Enable nRST pullup (Instead default pulldown!), causing issues.

CTXz / stm32f1-picopwner

Dump read-out protected STM32F1's with a Pi Pico - A Pi Pico implementation of @JohannesObermaier's, Marc Schink's and Kosma Moczek's Glitch and FPB attack to bypass RDP (read-out protection) level 1 on STM32F1 chips

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Enable nRST pullup (Instead default pulldown!), causing issues. #5

Closed deividAlfa closed 1 year ago

deividAlfa commented 1 year ago

Pico's input default setting is pulldown! This makes a voltage divider against the nRST pullup in the STM32- I was getting 2.7V, others got 1.2V... this will cause random behaviour, might work for some and not for others.

Fix this by enabling the RESET pin pullup so it sits at 3.3V.

CTXz commented 1 year ago

That's a good observation! I'll merge this sometime early next week along with a few dump.py related fixes.

I suppose the variety in voltages is the direct result of which pull up resistor has been used on the STM device's PCB then, unless the STM32's internal PU's or the RP2040's internal PD's vary between models.

Thanks for the PR, Cheers!

deividAlfa commented 1 year ago

Attaching fixed Pico fw so people can use it until you make the next release.

attack_pullup_fixed.uf2.zip