that near pin12, and watch out you dont hit the pin.
mini pinout
you than have to reflash tinybooterdecompressor via rs232 (not uart!).
be sure to flash the right one. if you wanna use rs232 for programming use the rs232 version, else the uart one.
mini firmware and short description how to flash it
edit: youd could also boot it in bootloader mode, it wount execute your app than, and you can delete it per mfdeploy (the erase button near ping)
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