26 Sep
2005
26 Sep
'05
3:37 p.m.
On 9/25/2005 at 10:34 PM ard at p850ug1.demon.co.uk wrote:
Indeed I haven't.
Since both 720K and 1.44M 3.5" disks (on a
PC) rotate at 300 rpm, I am
trying to figure out why you'd want a 360rpm 3.5" drive. I've never seen
one...
(600 rpm is another matter...)
You've obviously never run into a NEC 9800 PC (or just about any other version of Japanese MS-DOS) diskette. 77 cylinders of
5x1024 sectors,
spinning at 360 RPM, just like an 8" drive.
I am puzzled as to why that would spin at 360rpm. The format would be
possible on a '720K' drive turning at 300 rpm using the normal 250kbps
double-density data rate. If you double the data rate to 500kbps, you
should be able to get more that 5 sectors, even at the faster spindle
speed.
What was the data rate at the interface connector of these Japanese machines?
Most USB drives understand this format automatically.
Not having got anything that supports the useless serial botch interface,
I've not looked at such drives.
-tony