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ARMmbed / DAPLink

https://daplink.io
Apache License 2.0
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DAPLink Download Speed #627

Open Fairchi1d opened 5 years ago

Fairchi1d commented 5 years ago

Compared with the ulink2 debugger, the download speed of daplink is much slower. Following list for details. SWD mode 10MHz File Size 40KB: DAPLink 5.1s ULINK2 4.3s File Size 113KB: DAPLink 13.2s ULINK2 11s File Size 241KB: DAPLink 27s ULINK2 22s

Is there a way to increase the speed?thank!

flit commented 5 years ago

Well, that's not really "much" slower… Due to the purely software based transfers, the SWD/JTAG frequency maxes out at ~1.7-2.3 MHz (it's also nonlinear), depending on the HIC. DAPLink uses the reference CMSIS-DAP code unmodified (like most CMSIS-DAP probes).

The frequency can be improved, but only by taking advantage of HIC-specific hardware and doing something like timer-driven DMA transfers to GPIO. However, flash programming is primarily bound by the performance of the target's flash controller rather than SWD/JTAG clock (as long as the host debugger is smart and does things like double buffering). Given that, plus the large number of HICs supported by DAPLink, this has never been a priority.