28 Dec
2010
28 Dec
'10
7:52 p.m.
On 28 Dec 2010 at 21:26, Jim Scheef wrote:
HP did everything it could to shoot itself in the
foot. After
promising compatibility among the 100-Series machines, the floppy
format produced by the 9114 driven by the HP110 Portable or the
Portable Plus was different from the format produced by the HP150.
There were clever format programs and device driver tricks to get
around some of these incompatibilities as well as to allow the PPlus
to make and use 3.5" floppies that could also be read and written by
regular DOS machines. Sometimes I find it amazing that HP has
survived!
Let's see,
HP-150 Series I: 66 cylinders, 1 side, 16 sectors of 256 bytes
interleaved 4:1),
1,024 byte clusters, media byte FA,
128 root directory entries.
3 sectors per FAT
HP-150 Series II: 77 cylinders, 2 sides, 9 sectors of 512 bytes
interleaved 2:1),
1,024 byte clusters, media byte FA,
128 root directory entries.
3 sectors per FAT
HP-110: 77 cylinders,2 sides, 9 sectors of 512 bytes
interleaved 1:1), but only 8 used,
1,024 byte clusters, media byte FB,
176 root directory entries.
3 sectors per FAT
HP Portable Plus: 77 cylinders, 1 side, 5 sectors of 1024 bytes
interleaved 1:1),
1,024 byte clusters, media byte FC,
96 root directory entries.
2 sectors per FAT
Yup, all mutually incompatible.
--Chuck