Weird problem writing 'weak flux' pattern
#13
The rotation of the data will work for all cases *except* disks where they locate a header, step the head, and expect the data to be exactly what is needed (track skew protection).  I ran into quite a few cases of this with the Supercard Ami for the Amiga (which handled this), and this is why I have a SPLICE mode for the SuperCard Pro.

Typically, you don't need to introduce any type of randomness for weakbit data - just write the data you get. If the flux is invalid, it will remain invalid.  Most all .scp images being used in UAE are single revolution, because almost all commercially produced disks were index aligned.   As you know, bitcells are spooled in under WinUAE and the number of bitcells is almost always not an exact even number for decoding to MFM, so that shifts the data by one bitcell (back and forth), which is enough for weakbit protections to see changing data on every revolution.  I have not seen a single weakbit protected game for the Amiga have a problem.  Same holds true for strongbit protections.  Trust me, I tried numerous types of protections that I thought might be a problem, and so far I have yet to see a single failure with anything.  You did a great job with that code.
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RE: Weird problem writing 'weak flux' pattern - by admin - 02-07-2016, 09:04 AM



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