> > 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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