8051 / EFM8LB1 / programming via C2 after PCON0.STOP := 1?
seems like it is possible to &quot;brick&quot; a EFM8LB1 and EFM8UB2...
https://www.silabs.com/community/mcu/8-bit/forum.topic.html/efm8ub2_efm8lb1_noc2afterstop-PSub
not even a power-on-reset delay of &gt;3msec helped in my case:
https://skybluetrades.net/unbricking-efm8ub3-thunderboard/
-arne