On Thu, 18 Jan 2001, Wayne M. Smith wrote:
> My S/23 Service Manual states that two 8 inch drives
> were available, the 31SD which was a single sided FM
> only drive, and the 51TDF which was a double sided FM
> or MFM drive. The disks have 77 tracks per side, and
> data can be written on tracks 1 through 74, with 00
> reserved for labeling and 75 and 76 for replacement.
>
> Both drives are hard sectored. FM disks can be
> formatted with 8, 15 or 26 tracks, with 512, 256 and
> 128 bytes per track respectively. For MFM the bytes
> per sector are doubled.
I believe that you mean SOFT sectored, as the number of sectors
per track in a hard sector disk is determined by the disk and
is only changeable by using a disk with a different hole pattern.
FYI, 5.25" disks came in both 10 and 16 sector hole patterns,
while 8" were 32 hole only to the best of my knowledge.
- don
> Using 256 bytes per sector, this gives you from 284K to
> 985K per floppy depending on drive/floppy type. This
> data corresponds exactly to the data on the
> displaywriter disk drive found at :
>
> http://home.planet.nl/~tresmont/ibm-hall.htm
>
> Therefore, I think must use the same format. For what
> it's worth, the displaywriter disk drive looks almost
> identical to the 5246 unit that goes with the S/23.
>
> -W
>
>
> > I was told that it was the same as the System 36, and
> possibly 23 also.
> > We were talking about that when be got an old IBM
> disk archiver. I
> > haven't looked into it any further than that, though.
> >
> >
> > On Wed, 17 Jan 2001, Joe wrote:
> >
> > > Does anyone know what disks format the IBM
> Display writer uses?
> > >
> > > Joe
> > >
>
>
>
Received on Thu Jan 18 2001 - 13:56:36 GMT