Purpose of boot0 tied to PC9?

(3 posts) (2 voices)

corguy
Member

I'm not clear on the function of PC9, is it just used for isButtonPressed()? I did
not see any internal libmaple use, did i overlook something?

Also from reading past posts here I removed USB_P circuits from the VET6 board since it appears it is no longer used, is this correct?

Posted 4 years ago #
robodude666
Member

BOOT0 is pulled to ground with a pulldown resistor. When the board is reset, and BUT is pressed BOOT0 is pulled up to Vcc. This tells the Maple to go into perpetual bootloader mode so it can be re-programmed over USB. PC9 just happens to be the pin the button is connected to. Instead of having two buttons, the two pins (PC9 and BOOT0) are tied together to share the same button.

Posted 4 years ago #
corguy
Member

I noticed it was tied to boot0, I just did not see much code in libmaple but I did not look at the bootloader code. After I read your post I found the def in the bootloader config.h and it makes sense now. Thanks.

Posted 4 years ago #

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