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Old 18 June 2016, 00:25   #436
Join Date: Jun 2010
Location: out in the wild
Posts: 1,129
Nope, I didn't surpass yours (your benchmark shows higher performance despite lower clock), because my memory is SD-Ram at 85MHz. This clock speed is just over the edge of a timing trick that I'm using on my 80MHz memory controller, so I need to add one clock cycle in order to have stable memory.

In other words: I'd be faster if my base clock would be 80MHz (thus CPU would be clocked at 40MHz), but that would mean slower chipram access. My original intention was to only go up to twice the board speed, and I have chosen the crystal frequency to be 3 times that clock rate. At 28MHz, all times are pretty much ideal, but the board infrastructure just wasn't designed to run with a CPU speed of 42MHz. Just because I didn't expect a 68020 to go that fast :-)

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