I have a crasy idea - I want to have my model railroad trains get real destination displays. I am using TT gauge, so 1:120 scale. I would need some display 15-22 mm long and 3-4mm high, without serious framing and requiring as little wiring as possible (I2C or similar). Maybe text only. As a controller I thought on digispark or pico...
The train decoder has exits which can toggle depending on direction, or exits which could be used to select the destination. Even a primitive serial like protocol like (exit one on - listen up!, exit one toggling up and down at 0.1 s intervals to get the code through) possible.
The displays would be in both cabs where the destination is shown on real train, and also if possible on the sides, where the regular trains also have the destination displays.
Any suggestions on such displays?