23 Jun
2018
23 Jun
'18
4:53 p.m.
> All the disk images for the Waveterm have been
created using programs
> written by PPG users. For some reason any disk we wrote with them
> wouldn?t read correctly in the machine itself UNTIL we made a new
> image of that disk using Teledisk 2.15 then re-wrote it back to the
> same floppy. My question is why should that make so much of a
> difference between working and non-working disks?
On Sat, 23 Jun 2018, Chuck
Guzis via cctalk wrote:
I'd love to be able to tell you, but I really
haven't fooled with the
thing for something like 17 years.
I had hoped that Chuck would have an answer.
If you have two disks that are nominally the same, and one works and the
other doesn't, then there is obviously something different.
If the sector contents are the same, then the next step would be to
examine the headers, gaps, and addressmarks.
For example,
if the gap after index pulse, before the first sector ofeach track is too
short, then it may not be able to read the sector header of the first
sector. (A serious and common problem with NEC-style FDC, not usually a
prolem with WD-style FDC)
Do you have a way to examine the raw track encoding?
I used a track read with a WD 179x (slightly modified "Trakcess" on TRS80
Model 3), and "TE" with the Central Point Option Board.
--
Grumpy Ol' Fred cisin at xenosoft.com