> this says 1024x600 and 256 colours

> I don't see where in the memory map there would even be enough space for a screen buffer that large to be located

1024 × 600 with 256 colours is 600 kB. Even in monochrome, it would be over 64 kB.

> but it looks like the LCD has to be bit banged by the CPU data bus directly?

Even at 20 Hz, that would involve writing over a ten million pixels per second, giving you about 1 CPU cycle per pixel ⇒ there’s no way to do that with this CPU.