25 Jan
1999
25 Jan
'99
10:40 a.m.
Apart from that, there's a serious band of
PERQ-fanatics who can solve
just about anything you're likely to come up against and then some :-).
I like good documentation. Clearly, even if the original documentation was
abysmal, information is now pretty readily available. (I think you made
that point in one of your other posts.)
Sounds like an RK05 pack. I seem to remember the drive
looks like a Diablo
model 30 (for which repair manuals do exist). That would use the same
sort of pack as an RK05, but these packs are hard-sectored, and I have no
idea how many sectors an Alto is expecting...
I know the Alto drive is a Diablo drive.
Some Altos came with an option of one removable and one fixed pack. Both
packs have the same capacity. The access time is much lower than the
removable-only machines. (That could be average access time -- meaning that
the removable packs are the same on both kinds of machines. I'm just
quoting from a little table in the manual.)
Some also came with an external removable-pack drive. (The scale is some-
thing I'm not used to. I think of a device I can hold in my hand being
added to a machine that fits on my desk. Here we have a device bigger than
many modern computers being added to a machine that could BE my desk, if the
monitor were taken off the top.)
If you look at the Alto manual, you can see Diablo's model numbers.
Did all Alto machines have a chording keyboard? Or was
it an option?
Possibly an option. The I/O was very flexible but I suspect (drumroll) you
had to write your own microcode for it. :) And create a custom cable and
header. But it could actually have been standard.
The keyset is exactly as Doug Engelbart designed it: 5 bars next to each
other, a bit like piano keys. It doesn't replace the regular keyboard;
it's just an alternate way of entering small bits of data while you use the
mouse with your other hand.
-- Derek