25 May
2003
25 May
'03
4:10 p.m.
Well, understanding these computers in an architecture
sense is one thing* -
but operating and maintenance skills were usually verbally transmitted and
rarely permanently documented. They can probably be redeveloped with
True, and even if they were documented, that's often not enough. You need
to have a 'feel' for the machine, or more exactly, you need to have done
it before.
experience but this experience is likely to be at the
cost of media damage.
One reason to always start with unimportant media...
Yes, I know that blank media for some drives -- particularly demountable
hard disks -- is difficult to find and expensive. But unless people do
continue learning how to run and maintain such drives, then knowledge and
skills will be lost for ever. To me, ensuring there's still one person in
the world who has aligned an RK05 from scratch was worth risking a disk
pack for...
I would put this the other way round - people who had a good understanding
of the old machines have some chance of getting a deep understanding of
modern ones. In terms of the Instruction Set Architecture and programming
It makes no difference which way round you say it. If you _truely_
understand a modern machine, then you'll find the older ones pretty easy
to understand. Conversely, understanding an older machine will help you
understand modern ones.
there are few difficulties in understanding one given
the other (but for
'minor' things like self-modifying code and the concept of overlays). On the
other hand, the lower level descriptions of the processor logic typically
use terminology that is totally foreign to the modern logic designer - not
to mention the implicit "wired-or" that is frequently used and not
explicitly mentioned in the documentation or that with only a small number
of logic gates per card techniques were used to minimise the number of gates
that would never be seen on modern synchronous logic.
The less said about so-called designers who have problems with any of
that, the better!
-tony