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Quick update, i have assembled the board without the fast ram to test the cpu/clock doubler.
Unfortuntely it doesn't work properly yet. AS/DTACK and E/VPA/VMA timing looks great but somehow the boot process stops after the first drive click and I am left with a white screen. It looks like the cpu is then halted and only processes interrupts.
It does boot into chucky's diagrom though. Graphic/sound/keyboard all works fine. Memory test I don't understand fully (shadowram?) but what really goes wrong is cia test and drive tests. Cia's run too slow according to the test (especially the hsync one) and sometimes the system even crashes on that part. Now, at this point I am suspecting interrupt timing. Interrupts might be sampled too early by the 14mhz cpu and triggering the wrong interrupt levels. Does this make sense?
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