Thanks for the image, Chema! Things getting more mysterious for me
...
But first sorry for my bad suggestion in my previous post, that FloppyBuilder doesn't implement interleave - I wrongly mixed the 'geometry' value with the 'interleave' - they are completely different things.
I compared your test image 'B7en.dsk' with the official one '
B7en-1.1.dsk'. I found some differences in boot sectors and loader - this is OK, but what puzzles me, there is obvious difference in the GAP2 for each sector - in the 'official' image it's
filled with the correct value 22 x 0x4E, and the test image has
22 x 0x22. More strange is that this wrong value exists in all versions of FloppyBuilder, even more I found that the origin of the code is in 'old2mfm.c', where someone for unknown reason commented out the right value and changed it to 0x22:
Code: Select all
/* for (i=0;i<gap2-12;i++) trackbuf[offset++]=0x4E;
*/ for (i=0;i<gap2-12;i++) trackbuf[offset++]=0x22;
Although I think this is bug in FloppyBuilder, the images are working fine in emulators and writedsk2, but I'm curious how did you generate the 'offical' image with correct GAP2?