Bret McGee

Been away from home over the last 2 weekends so not much to report.  Scanned two more disks tonight to get the rig back up and running; one had a dirty great finger print on it so another bit of cleaning needed; the other needed a couple of extra spins on...

Not much to report; 3 more disks scanned and everything OK.  Total 64/64. One handy thing about doing this is that at least I now know with a pretty high degree of certainty what Workbench disks are original.  I have got a number from eBay and indeed from my own...

Scanned 11 more disks.  The Amiga even had trouble reading a couple; tried in DF1: rather than DF0: and that did the trick.  Also had to clean 2 of the disks with Isopropanol again.  11 disks scanned OK and matched; one disk needed a couple of extra rotations to read,...

Hm.  These two disks are now 100%.  I have just re-captured both of them and they went through first time.  The sector on the original capture was miles out, 2us for example.  I was having some trouble with the Logic device, complaining about not being able to capture at a...

A total of 50 disks have now been captured.  One disk would not read on the Amiga but a bit of isopropanol and a cotton bud soon sorted that problem.  I appear to be having trouble with 2 of them, very old disks (Workbench 1.3.2 and The Very First). I...

15 disks scanned and hashed on the Amiga.  The same 15 disks scanned and hashed from the Logic captures.  100% match. Total: 26 of 26 disks appear to decode OK.  Next steps: capture more disks!

The MFM decoder logic has now been adjusted to take into account the last bitcell width.  If it's too short it will knock 125uS off the current bitcell.  If the last bitcell was too long it will add 125uS to the current bitcell. Success!  All 10 disks have 100% block...

The table below shows a snippet of block 655 on the "Copy" disk and the "CopyOfCopy" disk (on the right).  It's the dreaded 5 and 7 microseconds.  Slap bang in the middle between valid bit cell windows.  I did the obvious thing and adjusted my code to accept these values...