Screen 2x2 and 8x8

[Acerixx]

Bundled frame for 2x2: [refresh, write, 2bit pixel address, 4bit red component, 4bit green component, 4bit blue component]

Bundled frame for 8x8[refresh, write, 6bit pixel address, 8bit brightness]

Addressing designed with @PlayerWithoutName

[PlayerWithoutName]

Quick follow-up on this feature:
For a color screen, basically you can set a 12bit color of a pixel, addressed by 2 bits using a write bit, and then, you can update the screen with first bit. This is designed like that, so you can refresh a whole block after updating 4 pixels (and whole screen if you do this correctly).

Same goes with 8x8, but this one is monochromatic, i think it could be colored like the 7-segs and 2-character ones, but basically monochromatic.

[asiekierka]

Proposal: 16x16 [refresh, write, 8bit address, RGB222].

[PlayerWithoutName]

8x8 with 3bit per component is also an option, but less pixels per block will be more updatable (you can achieve 2Hz full scan and ~3.5Hz with interlacing with 2x2), and yes, you could use 4 pixels as one, but you'd have to sacrifice color depth. Everything depends on what is more desirable, higher pixel density or refresh rate.