[sdiy] OT: COSMAC Elf 2000

[Roy J. Tellason]

On Wednesday 30 January 2008 14:45, anthony wrote:
> A while back I saw an article in Nuts & Volts magazine about the COSMAC Elf
> 2000.

Never heard of it,  but then that magazine is kinda hard to find around here 
anyhow,  for some reason.  Do you keep your back issues?

> At first I read the project article avidly, hoping for a cool project that
> might consume a lion's share of my vast TTL logic collection.

Dunno why.  "COSMAC" was a takeoff on RCA's original name for the 4000-series 
parts,  which they called "COSMOS",  later shortened to CMOS by most other 
folks.  It ain't TTL.

> Then I  get to the part where it says a lot of the logic was replaced for
> our circuit building convenience by a PAL or two.

Seems to me to be a pretty common practice on stuff that tends to use a lot of 
glue logic.

> So then I was totally soured onthe Elf 2000. This was one of the things I
> HATED about projects in Radio-Electronics: they'd hook you in with a cool
> sounding project and then you'd find it was centered around some wonderful
> new VLSI chip that my paper-route-having teenage ass couldn't afford.

I haven't read RE since the early 1970s,  but Populat Electronics did the same 
damn thing.  There was alway *something*,  some coil,  or some other oddball 
part that you couldn't do the circuit without,  and that wasn't commonly 
available in too many instances,  just from the author,  or a company that 
the author was running on the side.  I actually saw this spelled out 
someplace fairly recently,  though I can't recall just where -- where they 
said that this was how you really made your money,  not from publishing the 
articles.  Might've been on Don Lancaster's pages,  but I'm not sure.

> It was like they couldn't think up a lot of decent projects for kids like me
> who had scrounged a lot of parts from old radios & TV's.

Of course not,  they don't make any money that way...

> Of course the solution was to go to the local library (Logansport, Indiana
> at that time) and bug the basement clerks for all of their back issues of
> Radio-Electronics & Popular Electronics. My father had several of the latter
> and in the late 70's, they really knew how to put a few cool easy to build
> projects in their pages.

Sometimes.

> I think my problem was I was buying RE from the period 1985-1989 (and later 
> for a spell in the 90's when I was no longer a teenager).

Way later than I got any.

> So the point of this messge: I thought about it and figured I could probably
> make an Altair clone

Somebody's already doing that,  with a web site and everything,  though I 
don't have a URL handy at the moment.

> for cheaper than an Elf 2000 or even the original COSMAC Elf. I have all
> sorts of 74LS373's and 74LS374's and a few 8088's. I know that the original
> Altair was based on an 8086, but the switch shouldn't be too hard.

Nope.  The original Altair 8800 was based on the 8080,  which is a whole 
different thing entirely.  I don't have one of those but I do have an Imsai 
8080 here,  which also originally came with that part,  though mine's had a 
z80 board stuffed into it.

> It would be cool if I had some hex display Nixies (all mine are decimal),
> but a huge LED array and an army of 7-segment displays should work fine.

Hey,  blinkenlights are cool.  But I haven't figured out anything that 
justifies using a bunch of them yet,  nor the 7-segment displays I have 
either.

-- 
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"
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Information is more dangerous than cannon to a society ruled by lies. --James 
M Dakin