I know pin D27 in the M-SoM M404x is used as SWDIO at boot, which pulls it high for a short period of time. However, I experience the same at shutdown, the pin is also pulled high. Is this the case for everyone, or might there be something else to it?
Hey @AntonCodex, I looked into this more and found that the SWDIO pin isn’t driven high, but is held high by an internal pull-up (40k) in the default/boot SWD configuration. This will likely hold true for soft reset conditions too.
The RTL872xD datasheet has PA[27] = SWD_DATA and shows its default pull-up/pull-down as internal UP when SWD is enabled via eFuse (which is true in this case).