Re: 2 Macs + several apple2s, best way to xfer things ?

[bieling@terra.es (Jorge Chamorro Bieling)]

Michael,

I know. I must say that I have already read ("joyfully") almost
everything in your website. I did in 1983 a "local area network" card
for the apple II (it was called anka). It worked this way: the apple II
thought that anka was a disk controller card, so at boot time the
control was transferred automatically to the card giving it the chance
to install "its things" and returning afterwards to the basic prompt.
The schools where we intalled this had lots of apple IIs in the
classroom, but only the teacher's a2 had disk drives. From the teachers'
computer you could then send throught this network whatever basic
program you wanted to the apple II that you wanted or even to all of
them at the same time (kind of broadcast), and you could also interrupt
the children's apple II with a popup "window" and do a live chat with
him. In fact, even the children's apple's could do things like saving to
the teacher's disk or try to chat with the teacher. All this was done
via commands throught applesoft's & hook: "&+command".

I put in the card a 6551 uart (cloked by the 7MHz signal in the slot, it
was screaming fast) and kind of an "open collector" let's say...
"transmission line", and it made good use of interrupts so I believe it
was quite advanced in fact. I remember that everything was working
wonderfully and fine while in development and also when we first
installed it in a school, until the "boss" (the one who was paying for
it) came in to see it installed and turned on the classroom's
fluorescent lights. Suddenly all of the a2s started "clicking" (whenever
there was a comm-err the interrupt routine clicked the speaker once to
let you know)... Well, in the end I had to write some more
error-correcting code (everything was assembled with one of the first
versions of mike westerfield's orca/m) and remove the comm-err "clicks".
I would have liked to switch to a differential transmission line, but
there was no time for this and the cards where already built and
assembled...

This surely explains why nadanet interested me so much...

Regards,
Jorge.

Michael J. Mahon <mjmahon@aol.com> wrote:

> Jorge Chamorro Bieling wrote:
> 
> <snip>
> 
> > Also found Mahon's NADANET... what's that ? almost
> > 30 years later and there's still people doing things with the apple2s..?
> 
> Greetings!  Glad to hear that you've revived your Apple ][+.  ;-)
> 
> NadaNet is an "almost wire-only" network for Apple II machines.
> It does not support IP or other "standard" protocols, but it does
> support inter-machine PEEKs and POKEs of arbitrary data length,
> and the ability to invoke code on other machines.
> 
> It was intended as a platform for parallel computing experiments
> (which are really about algorithm decomposition, and not about
> performance).
> 
> It has been used as the basis for an 8-computer Apple II "blade
> server" (called AppleCrate).  An 8-voice wavetable synthesizer
> application called CrateSynth has been written for the AppleCrate
> and some examples of its operation plus complete documentation
> are provided online on my web site.
> 
> If you have two or more Aple II's, and can build some small
> (16-pin DIP-sized) adapters for them, you can run NadaNet
> and play with it yourself.  (Actually, if you have a couple
> of Apple ]['s or ][+'s, you don't need anything but wire!
> Apple II's later than the ][+ require the little adapter
> because of changes Apple made to the pushbutton circuits.)
> 
> -michael
> 
> Music synthesis for 8-bit Apple II's!
> Home page:  http://members.aol.com/MJMahon/
> 
> "The wastebasket is our most important design
> tool--and it is seriously underused."