The details are in the linked article. It works in the Apple II, Commodore PET and they use it in old chess computers too. Speed bump is only internal, communication with the antique is slowed down.
I didn't actually look at the article.. and I'll usually jump on anything 6502ish.. anyhoo.. that makes it sound a bit like the old accelerator cards
for the Apple II at least anyways. They used to be system on a card, although this would be system on a chip. Actual useful system speed could vary
wildly. It could usurp the system by asserting the DMA or interrupt line not sure which now, at which time it could run full boar, but access to the
system BUS required a return to 1Mhz as did video refresh. So there's kind
of a diminishing return the faster you go.
Spec
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