Quote:
Originally Posted by pandy71
CSG was incapable to deliver 35ns performance - ECS was already tricky and they need to use tricks as CLUT interleaving (efficiently reduce maximum number of colors to 4 selected from 64 not 4096). Lisa was made in sub-micron technology (0.6um AFAIR) so no problem with 35ns however with enormous amount of transistors when compared to other AGA IC's...
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Right, but why so many more transistors? What I was saying is that maybe they didn't just add features to the Denise design and do a die shrink. I'm speculating they just did a clean-sheet replacement, hence the lack of optimization.
Lorraine was developed by hand, without the benefit of smart ASIC design software. This meant years of work but super tight design. By the time AGA came into being, they might have used automatic logic generation software -- which was relatively new and rather inefficient at the time. That would be something to ask some of the old Commodore engineers that are still with us.