this post was submitted on 23 May 2025
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With displays like these, it’s either parallel or SPI. Try to find a chip in the kapton circuit, that is the actual display driver.
Try to find out the FPC pinout, there should be two pins for backlight, find out of there’s any GND, etc… my gut says this is some kind of SPI based controller, 24 pins is too little for a parallel one.
I did try loading a driver for a commonish chip, ST7789v, and operate under the assumption that it was SPI, but so far nothing but a white screen. I did try cycling through all the pins past pin 7 hoping one of them was the one for MOSI (Driving with a RPi 0)
A lot of those "Close but not quite" SPI displays seemed to share pins like Reset was commonly pin 4 and CS was 5.
I did trace that pin 1 is def BL led + and pin 2 is ground and I'm guessing pin 3 was 3.3v
But so far, nothing but white screen
I tried to peer through the FPC with a bright light looking for a chip, but couldn't find any. Fairly certain it's on that little strip of green PCB but it might be covered by that black goo. The only thing I was able to make out was in that pic with the "T24QV1-S"
I know parallel comes in 8 and 16 bit flavors, so I think there's enough pins for 8 and I could have sworn I saw 24 pin 16 bits listed, but maybe not