My drawings for z80 display.
It will use paralell comunication with z80, there is not any PIO.
I will replace 2 logic chips with some signal diodes-1N4148, to keep as low amount of chips as possible.
Diodes will also make wireing little bit simpler.
I think, I will use 5mm red leds.
I expect total cost of this display, to be around 7€-i already have wood for housing, like making boxes out of wood.