Happy DEC-10

[Paul]

Today being DEC-10 reminds me of how I got started in this whole mess.

--
Paul the Legacy Server
Full Recovery reached May 30, 2008
"People can be educated beyond their intelligence"
-- Marilyn vos Savant

[Steve VanDevender]

Paul <pssa...@comcast.net.INVALID> writes:

> Today being DEC-10 reminds me of how I got started in this whole mess.

When I started college I spent a lot of time on this multiuser bulletin
board system, actually based on a thing called COM, that ran on a
PDP-10. By the end of the year I had been invited to take part in
running the thing, including developing some custom modifications for
it which involved writing PDP-10 assembler.

I also got in a bit of trouble at the end of my first computer science
class because I used my own computer for coding and running the Pascal
programming assignments, and used the TOPS-10 account they gave me for a
lot of "R GAM:DUNGN". To the point that my CPU and memory charges
dwarfed those of the rest of the class.

--
Steve VanDevender "I ride the big iron" http://hexadecimal.uoregon.edu/
ste...@hexadecimal.uoregon.edu PGP keyprint 4AD7AF61F0B9DE87 522902969C0A7EE8
Little things break, circuitry burns / Time flies while my little world turns
Every day comes, every day goes / 100 years and nobody shows -- Happy Rhodes

[Juergen Nickelsen]

Steve VanDevender <ste...@hexadecimal.uoregon.edu> writes:

> I also got in a bit of trouble at the end of my first computer science
> class because I used my own computer for coding and running the Pascal
> programming assignments, and used the TOPS-10 account they gave me for a
> lot of "R GAM:DUNGN". To the point that my CPU and memory charges
> dwarfed those of the rest of the class.

During my first semesters studying EE, I took a "Pascal for EE students"
programming course, my first. Finally something more exciting than the
PET 2001 at school! And it was. NOS/BE on a CDC 175 felt quite strange,
but I loved that.

Finding the course programming tasks too easy and boring, I set on doing
a Game of Life; the block mode terminals connected to concentrators
emitted at max. one page, and on Enter the next, so you could page
through the generations. Yay! My programs were often aborted due to
excess of CPU time limit, but one of the tutors was so kind to show me
how to increase the soft limit.

A few days later, he came to me directly from the tutor's meeting; the
computing center had complained about the CPU usage by the course, and I
was explicitly forbidden to run my Game of Life program.

I had not known that the whole pipe between the CPU, some PPU, terminal
concentrators, and finally the terminal buffered *a lot*, and the CPU
was churning away while I was slowly paging through my generations. That
could have easily been avoided. A few weeks later, though, I discovered
the brand-new PC lab and made a new Game of Life using Turbo Pascal.

--
They that can give up essential liberty to obtain a little temporary
safety deserve neither liberty nor safety. -- Benjamin Franklin

[Steve VanDevender]

Juergen Nickelsen <n...@w21.org> writes:

> Finding the course programming tasks too easy and boring, I set on doing
> a Game of Life; the block mode terminals connected to concentrators
> emitted at max. one page, and on Enter the next, so you could page
> through the generations. Yay! My programs were often aborted due to
> excess of CPU time limit, but one of the tutors was so kind to show me
> how to increase the soft limit.
>
> A few days later, he came to me directly from the tutor's meeting; the
> computing center had complained about the CPU usage by the course, and I
> was explicitly forbidden to run my Game of Life program.
>
> I had not known that the whole pipe between the CPU, some PPU, terminal
> concentrators, and finally the terminal buffered *a lot*, and the CPU
> was churning away while I was slowly paging through my generations. That
> could have easily been avoided. A few weeks later, though, I discovered
> the brand-new PC lab and made a new Game of Life using Turbo Pascal.

Before I ever encountered the PDP-10 I spent quite a while in high
school writing and optimizing a Life program on an Apple ][ coded in
6502 assembler. Got it to the point where it could run at up to 50
generations/minute on a grid of up to 256x256 pixels, with a 96x96
scrollable viewing window. Might still have that lying around somewhere
on media I can no longer easily access. Much of the performance boost
was obtained through two techniques: translating a sort of "parallel
adder" coded in PDP-11 assembler that I found in a Byte magazine
article, and adding code to quickly skip over empty regions in the Life
grid where it was unnecessary to compute generational changes.