8-bitters and multi-whatever
ajp166 at bellatlantic.net
Tue Sep 11 06:50:14 CDT 2007
>Subject: Re: 8-bitters and multi-whatever
> From: "Roy J. Tellason" <rtellason at verizon.net>
> Date: Mon, 10 Sep 2007 16:24:01 -0400
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>On Sunday 09 September 2007 16:04, Allison wrote:
>> >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.
>I remember seeing that in some sales literature and it always did strike me as
>being more spendy than I wanted or could afford to get into. :-)
It cost more because it was industrial strength, larger boards, regulated power
and so on.
>> >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 know of ARCnet, went to a short seminar on that once at a trade show, and
>in fact even have a couple of ISA cards around here someplace, though I
>don't forsee me ever using them.
ARCnet and most of the 'nets were in the price range of a hard disk then.
Also the whole idea of networking was new. For example in 1982 the two
largest networks I knew of were DEC (internal) and Dupont(internal) and
they were around 50 nodes!
There were a few simple schemes but excluding myself how many hobbiests
back then had two or more systems?
>> >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.
>What does that take on the software side of things?
Not a whole lot, CPnet could be used but it was easy enough to use plain
vanilla CP/M2.2 and add your own BIOS drivers for "networked functions".
defineatly home grown.
>> >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.
>Nope. It's just my particular fascination these days. And probably a lot
>easier to deal with than lots of big iron. :-)
>> >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?
>Just that I'd like to see some stuff that isn't oriented that way. You have a
>SBC, you obviously need some way to talk to it, but the standard "console"
>stuff gets a little old, I probably don't want to hook a printer up to it,
>and may not even want a disk drive of any sort, depending on what I wanna do
>with it. I'm up for exploring some alternative approaches to doing things.
>Unfortunately the embedded stuff that's out there doesn't satisfy too often,
>the design being too specific to the app, source code not available, etc.
>I'm thinking that it should be possible to have some sort of a more
>generalized framework to hang things on, and then you could optimize it for
>specific uses, or expand it in different directions. Even from the earliest
>days "personal" computers all seemed to take pretty much the same approach to
Well by hook or by grook the average PC still has a serial port, some have two
or atleast a USB port for a USB to serial. It's not that hard to write software
to use that serial as a access from the SBC for things like a remote printer
or disk and people have and are doing it. It's not "networking" in the full
blown sense but none of the IO of a SBC is required to direct connection
to a printer or terminal (ignoring rom based stuff).
>I realized in other messaging a while back that it's been well over a year
>since I fired up a soldering iron, and this is a bad thing. :-) And even
>then, it was a matter of scrapping stuff, not building anything new and
>interesting. I need to get out of that particular rut and get back to it,
>or there's no point to all those parts I've been scrounging for decades.
>Maybe one of these days I will...
When you do tell us about it. Seems these days I get to maybe one
of the major computer construction based projects maybe two per year.
But I split my time between RF projects and digital projects.
>Member of the toughest, meanest, deadliest, most unrelenting -- and
>ablest -- form of life in this section of space, a critter that can
>be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
>Information is more dangerous than cannon to a society ruled by lies. --James
More information about the cctech