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DAC, SPI, USART and flashing

Question asked by a. richard on Sep 27, 2010
Latest reply on Sep 29, 2010 by MaxPower
Hello. I'm trying to make a simple experiment with the discovery board - read data from an SD card and output it to the DACs. I've set up the DACs with the examples from UM0427 and they work right, and i've changed the default pinout for SPI - because the default one uses the DAC pins. Unfortunately, the alternative pinout uses the JTAG pins, and after I disabled JTAG in software and ran the app, I realized maybe I shouldn't have done that - can't flash the board anymore, because the SPI clock outputs on the JTAG data lines too fast after reset.

So I've unsoldered JM16 on the board, which makes BOOT0 to be pulled-up at 3v3, ran the AN3155 USART bootloader and erased the old software. Now I can use ST-Link flashing/debugging again.

Any smart hacks I could try to use hardware SPI and STLINK? I think flashing via USART is the only available option.

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