[sebhc] USB for the H8?

[Lee Hart]

Lee Hart wrote:
>> more and more of my old 5.25" floppies are gradually dying.

Dwight K. Elvey wrote:
> That is partly why I've written the program I have. It copies
> images of the hard sectored disk to the PC. These can then be
> transfered to CDROMs or other storage media (preferably duplicated).

Interesting. I can readily see storing the data itself on some other
media (floppy, hard disk, CDROM, etc.). What I'm not clear on is:

a. How do you insure that you have correctly READ every single sector
   on the hard-sector disk, including normally 'hidden' data like the
   physical order of the tracks, sectors, and sides, preamble and
   postamble bytes, etc.

b. How do you put this data BACK onto some other kind of media so that
   an H89 (or H89 simulator) that may not actually have a hard-sector
   controller, 5.25" disk drive, or physical 10-hard-sector disk can
   use it? 

To put this in concrete terms: Suppose it is 20 years in the future. I
have saved all my H17 disks on a CDROM. I want to show my grandson what
it was like in the "good old days", and run my old bootable standalone
HDOS "Adventure" disk.

Suppose I still have my H89, and manage to fix it up and get it working
(at least as far as the H: prompt). But all my 5.25" disks are bad or
lost. How do I get that H17 disk image from the CDROM onto a real H17
disk?

Or, will I need an H89 simulator program that runs on whatever passes
for a PC in 20 years? Can it read and boot from that H17 disk image on
the CDROM? Does this program exist today, so I'd have a chance of
proving to myself today that these CDROM images can actually be used
again?

> I've been thinking about setting up a punch to make 10 sectored
> disk out of the pile of other floppies that I have...

That is a good idea. Soft-sectored 5.25" disks are at least 100 times
easier to get than 10-hard-sectored. I suspect that there are so many
pieces of legacy equipment that still use them that even in 10-20 years
these soft-sector disks will still be available. [An aside: A friend of
mine just sold an 8" full-height floppy disk drive for $350 to a machine
tool company that needed it to repair an ancient DEC minicomputer that
runs a milling machine they still use]

Or, if we can get a group buy of some NEW hard-sector disks; they should
have a reasonable chance of lasting another 10-20 years.

If I seem paranoid about this, it's because I recently went through a
bit of a crisis cause by this sort of thing. TMSI sold microcontrollers
based on the RCA 1802. This is an extremely rugged microcomputer, widely
used in military and aerospace applications. The NASA Voyager spacecraft
used them.

Today, the Voyagers are still working, still sending data from deep
space far beyond the orbit of Pluto. But due to budget cuts, layoffs,
equipment failures, and other problems, JPL has thrown out, lost, or
broken all their 1802 software development systems. Sure, they have
backup disks; 8" floppies, written in RCA's odd format that is
unreadable by other equipment. Sure, they wrote 1802 simulators; but
they had no way to test them to insure that they really did work
correctly.

So, I was one of a chain of about a dozen people that pieced together a
working RCA development system, so we could read the disks. Then write
the simulator, and verify that it worked correctly. Then translate the
various RCA development tools (editor, assembler, debugger, etc.) so it
was possible to modify the Voyager code, test it, and then upload it to
the spacecraft with confidence that it would work. It was a major effort
that took a couple years. But the end result was to extend the useful
life of the spacecraft, allowing it to slow down its data rates and
conserve power to continue operation despite the staggering distances
and various on-board system degradations and faults.

It's easy to assume that:

a) If it works today, it will always work.
b) If it breaks, I will always be able to get parts for it.
c) If I can't, it won't be hard to substitute something I can get.
d) I'll always have the documentation.
e) Even if I lose it, it will be on the web somewhere.
f) Or my memory is good; I'll remember how it works.

Microcomputers are turning out to be exceedingly fragile. Losing a page
out of a book, or a piece of a photograph isn't so bad; the rest is
still usable and you can often reconstruct the missing pieces. But if
anything is missing or wrong with a computer, the whole system is dead.
It can be very difficult to fix or salvage anything from them, unless an
effort is made to preserve EVERYTHING needed to maintain them.
-- 
"Never doubt that a small group of committed people can change the
world. Indeed, it's the only thing that ever has!" -- Margaret Meade
--
Lee A. Hart  814 8th Ave N  Sartell MN 56377  leeahart_at_earthlink.net


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