[geeks] Crackpot project, need some guidance

[Shannon]

On 16-Jul-2011 13:43, gsm at mendelson.com wrote:

>> The problem was I could not find any Univac code and didn't feel like
>> writing my own and all the tools chains it might have had, so I
>> eventually gave up.
> 
> I had that idea in high school when I became enamoured with APL. Having only
> an HP2000 Basic system to use, I wrote an APL interpreter in BASIC. :-)

Nice.

On my Atari 8-bit machine, I never had the money for much software,
especially languages. I would beg/borrow/steal manuals from computer
centers and then write my own "clones" of the languages on top of a fast
German BASIC interpreter/compiler and some C and assembly at times.

I created a couple of my own languages.

Most of these were not fast, but they made the little machine "feel"
like a bigger one. Instead of just running things like most of the
interactive 8-bit stuff, I made programs that let you "submit jobs" like
I'd seen or read about on larger machines, to make it feel like I was
playing with a big machine.

One program I wrote was sorta like my own little "Atari JCL". You
submitted a job that included a program, input file, output file. It
would take that and "compile" the program, run it, and generate the output.

I even made it print out mainframe-like job records on my noisy little
dot matrix printer.

Totally useless of course given the little machine was fast for an 8-bit
just using "normal" software, but I wanted a mainframe not a little home
computer :)

Eventually I even had a multi-tasking OS running on it, and had 3 basic
tasks running: BASIC/SpartaDOS, Textpro, my "mainframe" job scheduler.
It also did background printing with some page 6 hacking.

The OS basically did little but split up to 3 jobs into different bank
switched 64k chunks and it was fixed time slices if I remember right. In
other words, it slowed you to 33% of the machine speed because an idle
task could not "yield" the CPU. I think later they might have even fixed
that, but by that time I had moved on to Motorola 68K stuff.