Hi!
I have problems programing my custom board, I'm using a STM32F446RCT6, and I couldn't establish a connection with my board, neither from STM32CubeIDE nor STM32CubeProgrammer.
after a lot of time trying to debug the problem I found out that actually I can establish a connection (an program) the board, but only if I'm pressing two very specific buttons.
The buttons were designed as general purpose buttons, but it seems they are connected to PB3 (JTDO) and PB4 (NJRST). We thought this pins could be configured as GPIO as well, but it seems something in the way those pins work is causing trouble.
In the reference manual it states:
"
The debug pins are in AF pull-up/pull-down after reset:
PA15: JTDI in pull-up
PA14: JTCK/SWCLK in pull-down
PA13: JTMS/SWDAT in pull-up
PB4: NJTRST in pull-up
PB3: JTDO in floating state
"
I'm assuming this is the problem; but I don't know if there is a way to configure PB3 and PB4 as GPIOs from the start in order to program the board correctly.
Tank you in advance!
