I designed a small PCB featuring a STM32L011 and 433.92MHz ASK transmitter; planned as a dual-contact door sensor (those seem to be rare).
I connected the board to my BlackMagicProbe which (with assert_srst = scan) can detect a Cortex M target but then consequently fails to attach to it ('failed'). Trying to connect via my STLink v2 using ST-LINK Utility in several configurations does not even detect the chip.
Clearly I'm missing something. But what? :/