I have a consumer device that I know uses a STM32 microcontroller that I'd like to hack a bit. Is there a reliable way to communicate with the chip and determine its exact model, so I can locate the correct datasheet? Nothing is printed on the chip itself.
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3\$\begingroup\$ Use a debugger to connect via SWD. \$\endgroup\$– KartmanFeb 4, 2021 at 3:14
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\$\begingroup\$ That's what my research has shown, but surely not all STM32s have the same pins, right? \$\endgroup\$– JonahFeb 4, 2021 at 15:41
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\$\begingroup\$ Package and at least a guess of the STM32 family would narrow the search. \$\endgroup\$– Andrejs CainikovsFeb 5, 2021 at 18:54
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\$\begingroup\$ I got a ST-LINK V2, and the ST-LINk Utility seems like the correct program. However I'm having trouble getting it to recognize that I've connected it to the SWDIO/SWCLK/VAPP/GND pins. Still trying to troubleshoot. \$\endgroup\$– JonahFeb 14, 2021 at 5:00
1 Answer
I ended up buying an ST-Linkv2 and connecting to the SWD interface with some tiny clips. However the programmer refuses to detect the presence of the device. It seems likely that readout protection (RDP) is enabled, preventing access to the flash memory. Short of some sort of vulnerability, there's no way to determine the exact model, let alone re-program it.