#33 cbmformat/cbmforng "mysteries" bug: 1541-II, JPN Corp. mech.

[Womo]

In parallel to the reported "1571 mysteries" bug for the OpenCBM formatters, there seems to exist similar behavior, when the formatters are used with a 1541-II disk drive that contains a mechanism from JPN Corp. See also:

http://sourceforge.net/tracker/index.php?func=detail&aid=1467581&group_id=122047&atid=692219
http://sourceforge.net/tracker/index.php?func=detail&aid=1467583&group_id=122047&atid=692219

With the 1541-II (JPN Corp.) and either cbmformat or cbmforng, the formatting process produces "SYNC fail" conditions for several tracks. This leads to many repetitions. Mostly the disk format is aborted after 5 such failures.

This was tested with one 1541-II mainboard and two different JPN Corp. mechanisms connected to that board.

With the 1541-II (JPN Corp.) the bug can be worked around by giving the "-c" option. No other options has a similar influence on the error result.

In contrast, the 1571 mysteries bug could be worked around by using the "-o" option. Therefore it is suspected that the real source for the 1541-II (JPN Corp.) bug is different to the one from the 1571 drives.

[Womo]

Today I got another 1541-II with JPN Corp. mechanism, here it is named "Digital Systems Inc., model: DS-50F". The formatting failure symptoms are as following:

With the next generation formatter, the process fails as described above with:
cbmforng -sx 8 disk,id (aborts somewhere at track 24)
cbmforng -vsx 8 disk,id (aborts after track 16)
cbmforng -vosx 8 disk,id (aborts after track 28)

Formatting ends without abort for higher retry counts:
cbmforng -vsx -r 20 8 disk,id

The old generation formatter works better and does not abort with this mechanism, but several tracks need a second formatting try:
cbmformat -vpsx 8 disk,id (no abort)
cbmformat -vopsx 8 disk,id (no abort)
cbmformat -psx 8 disk,id

[Spiro Trikaliotis]

Moved over to github https://github.com/OpenCBM/OpenCBM/issues/45