Funny problem with STM32 based core - stuck in bootloader mode

[philetaylor]

Hi.

I thought I would let you know of a funny problem that I had yesterday and hopefully save somebody else the hour or so of hair pulling I had yesterday :)

I am working on a new display for one of my MIDIbox projects and once I had built the board, I connected it to my CORE32 and 'weirdly' the CORE32 wouldn't boot. When I started MIOSStudio, I noticed that the core was in Bootloader mode (the bootloader jumper was definately open!!!). When I disconnected the display board it booted fine.....

After a lot of checking and re-checking I looked at the circuit diagram for the CORE32 and noticed that the RW pin of the LCD connector (J15) is shared with the bootloader jumper and sure enough, a quick check of my LCD board with a magnifying glass, I found a tiny solder bridge between RW and Ground. This made the STM32 think that the bootloader jumper was closed so it didn't boot, removed this bridge and it booted fine!

Hopefully this may help somebody else in the future :)

Phil