I wonder if a new simple ROM could be done, a small loop which would basically pulse each address line one by one...
.. Would probably have to wire DTACK low else it probably cause a BERR as not every address is used etc...
Also probably have to hardwire ROM chip enable to gnd as we dont know if GLUE decoding is even working right yet..
Though at least it would help diagnose things, as a small loop in ROM can just be 68000 code only, and address lines pulsing can be seen on the scope.. at least then we know the CPU is running as it should..
Probably just a bunch of reads from each address range into the CPU internal registers.. nothing more..
A thought for diagnostics
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exxos
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troed
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Re: A thought for diagnostics
Well we've seen bombs. That means, I believe, CPU is working, GLUE is working, MMU is working, Shifter is working.
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exxos
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Re: A thought for diagnostics
Only on one machine.. The other isn't doing anything, and I would imagine there are about 15 other boards out there to diagnose yet as well.
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