8-bitters and multi-whatever

Allison ajp166 at bellatlantic.net
Sun Sep 9 15:04:25 CDT 2007


>
>Subject: 8-bitters and multi-whatever
>   From: "Roy J. Tellason" <rtellason at verizon.net>
>   Date: Fri, 07 Sep 2007 23:49:03 -0400
>     To: cctalk at classiccmp.org
>
>So I was poking around at bitsavers after snagging those TI databooks,  and 
>stumbled across some files pertaining to TurboDOS.  I'd read about that 
>before,  might even have some manual or other on it someplace,  but I've 
>never had the pleasure.  I do have one box that was supposed to be a 
>multi-user system, that being my TeleVideo 816,  which had TurboDOS as an 
>option but the one I have came with something called MMMOST,  which I wasn't 
>all that impressed with.  A guy was talking about sending me a tape but that 
>never happened.
>
>I remember hearing about one or two other packages that were similar (never 
>mind MP/M,  which I've also not messed with and don't get the impression I 
>want to bother with really),  but have never had the pleasure of running any 
>of them.
>
>A while back I *almost* got a hold of one of those "z80 network in a box" 
>systems,  it wasn't S-100 but something else I can't recall,  I think that's 
>the one I have the book on,  but I never did snag it.

Multibus, very nice bus and expensive cards.  I have a few multibus cards.
Intel used it in their MDS800 and a few otehrs as well.


>Unfortunately instead of RS232 Televideo has something else going there 
>(RS422?),  not easy to interface too,  and they distribute their "network" 
>out amongst what other Televideo boxes you have,  which in my case is none.  
>I guess with an S-100-based system you could always add more cards,  and 
>somehow or other make it work.
>
>And speaking of the networking aspect of it,  do any of you guys know how they 
>did it?  I recall one time getting a glimpse of some system or other that was 
>S-100 but also had a set of connectors at thet op of each card,  which is 
>what they used for their inter-processor linking rather than trying to push 
>it through the bus.  The reason for this is not apparent to me.

Many ways to do it, using a commmon port or a pool of common memory for
in box networking and serial ports as well. There were also ARCnet, pre 
Ethernet and even Ethernet.

>I've also seen some "CP/M networking" stuff referred to that was supposed to 
>work through serial ports,  which pretty many machines had,  althogh they 
>appeared in at least one case to be using diodes to wire-OR RS232 signals, 
>which doesn't strike me as too terribly robust.  And what software support 
>there was for this wasn't real apparent.

That was a poor mans networking.  Basically the serial ports were used as 
CD/CSMA bus and there was some protocal like Ethernet but slower and could 
use the usually common async chips.  I have such a net going for my CP/M crates
and all.

>I dunno,  I've just got this fascination for assorted 8-bit parts talking to 
>each other through some smallish number of wires,  I guess it's easier to 
>deal with than some of the big iron you guys handle regularly,  which I can't 
>afford to go get never mind housing.  And I've seen multiple processors used 
>in stuff already,  as in some musical equipment that passed "event 
>information" from one chip to the next with only a couple of pins,  or the 
>daisywheel printer that had _four_ 804x procesors in it for different 
>functions.

This is not a new thing.

>TurboDOS is neat,  and has some good design aspects in it,  but there's too 
>much legacy stuff in there for being able to run CP/M software,  stuff I'd 
>leave out if it were me  and too much emphasis on the same old Console / 
>Printer / Disk Drives in the system,  as opposed to something different or 
>unique.  I found the same thing to be the case when I looked at FORTH,  too 
>much of the usual stuff,  and that was supposed to have been used in some 
>control applications?  I must've missed something there...

????  Whats the question or point?


Allison




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