Hi, all,
Has anyone here worked with or ever plotted silently to create a moderish
7-segment decoder/driver from a GAL16V8? I'm working on a project made
>from classic parts, and am trying to reduce part count rather aggresively,
since I'm going to hand-wire it.
One thought was to attempt to combine a 7490 _and_ a 7447 in a single
GAL16V8. I have blown hundreds of PALs, but have much less experience
in designing with them, so I'm not even sure that it's possible to mash
together that much logic internally in a 16V8. I know all the outputs
are optionally registered, so presuming one has 4 assignable flip-flops,
one could theoretically make a counter on the output pins, but what's
less clear to me is if you could then take those terms and internally
decode them to a 7-segment display.
After the large amounts of replies about this 8-way digital switch, I
don't necessarily want to clog the list with discissions of what is and
isn't possible for a GAL16V8, so if you can remember, please make any
suggestions and comments to me directly, not the list.
Thanks for any nudges towards a solution.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 8-Dec-2007 at 15:40 Z
South Pole Station
PSC 468 Box 400 Temp -25.4 F (-31.9 C) Windchill -52.5 F (-47.0 C)
APO AP 96598 Wind 13.7 kts Grid 12 Barometer 678.8 mb (10674 ft)
Ethan.Dicks at usap.govhttp://penguincentral.com/penguincentral.html
I am in the process of rebuilding an IMSAI 8080 and am using my Mac Pro as a
dumb terminal. I have it all to the point where I can type a character and
see the ascii appear on the front panel. What I need to do is write a
simple 1st stage loader that will take the HEX output from the ASM80
assembler, send it over the serial connection and put it in memory. This
way I can write a more sophisticated loader and not have to key it in by
hand.
The question is, what is the algorithm, in assembly language, for converting
an ascii character to its binary equivalent. By this, I mean converting an
'a' to 1010, not 041H which is the ascii value. I remember writing such a
thing 30 years ago but simply cannot get my head around it now.
The algorithm has to deal with taking an ascii string like
AF67DBFF6FF9AF81C2130053DBFF5FAAC2210039D20600780747D3FFAF4 and converting
each ascii character into the binary value it represents. The sting above
would convert, one character at a time, to:
1010
1111
0110
0111
1101
well, you get the point...It has to work only for 0-9 and A-F which should
make it easier.
Anyone out there remember how to do this?
Jeff Erwin
A guy is offering me a pile of old monitors, he describes as "mono, cga and
ega", probably about a dozen or so altogether, and presumably all working.
I don't have anything that currently uses any of these interfaces running at
the moment.
Any interest in anybody taking these off my hands?
--
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
M Dakin
When I was at the VCF in Mountain View this past fall, someone in the
concessions area had an HP 87 computer/calculator for sale. Does
anyone remember who that was? I find I'm getting interested in the HP
8x series.
Thanks!
David Betz
>
>Subject: Re: Q-bus to CF [was: IOmega]
> From: der Mouse <mouse at Rodents.Montreal.QC.CA>
> Date: Fri, 29 Feb 2008 02:00:53 -0500 (EST)
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>> Generally IDE and CF (compactflash) are the same interface and for
>> Qbus-11 fairly simple. It's been done, however, the problem is the
>> driver as bare IDE or CF is NOT MSCP not is it DL, DX, DY or RK so a
>> driver is needed and noone has apparently stepped up to do it.
>
>Not quite true.
>
>Some time back (years), someone was working on an IDE interface for a
>Qbus MicroVAX and I was doing the driver. (This was not bootable; the
>idea was to netboot to get the kernel onto the machine.)
>
>We never got it working, and it is not clear to me, now, why not. I'm
>not sure whether this is because it wasn't clear why then or because my
>wetware memory has bitrotted - what memory I have indicates that there
>were hardware issues, but I had no physical access to the hardware, so
>I'm not sure that that's right even aside from bitrotted memory.
the likely reason is PDP-11 and VAX does read before write and IDE
does not like that. The fis is to make the READ address different
>from the write addresses, even DEC did that with interfaces.
It is otherwise straightfoward with the usual observance for timing and
the like.
Allison
>I once was one of two people who built a one-off Qbus board out of
>wirewrap, so I feel I ought to be able to build such a thing myself.
>Perhaps someday I'll gather the parts and try it. (Anyone have a Qbus
>development board looking for a home? :)
>
>/~\ The ASCII der Mouse
>\ / Ribbon Campaign
> X Against HTML mouse at rodents.montreal.qc.ca
>/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
Dan Gahlinger wrote:
> There *IS* a Vax named a "Saul" or "SOL", I've seen it.
> It's a "luggable" (so to speak) like the Rainbow, but it's a Vax.
> They existed, so don't insult my intelligence.
> And btw I've been doing Vaxen since 1976, so I think
> I know a thing or two about reading Ascii
> it's definitely "OS/2"
I think it's time for me to unsubscribe from this list and
get back to reality. Sure, let's make up names for already
existing products instead of figuring out what they are
(VS2000? VAXmate?) and then insist that that we've
been doing the VAX a year before it left the
factory, therefore OS/2 has to exist for the PDP-11.
Why do I even try to interject myself into this crap.
Tim.
Greetings,
Do you still have the TU58 tapes?
Mick Lindell
Sr. Test Development Engineer
GE Aviation
Digital Systems
T +1 616 241-8454
E Mick.Lindell at ge.com
3290 Patterson Ave. SE
Grand Rapids, MI 49512 USA
GE imagination at work
These commodities/technical data are controlled for export by the U.S.
State Department. They may not be transferred, transshipped on a
non-continuous voyage, or otherwise be disposed of outside of the United
States, either in their original form or after being incorporated into
other end-items, without prior written approval of the U.S. Department
of State.
As said before, one can easily get some of the small (8 pin dip) micros to do
magic things, but sometimes (as mentioned) it is a bit more trouble than it is
worth. Many of us (me!) have stuff in their junk
boxes^H^H^H^H^H^H^H^H^H^Hclassic part archive that will do the task quite
easily. In my case, I obtained a nice Facit 4070 paper tape punch and made up
a simple interface adapter (it fit inside one of those 2x DB-25 scramble boxes)
to make it function using a PeeCee parallel port. Now if I desire to punch a
paper tape, all I do is a simple copy to the printer port and ...buzzzz... out
comes the tape. Thankfully the Facit 4070 had some power available on its
DB-25, but I needed to play around with all the levels (it used 6 volt levels).
In the end, all it took was a single 74LS00 to do the trick on changing the
strobes to conform.
I suppose I could have used an 8 pin ATMEL chip, but why bother. Sometimes the
"classic" solution is MUCH easier.
I even built up a character font (5x8) so I could punch titles in the tape. Of
course, now I need to get the reader functional, but that is another story.
p.s. If anyone wants details on the interface, contact me off list.
--
Sorry,
No signature at the moment.
____________________________________________________________________________________
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I'd really like to have something like one of the old
mainframe/minicomputer control panels for my PC, but I'm just not sure
how to implement it. Anybody here tried something like that? Ideally,
you could power it on, see registers, toggle stuff into memory, have
lights for interrupts, that kind of thing. Yeah, I know, as soon as I
bring up an operating system, the ability to toggle things into memory
would be rather dangerous, but I just can't resist the charm of the
idea :)
So... doable? Impossible? Improbable?
John
--
Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn
YouTube doesn't stream. It slowly downloads the flash video files to
the temporary internet files folder where it's usually named "FlaXX.tmp".
The XX is usually a hex number depending on how many tmp files you
have in there. The file is also (99% of the time) deleted the second you
close the page it is linked to.
The good thing is that you can watch the video before it's fully
downloaded. A very good thing if you are on dial-up :)
Does anyone have a list of retro video's on YouTube? I know most can be
found by searching for the appropriate machine name, but not everyone
has decent tags with there videos :(
Regards,
Andrew B
aliensrcooluk at yahoo.co.uk
woodelf <bfranchuk at jetnet.ab.ca> wrote:
Right now I am trying to VIEW the %$@! You-Tube stuff. I hate
streaming
stuf on dial up. I don't think I will ever get more than the 1st few
minutes
of the UNIVAC stuff. Nothing like comparing almost 60 years of
computing
development.
> Cheers,
> Chuck
>