On Fri, 8 Sep 2017, Chuck Guzis via cctalk wrote:
Yes, they were glued. Sometimes you can look carefully at the hub and
the cookie and match up remaining glue deposits. In the case of a
simple PC-type read, the position of the index doesn't really matter for
reading--as long as the sector headers are correct, you're fine.
"Normal" "simple" PC-type read, such as
COPY source destinat
CAN have a big problem. If you put the bub back on, so that index is
right in the middle of a sector, then that sector can't be read (with
NEC-type FDC, unless you "mask-off" the index signal). Likewise, if index
is too close before the beginning of the sector. NEC-type FDC does not
want to read/write immediately after index.
This is particularly true if you use a whole-track reader than can read
tracks without regard to index.
A whole track read, that ignores index would do just great.
WD 179x has a usable TRACK READ
It should be easy to read Amiga using WD 179x.
Unfortunately, NEC didn't implement THAT. They provide a
"READ MULTIPLE SECTORS", instead of "READ TRACK".
DISK2FDI, ADFREAD play some strange games (such as switching drives in
the middle of a read!) to trick the NEC into reading track.
I don't know about Amiga, however.
Amiga seems to be MFM, without IBM/WD style sector headers.
Amiga appears to read track and then parse sectors in memory.
--
Grumpy Ol' Fred [email protected]
