PC game with weak bits

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NRS
Posts: 27
Joined: Mon May 06, 2013 8:32 pm

PC game with weak bits

Post by NRS »

If a PC game (5.25 inch 360K disk) uses "weak bits" on purpose, will the tracks affect show up as "bad" in the UI, or will DTC recognize that particular scheme and display it as "good"? This might be a dumb question, but I noticed that DTC did display bad-CRCs-on-purpose in other games as "good".

The game is Boulder Dash 2, and every almost every single track on side 1 shows up as "bad", all on side 0 show up as N ("not in image"), and the game loads fine in both PC and JR versions. From debugging the code, it seems to read the same sector (sectors 10 or 11, even 360K disks normally only have sectors 1-9) several times, then comparing the results from all attempts and expecting them to be different. This is repeated on several tracks. Using a regular imaging program that reads only the regular sectors 1-9 from both sides' tracks 0-39 yields no errors whatsoever; in other words, the read errors could only have occured in the "hidden" sectors 10-11. Hence my suspicion that the read errors aren't media defects, but just the protection scheme.

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IFW
Posts: 3079
Joined: Mon Nov 08, 2010 2:42 pm

Re: PC game with weak bits

Post by IFW »

It depends on how the data fits the decoding. If it can be considered as part of sector header or data then it will show errors.
If it is outside the normal data areas (e.g. header gap, track gap) it will not be flagged.

NRS
Posts: 27
Joined: Mon May 06, 2013 8:32 pm

Re: PC game with weak bits

Post by NRS »

Ah, ok. In any case, I have already uploaded the game to the FTP.

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