24 Jan
2018
24 Jan
'18
3:17 p.m.
On 01/24/2018 02:35 PM, Glen Slick via cctalk wrote:
On Wed, Jan 24, 2018 at 9:45 AM, Fred Cisin via
cctalk
<cctalk at classiccmp.org> wrote:
Yes, the intel 82077 datasheet should tell you all you need. One aspect
is that if you're operating in 1Mb/sec mode, you need to set
perpendicular mode in addition to setting the 1M data rate, so not
altogether straightforward.
--Chuck
Does ImageDisk or Teledisk support it?
If so, then with the ED controller and one of these drives from Chuck, you
could image things such as the "4 Meg" floppies from NeXT. (4M is the
UNFORMATTED capacity of the 2.8M disk, and NeXT marketing thought that "4M"
sounded better than the "2.8M" formatted capacity)
The ImageDisk 1.18 source code is available to inspect to answer the question.
If there is something special that software needs to do to select a
1000K bps data rate I don't see anything in the ImageDisk code which
does that. What does software need to do to select the 1000K bps data
rate for 2.8M mode?