Wolfgang Moser wrote: > Hello Pete, > > Pete Rittwage schrieb: >> Hi guys, >> >> With the help of "TeaRex" on my forum, I added a simple way to >> read/write disk images using the index hole sensor built into the >> 1571. Through this addition, a revelation occurred. >> >> We had always assumed (since the 80's) that the Electronic Arts' "fat >> tracks" protection had 2 tracks (34 and 35) perfectly aligned. I >> added the index hole code and wrote out the disk perfectly aligned to >> track 0 and thought it was beaten. :) >> >> Well, it turns out this assumption is *not* true. When reading >> against the index hole, track 35 is actually skewed back 1/4 track or >> so on all the original disks. If I write it back out skewed in this >> way, it boots. These were never "FAT" tracks at all, just a specific >> track skew between two identical copies of a track. > > can you poove that observation with my cbmrpm41 tool (currently > available through OpenCBM CVS only)? Job mode 2 measures out relative > track synchronization regarding the the relation of two "neighbored" > sector numbers between the two tracks. You can advise cbmrpm41 which > sector to choose and also limit the measurement to these two tracks: > > cbmrpm41 -j 2 -b 34 -e 35 -c 2 8 Hi Womo, That tool doesn't seem to work because track 35 has CBM errors (it is a copy of track 34 so it has the wrong sector ID's for track 35). -- - Pete Rittwage http://rittwage.com Message was sent through the cbm-hackers mailing listReceived on 2009-03-23 02:59:40
Archive generated by hypermail 2.2.0.