hardware - How did Mode 3 on the Amstrad CPC work? - Retrocomputing Stack (http://retrocomputing.stackexchange.com/questions/1024/how-did-mode-3-on-the-amstrad-cpc-work/)
Quote from: Gryzor on 07:53, 17 September 16
hardware - How did Mode 3 on the Amstrad CPC work? - Retrocomputing Stack (http://retrocomputing.stackexchange.com/questions/1024/how-did-mode-3-on-the-amstrad-cpc-work/)
A careful look at the colourMux and VideoControl pages of the GA schematic (http://www.cpcwiki.eu/forum/amstrad-cpc-hardware/gate-array-decapped!/msg133284/#msg133284) will give the answer for the color decoding :
The mux only knows about mode 2 and mode 0. Everything else is mode 1.
For the pixel width (in VideoControl) only mode 1 and mode 2 are considered. Anything that is not mode 1 or 2 is mode 0.
"We'll never know exactly what happens until someone reverse engineers the Gate Array, and while it has been decapped and photographed in April 2016, so far I don't know of any available schematics."
Funny he should say that... ;D
Gerald reverse engineered the ga based on our decap pictures and it's pending check against real hardware. You can see the schematics in the hardware/gate array decapped thread.
Maybe someone with an account there could let them know :)