> > The "FIXED BITS" message is not at all mandatory. It's just a helpful diagnostic
> > produced by MAME's romcmp tool, which can only catch a few types of common dumping
> > errors. Depending on the hardware, some romcmp errors might not even be errors:
> > oversize ROMs are common and graphics ROMs and bipolar decoding PROMs might not
> need
> > all the data outputs that the part has.
> >
> > A few types of dumping errors romcmp can't detect but have occurred:
> >
> >
> > One or two bad bits (as in Sky Army).
> > Fixed bits that extend only through certain areas of the dump. (I've patched a few
> > cases of this by hand.)
> > Bridges between address lines that cause 3/4 mirroring (as happened with the Eeekk!
> > color PROM).
> > Faulty internal latches on 8048, 8041 or related MCUs.
>
> doesn't detect combinations of data lines shorting each other out either (which
> happened on a recent dump from Sean, that I thought was encryption at first)
Have we added the most support we can to romcmp or would it be possible to add more support for situations such as these?
- Stiletto
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