bypassing the clock doubler also means bypassing the as/dtack and e clock logic. That would require quite a few extra multiplexer chips. Just disabling fast ram is quite easy to do and although not perfect, would make the machine almost stock.
I have been thinking a bit about the purpose of this little accelerator. I mean, the accelerator is fun to build but what to do with it in an A500?
I came to the conclusion that this accelerator is useful for those who want to keep a stock A500 for old-school games but sometimes want a bit more oomph for the more demanding games (dune II, upcoming Dread, Elite, etc). Then it is indeed important to be able to switch back.
What if we could disable the fast ram by holding ctrl-amiga-amiga for longer than usual.... (does anyone know the 555?
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