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In the MS12 controller board, we got debug capability through PA13 and PA14, which give us debug capability over SWD. This is what the connector looks like:
There's the PB6 and PB7 ports that are used for re-flashing. Here's what the data-sheet has to say:
Page 53 Reference Manual
Embedded boot loader
The embedded boot loader is located in the System memory, programmed by ST during production. It is used to reprogram the Flash memory using one of the following serial interfaces:
USART on pins PA14/PA15 or PA9/PA10
I2C on pins PB6/PB7 (STM32F04xxx, STM32F07xxx and STM32F09xxx devices only)
USB DFU interface (STM32F04xxx and STM32F07xxx devices only)
What are we using? NEITHER! We use gdb to flash.
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