GameToy hardware project

These pages describe a sort of blog-ish time log on my 'GameToy' hardware project (stalled indefinitely).

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June 7th, 2006 - Pete

And we're, so to say, in business (webcam image again):

After all the frustration, what fixed the graphics output was switching the "read status please" and "write data please" signals.

|Data sheet|What I do|What should happen| |RS|R/W|D/I|R/W| |L|H|1|0|Status read| |H|L|0|1|Write display data| |L|L|0|0|Command mode| |H|H|-|-|Read display data|

Apart from that, there's still some timing issues, but they seem to be under control at the moment. I'm not reading from display, hence the signals are undefined, but the above table explains how the commands (like "turn display on") seemed to work although data did not get written right.

So which is it, is the data sheet wrong, or did I mix the two wires? I'm fairly certain that my wiring is correct, as I've rewired the thing multitude of times. In any case, it seems to be working now.

Comments are appreciated.