On 2007-11-26, Martin H. Eastburn wrote:
I had hard sector floppy version of CP/M on my 8080B from Altair.
Hmm ... wasn't that machine called the 8800B instead?
I had gotten it from Lifeboat and it was on soft sector. But knowing
the hardware I could copy soft to hard and viola. Config time then!
Nice trick. Some controllers would only work with soft sectored
disks -- if the controller didn't see an ID sector, it would give up.
The hard sectors got more data on the disk -- but you lost flexibility
in sector size.
I remember having problems with the distribution floppy disks
for OS/9, and having to copy them to other disks (It turned out that my
only double-sided 5.25" floppy was suffering from a dying (and massively
overloaded) set of spindle bearings. They had used flanged bearings,
but ball and not designed for axial loads, but the pulley end of the
shaft was secured by a screw and washer into the end of the shaft,
compressing the bearings seriously, and then locked with Glyptal. I got
some replacement bearings and turned a spacer sleeve to go between the
inner races to keep the load down to a reasonable level, and that drive
became usable again.
In the meanwhile, the copies were done on a track-by-track
basis, and wound up totally scrambled because of different interleave. I
had to figure out how to unscramble the sectors before I could load OS-9
into the system -- from the 8" floppies which worked, not the single
double-sided 5.25" one which cogged and thus changed the speed enough so
the data was unreadable.
I had Forth as well and naturally Cobol, and extended Basic, and Fortran.
All this on the 8080 and it ran just fine.
The FORTRAN for the SWTP 6800 with SSB DOS-68 never worked for
me for whatever reason.
And no COBOL either. Lots of versions of BASIC, including
(later) ones with good random file access support, when DOS-68 got up to
a version which could handle that.
I created Fortran routines
for a company using larger mini machines. Nice to have home computing.
This was in the latter 70's. By Mid 80 the 8088 IBM PC floppy and Floppy/HD
came out. The AT was later an 8086 machine along with other business models.
Wasn't the AT based on the 80286, not the 8086? Yes, I agree
that the original PC was on the 8088 not the 8086.
And there *was* an 8088 based CP/M for the original PCs, but it
would not work on anything from 80286 on up. :-) I had one to play with
for a while. (Actually, I probably still have it somewhere.)
Enjoy,
DoN.
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