 16, 2011 at 10:31 AM, Xiaofan Chen <[email protected]> wrote: > >> Actually the result is pretty close for the LPC-P2148 based test. >> jtag_khz = 1500 KHz, 38.927 KiB/s (ftd2xx) versus 38.754 KiB/s. >> > > The above is for Amontec JtagKey2 which is high speed USB. > > The J-Link under OpenOCD (full speed USB but with intelligence > in it) seems much slower than Amontec JtagKey2. The speed > is 18.813 KiB/s at the same 1500KHz jtag_khz for J-Link (V6, IAR OEM). >
On the other hand, J-Link can be much faster when not using OpenOCD but Segger's own gdb server. So OpenOCD has a long way to go to match that one. Reference: http://www.yagarto.de/projects/jtagspeed/index.html Other historical reference, it seems OpenOCD is getting faster and faster with each release. So it is good. http://comments.gmane.org/gmane.comp.debugging.openocd.devel/7425 Overall, I think Øyvind Harboe's thoughts are good. https://lists.berlios.de/pipermail/openocd-development/2010-October/016724.html "Somebody just has to step up and do the work to profile the Cortex-M3 flash programming case and rewrite the higher level codes and performance should be dramatically improved. >From a maintenance point of view, I believe it would be *MUCH* more economical to simply fix the higher level OpenOCD code to be more robust towards longer latencies. That code can be tested on *all* interfaces. If OpenOCD can get maintainable code that runs at > 50% maximum theoretical throughput, then I think we should be very pleased. More performance is better, but at 50% throughput, I wouldn't trade much for reduced maintainability." -- Xiaofan _______________________________________________ Openocd-development mailing list [email protected] https://lists.berlios.de/mailman/listinfo/openocd-development
