So I was pretty sure this didn’t work. I got my adapter board a while back and plugged it in and no dice… the ribbon cable got warm suggesting something was up and I unplugged. Fortunately nothing damaged.
I then took another look and realised I had routed one of the GND pins to the ‘wrong’ GND (as labelled) on the monitor… so I ordered a new board with this ‘fixed’ and tried again… but still no dice, the exact same problem.
I was about ready to give up, but figured I best stare at the PCB again and double check everything. I went through it, carefully checking the pins went to the right place, which they looked like they did… as a last ditch I thought I would double check the ‘pin 1’ of the monitor connector corresponded to the schematic I was using and what would you know it wasn’t… I had literally been wiring the whole thing up ‘back to front’ - pin 1 into pin 30 and vice versa.
So I fixed that and ordered a new board. It came this morning, plugged in and worked!
I’ll share the EasyEDA files when I have a second, but this will not work for all 30-pin displays, only those with the same pin configuration as the one I’m using.