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Old C64 Myths

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The Jester

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Apr 21, 1992, 1:10:41 AM4/21/92
to
riv...@mdcbbs.com writes:


> First off, thanks to all who posted lore on the Sinclair machines. It
>was fun to read about. The machine (a ZX81) is officially the
>dog's computer until such time as I build it into a robot or something.
>Since I don't have any manuals, a lot of my playing around is random
>peeks and pokes into the system. This reminded me of a story
>that was floating around years ago about the first Commdore 64 machines.
>The rumor was that there was a location you were never supposed to
>reference with either a peek or a poke. Due to some design defect in the
>custom chips, accessing this location would permanently damage the computer.
>I don't have any reason to believe this story, but wondered if others
>had heard something like it.

There was a reference in the C= 64 reference manual that said that
no guarentee was provided for people who randomly changed values in the
ROM's for either software or hardware. I remember it was a letter to the
editor in COMPUTE!(tm) or some such. They of course said nonsense and
went into great detail about you couldnot destroy hardware from software
<manical laughter into the distance>. I don't have my manual handy
but, when I dif it out I will post the reference if you like.
Of course someone else could find it and post it....
--
\ / / / / /\ | Unexpected program termination has one saving grace -
\\/ \/\ /\ \/ \/_ | you can usually guess how much data may have been lost.
/ \/ / \ \/ \ | --Jennifer Bonnitcha (Australian "journalist")
g880...@cs.uow.edu.au

Steve Ansell

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Apr 21, 1992, 11:48:27 AM4/21/92
to
In article <1992Apr21.0...@cs.uow.edu.au> g880...@cs.uow.edu.au (The Jester) writes:
>
>There was a reference in the C= 64 reference manual that said that
>no guarentee was provided for people who randomly changed values in the
>ROM's for either software or hardware. I remember it was a letter to the
>editor in COMPUTE!(tm) or some such. They of course said nonsense and
>went into great detail about you couldnot destroy hardware from software
><manical laughter into the distance>. I don't have my manual handy
>but, when I dif it out I will post the reference if you like.
>Of course someone else could find it and post it....
>--

I don't have a C= 64 manual around (my good ol Commodore is long dead "sigh"),
but I do recall this being the case. In fact I remember that when I got my
computer there was a note or something to the effect that it was a "newer" C=
64 and that there was some defect in the originally released machine. I recall
a friend telling me (I never verified this) that the instruction was either:

POKE 0,1
or
POKE 1,0

He claimed to have done it on a computer in some retail store. On a related
thread someone recently told me that there is a way to "pop" the curcuit
breaker on the Amiga 500 monitor. The guy claimed to have written a program
that continually increased the frequency until the breaker was overloaded or
some such. The hardware was of course fine after turning the monitor off and
then on again.


--
-Steven T. Ansell
Unix Consultant
Computing Services U.C.D.

Andrew KUCHLING

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Apr 21, 1992, 11:57:30 AM4/21/92
to
In article <1992Apr17...@mdcbbs.com> riv...@mdcbbs.com writes:
>The rumor was that there was a location you were never supposed to
>reference with either a peek or a poke. Due to some design defect in the
>custom chips, accessing this location would permanently damage the computer.
>I don't have any reason to believe this story, but wondered if others
>had heard something like it.
>

I believe this applied only to the PETs. A certain POKE would cause an I/O
chip to go out of sync, and burn itself out after a while. The C64 didn't
have this problem as far as I know; the comments in the manual about the dangers
of random poking are to protect you from crashing the computer and losing your
program.

Other stuff: on my Vic-20, connecting two pins in the cartridge port would cause
the most amazing display. I think it caused a high-res display of some section
of memory which usually was a simple pattern, so you wound up with something
looking like a coloured view of the traces on an IC.

Also, the best C64 hack ever, IMHO, was published in the Transactor, by
Zamara and Sullivan. On the C64 you could switch out the BASIC and OS ROMs and
access RAM underneath them. This was used to patch BASIC frequently.
However, you could also switch out the RAM where the I/O registers were
accessed, and use ordinary RAM underneath. Z&S wrote a pop-up help utility
that hid under here, and ran in it, with some small subroutines (copied on
top of the stack !!!) that would switch I/O RAM in, and print a character or
get one from the disk.
Z&S even published the source code to all this. As a larval-stage hacker,
this was highly inspirational.

Andrew Kuchling
fn...@binkley.cs.mcgill.ca

Dave Schaumann

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Apr 21, 1992, 1:43:06 PM4/21/92
to
In article <12...@ucdavis.ucdavis.edu>, cccstevn@underdog (Steve Ansell) writes:
>I don't have a C= 64 manual around (my good ol Commodore is long dead "sigh"),
>but I do recall this being the case. In fact I remember that when I got my
>computer there was a note or something to the effect that it was a "newer" C=
>64 and that there was some defect in the originally released machine. I recall
>a friend telling me (I never verified this) that the instruction was either:
>
> POKE 0,1
>or
> POKE 1,0

On the C64, locations 0 and 1 controlled things like whether you saw ROM
or RAM when reading a particular location, as well as controlling where
video chips were positioned in memory.

Needless to say, stuffing random values in those locations (especially
from the command interpreter) is just about the fasted way to lock up
the machine. I'm not aware that you could physically damage the machine
this way, though.

--
Dave Schaumann da...@cs.arizona.edu

Aaron M. Renn

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Apr 21, 1992, 1:55:24 PM4/21/92
to
In article <12...@ucdavis.ucdavis.edu> cccs...@underdog.ucdavis.edu (Steve Ansell) writes:
>In article <1992Apr21.0...@cs.uow.edu.au> g880...@cs.uow.edu.au (The Jester) writes:
>>
>>There was a reference in the C= 64 reference manual that said that
>>no guarentee was provided for people who randomly changed values in the
>>ROM's for either software or hardware. I remember it was a letter to the
>>editor in COMPUTE!(tm) or some such. They of course said nonsense and
>>went into great detail about you couldnot destroy hardware from software
>><manical laughter into the distance>. I don't have my manual handy
>>but, when I dif it out I will post the reference if you like.
>>Of course someone else could find it and post it....
>>--
>
>I don't have a C= 64 manual around (my good ol Commodore is long dead "sigh"),
>but I do recall this being the case. In fact I remember that when I got my
>computer there was a note or something to the effect that it was a "newer" C=
>64 and that there was some defect in the originally released machine. I recall
>a friend telling me (I never verified this) that the instruction was either:
>
> POKE 0,1
>or
> POKE 1,0
>

Memory locations 0 and 1 on the 6510 chip used in the C= 64 were
hardware control registers that were used to, among other things,
control whether or not the BASIC and kernal ROM's were switched in at
high memory addresses and to manipulate the cassette device. I've used
them for many of these puposes and while indeed POKE-ing the wrong value
into them would lock your computer, I never encountered anything that
_permanently_ did anything to the hardware. Aaron.

------------------------------------------------------------------------
* Aaron M. Renn | Indiana University, Bloomington, IN *
* Internet: ar...@indiana.edu | NeXT: ar...@anasazi.ucs.indiana.edu *
* Bitnet: ar...@indiana.bitnet | UUCP: uunet!iuvax!bronze!arenn *
------------------------------------------------------------------------

Ronald van Loon

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Apr 21, 1992, 2:55:31 PM4/21/92
to

"In article <1992Apr21.0...@cs.uow.edu.au> g880...@cs.uow.edu.au (The Jester) writes:
"
"I don't have a C= 64 manual around (my good ol Commodore is long dead "sigh"),
"but I do recall this being the case. In fact I remember that when I got my
"computer there was a note or something to the effect that it was a "newer" C=
"64 and that there was some defect in the originally released machine. I recall
"a friend telling me (I never verified this) that the instruction was either:
"
" POKE 0,1

I tried not to reply - but by old C64 hormones were playing up again :-). I
don't think above stuff would work - locations 0 and 1 directed the 6510 data
direction and input/output respectively. Normally, 'poke 1,0' would turn the
C64 in 'all RAM' - 64K RAM mode. Of course - normally there was some sort of
operating systems in certain locations, so it was mega-crash time. Now, if
someone would poke 0,0 first (turn everything on output), then poke 1,0 did
nothing... location 1 is also heavily used when you want to utilize the RAM
underneath the ROM - ROM was located at $a000 - $bfff (BASIC) and $e000 -
$ffff (Kernel), but there was also real RAM underneath suitable for code, data
and the like. Nice additional feature of the Video hardware was, that it read
the RAM underneath the ROM without having to resort to nasty switching every
split 60th sec. I once remember - and this is real folklore folks :-) - to
have written a digi-player (yes, digital sound on a C64) that was able to keep
53K of digital data (about 8 seconds reasonable quality), 4K of sequencing
data - leaving a blasting 6K for the program itself! (The first 1K of RAM is
reserved for operating systems). There was even some code in screen memory now
and again....

those were the days....


"or
" POKE 1,0
"
"He claimed to have done it on a computer in some retail store. On a related
"thread someone recently told me that there is a way to "pop" the curcuit
"breaker on the Amiga 500 monitor. The guy claimed to have written a program
"that continually increased the frequency until the breaker was overloaded or
"some such. The hardware was of course fine after turning the monitor off and
"then on again.
"
"
"--
" -Steven T. Ansell
" Unix Consultant
" Computing Services U.C.D.
"

--
Ronald van Loon (rvl...@cv.ruu.nl) 3DCV Group, Utrecht, The Netherlands.

Insanity is not bad in itself as long as there is a system to it. (H.Liberg)
Healthy absurdism once in a while has never hurt anybody (me)

Norman St. John Polevaulter

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Apr 21, 1992, 4:41:35 PM4/21/92
to
> [Rumor: You can destroy a Commodore 64 with a certain POKE...]

Sounds like a distorted version of a TRUE story about the Commodore PET.
See, the PET had this funky built-in monitor, right? Well, the monitor
was controlled entirely by the computer, so with a certain POKE you
could speed up the frequency (or something) to such an extent that
the monitor would blow. Compute! magazine DID confirm this, by the way.

Sigh... I remember when Compute! was GOOD, and I looked forward to getting
those huge issues packed full of reviews and program listings and games
and articles about every computer under the sun. Ah, those were the days.

[Your blood pressure just went up.] Mark Sachs IS: mbs...@psuvm.psu.edu
DISCLAIMER: Penn State cares about my money, not my opinions.
"All my father wanted to do was make a toaster you could really set the
darkness on -- and you perverted his work into those horrible machines!"

Jesse Michael

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Apr 21, 1992, 11:45:12 PM4/21/92
to
In article <12...@ucdavis.ucdavis.edu> cccs...@underdog.ucdavis.edu (Steve Ansell) writes:
>He claimed to have done it on a computer in some retail store. On a related
>thread someone recently told me that there is a way to "pop" the curcuit
>breaker on the Amiga 500 monitor. The guy claimed to have written a program
>that continually increased the frequency until the breaker was overloaded or
>some such. The hardware was of course fine after turning the monitor off and
>then on again.
>

Well, there _are_ video beam position write registers in the custom chips so
this might be possible...

From Compute(!)'s `Mapping the Amiga':

Location Range: $DFF02A-$DFF02C
Video Beam Position Write

By writing to these registers, you can force the video beam to move to a
particular screen position. The Amiga continually increments this position--
faster than you could possibly update these registers--so it's impossible to
freeze the beam at any one location. These registers are used for hardware
testing purposes.
To the programmer, these registers serve no practical purpose. In fact,
writing to VHPOSW can cause software errors, since the Amiga relies on the
consistent and timely occurrence of horizontal and vertical blanks for such
chores as refreshing dynamic RAM. Changing the beam position disrupts these
events.

--
Only those who attempt the absurd can achieve the impossible.

Dave Brown

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Apr 22, 1992, 11:52:58 AM4/22/92
to
In article <1992Apr21.1...@cv.ruu.nl> rvl...@cv.ruu.nl (Ronald van Loon) writes:
>In <12...@ucdavis.ucdavis.edu> cccs...@underdog.ucdavis.edu (Steve Ansell) writes:
>
>"In article <1992Apr21.0...@cs.uow.edu.au> g880...@cs.uow.edu.au (The Jester) writes:
>"
>"I don't have a C= 64 manual around (my good ol Commodore is long dead "sigh"),
>"but I do recall this being the case. In fact I remember that when I got my
>"computer there was a note or something to the effect that it was a "newer" C=
>
>I tried not to reply - but by old C64 hormones were playing up again :-). I
>don't think above stuff would work - locations 0 and 1 directed the 6510 data
>direction and input/output respectively. Normally, 'poke 1,0' would turn the
>C64 in 'all RAM' - 64K RAM mode. Of course - normally there was some sort of
>operating systems in certain locations, so it was mega-crash time. Now, if
>someone would poke 0,0 first (turn everything on output), then poke 1,0 did
>nothing... location 1 is also heavily used when you want to utilize the RAM
>underneath the ROM - ROM was located at $a000 - $bfff (BASIC) and $e000 -
>$ffff (Kernel), but there was also real RAM underneath suitable for code, data
>and the like. Nice additional feature of the Video hardware was, that it read
>the RAM underneath the ROM without having to resort to nasty switching every
>split 60th sec. I once remember - and this is real folklore folks :-) - to
>have written a digi-player (yes, digital sound on a C64) that was able to keep
>53K of digital data (about 8 seconds reasonable quality), 4K of sequencing
>data - leaving a blasting 6K for the program itself! (The first 1K of RAM is
>reserved for operating systems). There was even some code in screen memory now
>and again....
>

Well, of _course_, everyone knows that if you're going
to switch out the ROM in the Commodore 64, you first copy
it to RAM, so that the computer doesn't head off into
never-never land the next time there's an interrupt--_then_
you start mucking around with what's there. If I remember
correctly, the code to do this (in BASIC) looked kind
of bizarre---FOR i=<addr> TO <addr>:POKE I,PEEK(I):NEXT. It
_looked_ pretty senseless, but it was actually doing
something...you could also switch out the ROM character
set this way to do evil things with it (it still
took up space, even when you moved the pointers to
the character set to point to a different place)...

BTW, the guy who accused me of being a Philistine...the
Spectrum was a pretty terrible computer compared to, say,
the Amstrad CPC machines or (using a computer from about
the same era) the Trash-80 Model I (_great_ machine. Shame it
looked so much like a black-and-white VT100), I'd rather
program a Spectum in machine code than a PC clone (who wouldn't!)
And _Jet Set Willy_ on the Spectrum is _the_ best video
game in existence (IMHO)...

Dave Brown
dagb...@descartes.waterloo.edu

James Hague

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Apr 22, 1992, 12:43:11 PM4/22/92
to
>In article <1992Apr17...@mdcbbs.com> riv...@mdcbbs.com writes:
>
>The rumor was that there was a location you were never supposed to
>reference with either a peek or a poke. Due to some design defect in the
>custom chips, accessing this location would permanently damage the computer.
>I don't have any reason to believe this story, but wondered if others
>had heard something like it.

This sort of rumor was around before the C-64. The Pet and Atari
400/800 supposedly had similar dangerous memory locations. On
the Pet, some people claimed to have gotten smoke to come out
of their computer. On the 800, the sound chip was supposed to
burn out if you set the combined volume levels of the four audio
channels higher than 32. I know that the latter is definitely
not true. The Pet thing has been debated forever; I don't think
it had ever been confirmed, which leads me to believe it was
also untrue.
--
James Hague
exu...@exu.ericsson.se

Nick Haines

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Apr 22, 1992, 2:02:01 PM4/22/92
to
In article <92112.164...@psuvm.psu.edu> Norman St. John Polevaulter <MBS...@psuvm.psu.edu> writes:

> [Rumor: You can destroy a Commodore 64 with a certain POKE...]

Sounds like a distorted version of a TRUE story about the Commodore PET.
See, the PET had this funky built-in monitor, right? Well, the monitor
was controlled entirely by the computer, so with a certain POKE you
could speed up the frequency (or something) to such an extent that
the monitor would blow. Compute! magazine DID confirm this, by the way.

Stuff Compute! magazine. _I_ confirmed it. Repeatedly. The sixth-form
college I went to had about 40 of these when I got there. And about 35
when I left. :-) You could get them to make sound by suitably
manipulating the video controller, too.

They didn't actually blow up. They just emitted a lot of smoke and
died.

Nick Haines nic...@cs.cmu.edu

John Davis

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Apr 22, 1992, 6:56:57 PM4/22/92
to
In article <1992Apr22.0...@agora.uucp>, j...@agora.uucp (Jesse Michael) writes:
> In article <12...@ucdavis.ucdavis.edu> cccs...@underdog.ucdavis.edu (Steve Ansell) writes:
>>He claimed to have done it on a computer in some retail store. On a related
>>thread someone recently told me that there is a way to "pop" the curcuit
>>breaker on the Amiga 500 monitor. The guy claimed to have written a program
>>that continually increased the frequency until the breaker was overloaded or
>>some such. The hardware was of course fine after turning the monitor off and
>>then on again.
>>
>
> Well, there _are_ video beam position write registers in the custom chips so
> this might be possible...

actually it's a lot easier if your amiga has the new ECS in it, as that
allows for more or less totally programmable video (sync position and length,
frame length etc). When it first became available I played around with it
quite a lot - taking the frame rate up to 65Hz etc. I never got my 1084
to shutdown (got some pretty weird displays though when I got the numbers
wrong), however a friends 1081 did shut down (doesn't actually pop a breaker
as such, the monitor simply looses sync and refuses to re-sync
until power cycled - no big deal, certainly not like all these doom-and-gloom
stories you see people putting about of the possibility of frying the monitor).

Actually the best I managed was a usable 64Hz mode - noticably reduced
interlace flicker (this was back in the bad old days before I used a VDE).
However I sent it across town for a friend to try out on his machine (which
had a new model 1084 monitor on it). He rang back saying he got _no_ display
at all - rather weird. We ended up using a scope and a freq counter to see what
was going on - I'd somehow forgotten to enable the h-sync, how
my own monitor ever managed to cope with that I'll never know...

--
-----------------------------------------------------------
| o John Davis - CHE...@csc.canterbury.ac.nz o |
| o (Depart)mental Programmer,Chemistry Department o |
| o University of Canterbury, Christchurch, New Zealand o |

Peter Joachim Unold

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Apr 22, 1992, 7:35:16 PM4/22/92
to
dagb...@descartes.waterloo.edu (Dave Brown) writes:
>looked so much like a black-and-white VT100), I'd rather
>program a Spectum in machine code than a PC clone (who wouldn't!)
>And _Jet Set Willy_ on the Spectrum is _the_ best video
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>game in existence (IMHO)...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

No doubt about that!! it was coded by a dude named Matthew Smith when
he was only 18years old. It was a kind of sequel to Manic Miner. It was
rumored that he made $150.000 on the game, and that Software Project tried
to cheat him... Anyway the label on the tape showed Jet-Set Willy bending
over a toilet. You could see 3 small letters on one of his boots. NCB i think.
It should be an abbreviation for National Coal Board or something.... That
game really showed how much power was hidden inside the zx-spectrum. Needless
to say that the C=64 conversion of the game, wasn't as good as the zx-spec.
version..(no flames - I'm a c=64 freak too).

- Peter Unold

Ethan Dicks

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Apr 23, 1992, 2:03:07 AM4/23/92
to
> This reminded me of a story
>that was floating around years ago about the first Commdore 64 machines.
>The rumor was that there was a location you were never supposed to
>reference with either a peek or a poke. Due to some design defect in the
>custom chips, accessing this location would permanently damage the computer.

This rumor is not true for the C-64. It is, however, possible to damage
an 80 column PET (as well as the monitor on a PC equipped with an original
IBM Mono board). The damage occurs by either setting the parameters of the
6845 CRT controller IC to some unacceptable value and driving the monitor
in a way in which it cannot handle or by setting the vertical retrace sense
line from input to output, causing the software to always belive that the
beam is in the vertical retrace area and not wait to refresh the screen
until the current frame is over. If the input is changed to an output,
the bit sense is always true, but the circuit was not designed to be driven
and some component is caught in the middle.

-ethan

--
Ethan Dicks ! Sponsored by the breakfast of Pennsic Veterans everywhere...
! "Beerios. They don't stay crisp in beer, but who cares?"

UUCP: n8emr!uncle!jcnpc!kumiss!e...@zaphod.mps.ohio-state.EDU

Calum F Benson CS90

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Apr 23, 1992, 4:24:59 AM4/23/92
to
In article <1992Apr22.1...@descartes.waterloo.edu> dagb...@descartes.waterloo.edu (Dave Brown) writes:
>
>BTW, the guy who accused me of being a Philistine...

That's me!

> the Spectrum was a pretty terrible computer compared to, say,


>the Amstrad CPC machines or (using a computer from about
>the same era) the Trash-80 Model I (_great_ machine. Shame it
>looked so much like a black-and-white VT100),

I can't really accept the comparison between the Amstrad and the Spectrum,
I'm afraid - the Speccy was on the market well before Mr. Sugar's effort.
Yes, the CPC was nice too - but somewhat expensive in comparison. And the
`avec-serif' character set was almost worse than Sinclair's, if that's
possible! About the only real competition I could see in the early days was
the Elan/Flan/Enterprise (64K and 4-channel stereo sound, I believe), but it
it took so long to get it into production the Spectrum and Commode 64 had
the market tied up by then.


>And _Jet Set Willy_ on the Spectrum is _the_ best video
>game in existence (IMHO)...
>

Have to disagree again! It was as buggy as hell - you can't see half
the things you're supposed to collect, some of them are unreachable anyway,
and then of course there's the legendary Attic bug. About the only thing that
can be said for it is that it introduced most of the Spectrum-owning
population to hacking games. Overall, I thought Manic Miner was much more
playable. Sorry.
What was everybody else's favourite Spectrum game from the good old days
(i.e. pre-film/arcade licences)? I was an Alchemist fan, myself ..


+---------------------------------------------+---------------------------+
|"When John Major announced that devolution | CALUM BENSON |
| for Scotland would mean divorcing two great | 3RD YEAR COMPUTER SCIENCE |
| nations, Scots everywhere were left asking | University of Strathclyde |
| which other great nation he meant." | Glasgow, Scotland |
+---------------------------------------------+---------------------------+
| cbe...@uk.ac.strath.cs AND cad...@uk.ac.strath.ccsun |
+-------------------------------------------------------------------------+

Lars Soltau

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Apr 23, 1992, 8:05:31 AM4/23/92
to
In article <1992Apr21.1...@cs.mcgill.ca> fn...@cs.mcgill.ca (Andrew KUCHLING) writes:

I believe this applied only to the PETs. A certain POKE would cause
an I/O chip to go out of sync, and burn itself out after a while.
The C64 didn't have this problem as far as I know; the comments in
the manual about the dangers of random poking are to protect you
from crashing the computer and losing your program.

Oh no, it is quite possible to fry a C64 via software, albeit the only
way I know requires a floppy connected to the IEC bus. The 1541, the
floppy disk drive for the C64, is a complete computer with 6502 CPU,
RAM and ROM itself and it is possible to download code into the floppy
RAM and have it executed by the floppy. (!) By first downloading a
piece of code to the floppy that turns the I/O chip on "all output"
and the signal lines on "lo", then turning the I/O chip on the C64
itself to "all output" and the signal lines to "hi", you can watch the
poor little C64 CIA trying to hold its lines to "hi" until it gets fried.
Lasts about a minute or two.
--
Lars Soltau bang: <insert ridiculously long path> BIX: -- no bucks --
smart: sp...@ncc1701.stgt.sub.org

Germany, Stuttgart-Zuffenhausen, where dreams come true: Heaven is 911!

I just hate it when Christians say atheists are void of morals. It just
makes me want to go get the chainsaw and take a quick trip down to the
local playground and... :-)
-- Mike Prather on alt.atheism
--
Lars Soltau bang: <insert ridiculously long path> BIX: -- no bucks --
smart: sp...@ncc1701.stgt.sub.org

Germany, Stuttgart-Zuffenhausen, where dreams come true: Heaven is 911!

Jay Ashworth

unread,
Apr 23, 1992, 12:04:00 PM4/23/92
to
Nick Haines, to All on Thursday April 23 1992:

NH> Stuff Compute! magazine. _I_ confirmed it. Repeatedly. The sixth-form
NH> college I went to had about 40 of these when I got there. And about 35
NH> when I left. :-) You could get them to make sound by suitably
NH> manipulating the video controller, too.

NH> They didn't actually blow up. They just emitted a lot of smoke and
NH> died.

This is indeed, as I thought, the same thing you could do with TRS-80 models
2 and (I think) 3 & 4. The Moto 6845 CRTC allows you to poke in the scanning
frequencies. Set them down too low, and your horizontal output circuit
overheats.

"Nothing you can do from the keyboard can caae any permanent physical harm to your computer." Yeah. Right.

Cheers,
-- jra
---------------------------------------------------------------------------
Jay R. Ashworth jra%ac...@tct.com
Ashworth & Associates Jay_Ashworth@{psycho.fidonet.org,
An Interdisciplinary Consultancy f160.n3603.z1.fidonet.org}
in Advanced Technolog +1_813_449_UNIX@Long_Lines.com

--
Internet: Jay.As...@f160.n3603.z1.FIDONET.ORG
UUCP: ...!uunet!myrddin!tct!psycho!160!Jay.Ashworth
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Mika Heiskanen

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Apr 23, 1992, 12:14:59 PM4/23/92
to

>>He claimed to have done it on a computer in some retail store. On a related
>>thread someone recently told me that there is a way to "pop" the curcuit
>>breaker on the Amiga 500 monitor. The guy claimed to have written a program
>>that continually increased the frequency until the breaker was overloaded or
>>some such. The hardware was of course fine after turning the monitor off and
>>then on again.

Ah, this reminds me of the days when I used to make demos on the good old
C64. In one called "Charlatan" I claimed that you can increase the clock
frequency of C64 with some 'undocumented' commands. I had a routine which
changed the screen colour 37 in one raster row to back this up. Naturally
it was done by other means (scrolling the bad line) but still I even got a
call from Holland from a guy who kept saying "It can't be possible". Funny
how he hang up when he realized it was just a joke... :)
--
--> mhei...@vipunen.hut.fi

Greg Goss

unread,
Apr 24, 1992, 10:18:48 AM4/24/92
to
> riv...@mdcbbs.com writes:
>
> that was floating around years ago about the first Commdore 64 machines.
> The rumor was that there was a location you were never supposed to
> reference with either a peek or a poke. Due to some design defect in the
> custom chips, accessing this location would permanently damage the computer.
> I don't have any reason to believe this story, but wondered if others
> had heard something like it.
>


It was possible to damage the video monitor on the MUCH earlier PET computers.
Is this what you're thinking of?

Didn't some of the 6502 chips (not the ones in CBM products, but the clone
chips that came from Rockwell) have a bad reaction to one of the undocumented
opcodes? I've heard many references to "CNB: Crash and Burn", that could burn
out the processor.

Could you be thinking of one of these?

.../greg

--
"say NO to four-line sigs" greg...@mindlink.bc.ca

a...@cruzio.santa-cruz.ca.us

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Apr 24, 1992, 2:46:26 PM4/24/92
to

What has always amazed me about the C64 is it's longetivity. I just talked to
my brother who is using my '83 C-64. It doesn't have any problems. Keyboard
and monitor are still both ok. The only thing that broke down was the 104i
(read: 1041) floppy drive, which fell down the stair a few years back when
I gave the thing to my brother. It is the ONLY pre-85 computer that I have
and which still works. _Very_ Good quality. I wish they would still make
computers that way.

Aki.

--
/ Phone: 408-662 9664 Fax: 662 9676 | "Aki" pronounced: Ah-Key. I know \
\ GENIE: A.KORHONEN Home: /dev/nul | what I'm doing most of the time. /

John Howard Osborn

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Apr 27, 1992, 3:13:12 PM4/27/92
to
In article <35...@cruzio.santa-cruz.ca.us> a...@cruzio.santa-cruz.ca.us writes:
>What has always amazed me about the C64 is it's longetivity. I just talked to
>my brother who is using my '83 C-64. It doesn't have any problems. Keyboard
>and monitor are still both ok. The only thing that broke down was the 104i
>(read: 1041) floppy drive, which fell down the stair a few years back when
>I gave the thing to my brother. It is the ONLY pre-85 computer that I have
>and which still works. _Very_ Good quality. I wish they would still make
>computers that way.


This completely amazes me. Completely. In 4 years or so, I went through
about 13 C64s. (C=64?) The power supplys seemed to be completely crap.
They would die and, usually, kill the computer as well. (That was how I
went through so many machines.) I don't even want to think about all the
times I had to realign the darn disk drives. Definately a VERY unreliable
machine. On the other hand, it did take me through highschool (writing
papers with EasyScript) and did teach me lots and lots about hacking and
modeming in general.

Amazingly, I do sort of miss playing with my Vic-20 and C64. If for nothing
else than the fact that my 64 ran the best videogame ever written: Jumpman.

-
-John H. Osborn
-osb...@cs.utexas.edu

Bill Marcum

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Apr 28, 1992, 5:36:09 AM4/28/92
to
In article <11...@mindlink.bc.ca> Greg...@mindlink.bc.ca (Greg Goss) writes:

Didn't some of the 6502 chips (not the ones in CBM products, but the clone
chips that came from Rockwell) have a bad reaction to one of the undocumented
opcodes? I've heard many references to "CNB: Crash and Burn", that could burn
out the processor.

Could you be thinking of one of these?

I read about this instruction in an old Byte magazine (Actually, it was new
when I read it). The crash and burn instruction didn't permanently harm the
microprocessor, it just caused the address bus to cycle through all 65536
addresses continuously, ignoring IRQ, NMI, and even RESET. You would have
to shut off the power to return things to normal.

Oke S

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Apr 28, 1992, 8:12:15 AM4/28/92
to
In article <thjo8...@cs.utexas.edu> osb...@cs.utexas.edu (John Howard Osborn) writes:

>This completely amazes me. Completely. In 4 years or so, I went through
>about 13 C64s. (C=64?) The power supplys seemed to be completely crap.
>They would die and, usually, kill the computer as well. (That was how I
>went through so many machines.) I don't even want to think about all the
>times I had to realign the darn disk drives. Definately a VERY unreliable
>machine. On the other hand, it did take me through highschool (writing
>papers with EasyScript) and did teach me lots and lots about hacking and
>modeming in general.

I had a 64 for about 3 years; I got it second-hand. It had one of the
original style power supplies, and I never had a single problem with it.
On the other hand, the VIC chip suddenly died about 5 days after I bought
the machine. :-(

>Amazingly, I do sort of miss playing with my Vic-20 and C64. If for nothing
>else than the fact that my 64 ran the best videogame ever written: Jumpman.

Sorry, but I have to disagree here; the best game was Archon.

--
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# # # # # # # # ## #
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# # # # # # # ##
#### ### # # #### # #
Live long and prosper.

Mark Stephens (MSc Stephen Furber)

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Apr 28, 1992, 10:11:17 AM4/28/92
to
Jay.As...@f160.n3603.z1.FIDONET.ORG (Jay Ashworth) writes:

>Nick Haines, to All on Thursday April 23 1992:

> NH> They didn't actually blow up. They just emitted a lot of smoke and
> NH> died.

>This is indeed, as I thought, the same thing you could do with TRS-80 models
>2 and (I think) 3 & 4. The Moto 6845 CRTC allows you to poke in the scanning
>frequencies. Set them down too low, and your horizontal output circuit
>overheats.


I believe that some designs of monitor rely on a horizontal sync pulse
starting a flyback in otherwise the HV supply just keeps on ramping up.

Marks. ma...@cs.man.ac.uk

Karthik P. Sheka

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Apr 28, 1992, 1:26:16 PM4/28/92
to
In article <thjo8...@cs.utexas.edu> osb...@cs.utexas.edu (John Howard Osborn) writes:

I went through a few power supply packs before I guessed at what was wrong.
Apparently, those things are not powerful enough to be connected to a power
line continuously. Solution? I just hooked my C=64, disk drive, monitor,
and radio onto a power strip, and kept the strip off whenever I wasn't
using it. Since then, I've never had a problem. (I burnt out three power
supplies in six months, before I used the power strip, and haven't burnt
out a single one in the last 6 years :-)... I wouldn't call that
conclusive, but it works for me!

ObHack: My first hack was on a C=64. I had to write a program that took a
formula from the user and graph it on the screen from o to 360 degrees on
the x axis and -2 to 2 on the y axis. I had the user input the formula as
a string, then printed it to the to of the screen, preceded by a line
number, flooded the keyboard buffer, and then stopped the program. The
keystrokes stored in the keyboard buffer would then add the line to my
program and start up the program again, from a predesignated point. My
teacher was amazed that I was able to compute extremely complex formulae
without haveing to parse the input :-)

technopagan priest

unread,
Apr 29, 1992, 3:35:36 AM4/29/92
to
In article <SPACE.92A...@ncc1701.stgt.sub.org> sp...@ncc1701.stgt.sub.org (Lars Soltau) writes:
>In article <1992Apr21.1...@cs.mcgill.ca> fn...@cs.mcgill.ca (Andrew KUCHLING) writes:
>
> I believe this applied only to the PETs. A certain POKE would cause
> an I/O chip to go out of sync, and burn itself out after a while.

I rather doubt this...the only hardware damage program I ever saw
on the PET was a program which rapidly clicked a relay inside the
casette drive (which was internal to some PETs, but fairly standard
accessories to all others). If you let it run for a few hours, you
might get lucky and toast the relay.

I'm sorry I let go of my PET...I miss it! A brother in my fraternity
bought two of them two or three years ago, only they tended to crash
alot due to aging memory chips.

-Tom


Edward Yagi

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Apr 29, 1992, 7:40:54 AM4/29/92
to
osb...@cs.utexas.edu (John Howard Osborn) writes:
> a...@cruzio.santa-cruz.ca.us writes:
>>I gave the thing to my brother. It is the ONLY pre-85 computer that I have
>>and which still works. _Very_ Good quality. I wish they would still make
>>computers that way.

Hear! HEar! It was a neat machine! I loved it to death.. would have
probably stuck to it till this day but a burgler broke into our house
a coupla years ago and STOLE my C=64.. :( lost lots of 'first' programs
I created on it.. 10 print 'hello' 20 goto 10..


>
> On the other hand, it did take me through highschool (writing
>papers with EasyScript) and did teach me lots and lots about hacking and
>modeming in general.

EASYSCRIPT! augh! I spent many-o-hours on that neato sceato WP.. there
was an 'Easter Egg' within that, in which you press a series of Control
sequences? and it plays this really cool tune, utilizing the incredible
3 voices C=64 had.. (taking notes IBM?)

>
>Amazingly, I do sort of miss playing with my Vic-20 and C64. If for nothing
>else than the fact that my 64 ran the best videogame ever written: Jumpman.
>

Hey! If you dont know, theres a incredibly, I mean INCREDIBLY well done
clone made for the IBM, I think its called numjum.zip or sumthin to
that effect, speaking as a former Jumpman-Addict for the 64, I have to
say the clone shareware is true to its form, the only drawback is the
sound effects (still taking notes IBM?) If you cant find it, Ill email
you a uudecoded copy..

James Hague

unread,
Apr 29, 1992, 10:52:33 AM4/29/92
to
>What has always amazed me about the C64 is it's longetivity. I just talked to
>my brother who is using my '83 C-64. It doesn't have any problems. Keyboard
>and monitor are still both ok.

Sitting in my parents' living room is a 1982 Atari 800 which is
still kicking. The 810 disk drives died repeatedly, but the 1050
has been going since 1985 without alignment or cleaning. The
only thing wrong with the computer is the spring on the cartridge
door gave out around 1988 (remember the door?).

--
James Hague
exu...@exu.ericsson.se

Jukka Marin

unread,
Apr 30, 1992, 7:11:32 AM4/30/92
to
In article <1992Apr28.1...@cs.columbia.edu> kar...@cs.columbia.edu (Karthik P. Sheka) writes:

>I went through a few power supply packs before I guessed at what was wrong.
>Apparently, those things are not powerful enough to be connected to a power
>line continuously. Solution? I just hooked my C=64, disk drive, monitor,
>and radio onto a power strip, and kept the strip off whenever I wasn't
>using it. Since then, I've never had a problem.

I had my good old 64 on 24 hours a day and I never had any problems with
it (well, then I decided the 64 was running too hot and cut a hole to the
left side of the box and put a fan there.. :)

Later, I built an EPROM burner within the 64 box. I was (and am) able to
burn 2K..64K EPROMs and the paged 4*16K ones as well. I also added
support for EEPROMs and the so-called Zero Power RAMs made by Dallas.
So, my 64 has about twice as many IC's as it used to.. All powered from
the original power supply .. still no problems! :-) BTW, my 64 is an
early '83 model with 64k*1 DRAMs.

>ObHack: My first hack was on a C=64. I had to write a program that took a
>formula from the user and graph it on the screen from o to 360 degrees on
>the x axis and -2 to 2 on the y axis. I had the user input the formula as
>a string, then printed it to the to of the screen, preceded by a line
>number, flooded the keyboard buffer, and then stopped the program. The
>keystrokes stored in the keyboard buffer would then add the line to my
>program and start up the program again, from a predesignated point. My
>teacher was amazed that I was able to compute extremely complex formulae
>without haveing to parse the input :-)

We used the same method in our "Andehire" interpreter (written partly in
Basic, partly in machine language (assembler? we had no assembler that
time, we did everything by hand)). Andehire was _very_ slow but it
contained some powerful commands (like one to display a clock in the upper
right corner of screen or the semi-graphic commands etc.). It took
about 15 minutes to save Andehire on tape...

Jukka Marin

--

| Mail: Jukka Marin | E-Mail: jmarin@messi@uku.fi |
| Metsurintie 17 B 8 | There's God above computers - |
| 70150 Kuopio, FINLAND | Love beyond the hate |

Eliot Shimoff

unread,
Apr 30, 1992, 9:56:55 AM4/30/92
to
>
>Sitting in my parents' living room is a 1982 Atari 800 which is
>still kicking. The 810 disk drives died repeatedly, but the 1050
>has been going since 1985 without alignment or cleaning. The
>only thing wrong with the computer is the spring on the cartridge
>door gave out around 1988 (remember the door?).
>
>--
>James Hague
>exu...@exu.ericsson.se

BIG DEAL. Sitting in my lab is a circa 1979 Apple II that still
runs -- and that has been running 3-4 hrs per day, 7 days a
week, for about two-thirds of its life.

This, folks, is a vintage Apple II. It came with the red-covered
mimeographed manual, 16 k memory (the standard then as 4k; we
bought the very best), on-board integer BASIC, a RESET key in
the upper right corner that didn't require the CTRL key (easy
to blow yourself out of the water with a wanderig pinkey finger),
etc. No disk drives; this was before Apple had disk drives
available.


--
Eliot Shimoff | n n n
shi...@umbc3.umbc.edu | X + Y = Z . Easy to prove no solutions
Ashamnu, bagadnu, gazalnu ... | for n greater than 2. Darn. Can't fit
Better luck next year! | it into this little .sig file. Oh well.

John Howard Osborn

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Apr 30, 1992, 12:54:20 PM4/30/92
to

The technique of filling the keyboard buffer and stopping your program
was pretty common. The advanced version took advantage of the full
screen editing system. First you'd clear the screen. Then, you'd
position commands so that there was just enough space for results
to be displayed after each command. Something like:

(top of screen)


command

(
( results of command )
(

next_command

Then you'd position the cursor BACK to the top of the screen,
fill the keyboard buffer with <returns>, and END. You had to
do it this way because you only has space in the buffer for about
10 characters. Using this hack, you could write self modifying
basic or load and run other programs or whatever.

I also had only of the early C=64s, specifically one with "snow."
There was a problem with the video circuitry such that if the
screen displayed certain colors, you'd get this awful interference
pattern whenever you wrote to video. Ick.

Before the C=64, though, I really enjoyed my VIC-20. (I wish I could
remember what VIC stood for.) Cartridge games were really popular
for VIC computers, as were memory expansion cards. There were four,
4k, locations for expansion memory. At startup the system would check
for a program at the "highest" of these four memory areas and, if found,
would execute it. Cartridges would place the program, in rom, in this
location and so they would start automatically at powerup.

We discovered, though, that you could jam a game cartridge into a slot
while the system was powered up. On those times when the computer didn't
instantly freak, you could then run a "machine language monitor"
(usually tinymon) to dump the contents of the cartidge ROMs to tape.

Now what you could do is plug in a RAM card, configured to be at that
address, load the image from tape into the RAM, and execute a soft-reset.

Ta-da! A successfully copied game cartridge. (I was AMAZED the first
time I saw this.) Later, cartridge makers got smart. They put in
code that wrote all over the cartridge memory at the beginning of
execution. If it was ROM, nothing got written and the game still worked.
If it was RAM (and it would only be RAM if it was a copy) the game would
crash. We then got smarter and put a toggle switch on the "write" line
of the memory card. You could load the image, turn off writes, and go.

We did all this strictly for backup purposes, however. :)

mar...@vax.oxford.ac.uk

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May 1, 1992, 2:18:05 PM5/1/92
to
In article <tp8ns...@cs.utexas.edu>, osb...@cs.utexas.edu (John Howard Osborn) writes:
>
> The technique of filling the keyboard buffer and stopping your program
> was pretty common. The advanced version took advantage of the full
> screen editing system. First you'd clear the screen. Then, you'd
> position commands so that there was just enough space for results
> to be displayed after each command. Something like:
>
Whatn't there a SYS call for this kind of thing, a hook into the basic
interpreter that evaluated an expression. I think the only problem was
that it did not deal with systax errors very well.

Mika Heiskanen

unread,
May 1, 1992, 1:16:23 PM5/1/92
to
In article <1992Apr30....@luotsi.uku.fi> jma...@messi.uku.fi (Jukka Marin) writes:

>>ObHack: My first hack was on a C=64. I had to write a program that took a
>>formula from the user and graph it on the screen from o to 360 degrees on
>>the x axis and -2 to 2 on the y axis. I had the user input the formula as
>>a string, then printed it to the to of the screen, preceded by a line
>>number, flooded the keyboard buffer, and then stopped the program. The
>>keystrokes stored in the keyboard buffer would then add the line to my
>>program and start up the program again, from a predesignated point. My
>>teacher was amazed that I was able to compute extremely complex formulae
>>without haveing to parse the input :-)
>
> We used the same method in our "Andehire" interpreter (written partly in
> Basic, partly in machine language (assembler? we had no assembler that
> time, we did everything by hand)). Andehire was _very_ slow but it
> contained some powerful commands (like one to display a clock in the upper
> right corner of screen or the semi-graphic commands etc.). It took
> about 15 minutes to save Andehire on tape...

Well, I did it in machine language. Just read the input, placed some
pointers to the input and called an interpreter routine to define it as a
function (basic command DEFFN, or something like it).

Just a couple of pokes...
--
--> mhei...@vipunen.hut.fi

"No screaming while the bus is in motion.." - Freddie Kruger

l...@polari.com

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May 2, 1992, 12:31:43 PM5/2/92
to
In article <tp8ns...@cs.utexas.edu> osb...@cs.utexas.edu (John Howard Osborn) writes:
>remember what VIC stood for.)

It stood for "Video Interface Chip," the breakthrought (at that time) chip
that contolled the computer's excellent video. It went on to power the
C=64 and 128's video as well, I beleive.

--
------- ======= ------- ======= ------- ======= ------- ======= ------- =======
uunet!polari!lsh -- l...@polari.com
Lee Hauser
If I pay for access, I don't have to disclaim ANYTHING!

Ben Scott

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May 2, 1992, 6:08:37 PM5/2/92
to
>What has always amazed me about the C64 is it's longetivity. I just talked to
>my brother who is using my '83 C-64. It doesn't have any problems. Keyboard
[...]

>and which still works. _Very_ Good quality. I wish they would still make
>computers that way.

But they do... last I heard (reliably, anyhow), Commodore sold nearly
800,000 units of the C-64 last fiscal year (!).

I guess it's mostly because it's still a damn good game machine, better than
the Nintendoid, and some realize this. At any rate, there are more C-64s
out there than any other single model of machine except the Nintendo (so far
as I know; the MS-DOS world being made up of hundreds of different makes and
models).

I got one... I use it to play M.U.L.E. still.

. <<<<Infinite K>>>>

--
|Ben Scott, professional goof-off and consultant at The Raster Image, Denver|
|Internet bsc...@nyx.cs.du.edu, or call the Arvada 68K BBS at (303)424-6208.|
|"He really DOES look like Max Headroom!"\| The Raster Image IS responsible |
|"No, actually HE looks like ME."-E.Carter|\for everything I say! | *Amiga* |

Jesper Lauridsen

unread,
May 3, 1992, 11:42:25 AM5/3/92
to
bsc...@isis.cs.du.edu (Ben Scott) writes:

>But they do... last I heard (reliably, anyhow), Commodore sold nearly
>800,000 units of the C-64 last fiscal year (!).

>I guess it's mostly because it's still a damn good game machine, better than
>the Nintendoid, and some realize this.

Have you seen the 64's sold these days? They have totally ruined the
design of it, and givin it the ugliest keyboard ever seen on something
not made by HP.

>I got one... I use it to play M.U.L.E. still.

I use mine for International Soccer and Alternate Reality.
--
I have things to do and News to read

Matthew Dustin Morgan

unread,
May 3, 1992, 8:20:12 PM5/3/92
to
l...@polari.com writes:
> It stood for "Video Interface Chip," the breakthrought (at that time) chip
> that contolled the computer's excellent video. It went on to power the
> C=64 and 128's video as well, I beleive.

Actually, an entirely new version of the VIC chip was used in the 64. It was
called, appropriately enough, the VIC-II. It had far greater resolution and
more capabilities than the original VIC (e.g. sprites, 16 colors, etc.).

The 128 has two video chips: one is a slightly modified VIC-II (I can't
remember the difference - it's really minor), and the other is an entirely new
chip used for an 80-column display.

On another note, it seems strange to think that the 6510 microprocessor in the
64 ran at 1 MHz... and the 128's 8502 was switchable between 1 and 2 MHz.
It seems incredibly slow compared to today's machines, but those computers
did their job well.

- Matt

--
-- Matt Morgan, Idahoan number 3 - mm...@rice.edu - Rice U. - Houston, Texas --
%***%%*%%*%*%%*%%**%**%*%%*%*%*%*%*%**%%%*%**%*%*%*%**%*%*%%*%*%*%%%*%%*%*%%*%%
"Now if Michael Jordan does a reverse slam dunk, is that a moral act?"
- Rice University professor (Huma 102)

Peter da Silva

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May 3, 1992, 8:21:34 PM5/3/92
to
In article <1992May2.2...@mnemosyne.cs.du.edu> bsc...@isis.cs.du.edu (Ben Scott) writes:
>But they do... last I heard (reliably, anyhow), Commodore sold nearly
>800,000 units of the C-64 last fiscal year (!).

At prices of up to $300 a pop. Why someone would pay $300 for a C=64 when
you can get an Amiga 500 for $400, is completely beyond me. Even brand
loyalty doesn't explain this level of cluelessness.
--
%!Peter da Silva, Taronga Park BBS. +1 713 568 0480/1032. `-_-'
% Have you hugged your wolf today? 'U`
systemdict /sig_virus known { eexec } if
0931789ABA04700000093759014FEEDFACE514783DEADBEEF59FFFF579837FFFF7315988971

Richard Griffith

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May 3, 1992, 9:46:36 PM5/3/92
to
In <1992May4.0...@rice.edu> mm...@ruf.rice.edu (Matthew Dustin Morgan) writes:

>l...@polari.com writes:
>> It stood for "Video Interface Chip," the breakthrought (at that time) chip
>> that contolled the computer's excellent video. It went on to power the
>> C=64 and 128's video as well, I beleive.

>Actually, an entirely new version of the VIC chip was used in the 64. It was
>called, appropriately enough, the VIC-II. It had far greater resolution and
>more capabilities than the original VIC (e.g. sprites, 16 colors, etc.).

>The 128 has two video chips: one is a slightly modified VIC-II (I can't
>remember the difference - it's really minor), and the other is an entirely new
>chip used for an 80-column display.

>On another note, it seems strange to think that the 6510 microprocessor in the
>64 ran at 1 MHz... and the 128's 8502 was switchable between 1 and 2 MHz.
>It seems incredibly slow compared to today's machines, but those computers
>did their job well.

``Design case history: the Commodore 64''
IEEE Spectrum Volume 22 #3, March 1985, page 48
Abstract: The `worlds greatest' video-game chips became the basis for the
worlds most popular personal computer.

The article includes excerpts from interviews with the designers of both
the VIC II and the SID. The NTSC color timing is discussed as well as the
screen video timing.

Screens from Ghostbusters(activision), Summer Games(Epyx) and Mission
Impossible(Epyx) are included.

Pictures of two different revisions of the main board are given
(automatic parts placement and manual parts placement).

Design decisions are discussed.

A very interesting article and must have for anyone who still owns and
adores a C64.

--
The summer league will start as soon as the snow melts.| Canadian weather is
Meanwhile we are playing on the snow.| wonderful, and we get so much of it.

Phillips C J

unread,
May 3, 1992, 11:21:42 PM5/3/92
to
rors...@daimi.aau.dk (Jesper Lauridsen) writes:

>bsc...@isis.cs.du.edu (Ben Scott) writes:

>>But they do... last I heard (reliably, anyhow), Commodore sold nearly
>>800,000 units of the C-64 last fiscal year (!).

>>I guess it's mostly because it's still a damn good game machine, better than
>>the Nintendoid, and some realize this.

Too right!

>Have you seen the 64's sold these days? They have totally ruined the
>design of it, and givin it the ugliest keyboard ever seen on something
>not made by HP.

Nonono! Much improved! No longer squat, dingy and brown, but cream and
slimline! (and much saner to type on than the PC horror I am stuck with
at the moment, for lack of a c64 modem :)

>>I got one... I use it to play M.U.L.E. still.

>I use mine for International Soccer and Alternate Reality.

I use mine for playing multifarious shootemups (armalyte forever!) and platform
games (Turrican! Great on Amiga, Stupendous on c64!) and writing the
revolutionary shootemup that will sweep the world, if only the release date
would arrive sometime :)


--
Christopher Jam __________________________________________________
'Another day, another try. But remember, SHOOT OR DIE!' -turrican
phil...@swanee.ee.uwa.oz.au c64 forever!!!!
------------------------------------------------------------------

Mauve Marauder

unread,
May 3, 1992, 11:57:37 PM5/3/92
to
In article <thjo8...@cs.utexas.edu>, osb...@cs.utexas.edu (John Howard Osborn) writes:
>
> This completely amazes me. Completely. In 4 years or so, I went through
> about 13 C64s. (C=64?) The power supplys seemed to be completely crap.
> They would die and, usually, kill the computer as well. (That was how I
> went through so many machines.) I don't even want to think about all the
> times I had to realign the darn disk drives. Definately a VERY unreliable
> machine. On the other hand, it did take me through highschool (writing
> papers with EasyScript) and did teach me lots and lots about hacking and
> modeming in general.
>
> Amazingly, I do sort of miss playing with my Vic-20 and C64. If for nothing
> else than the fact that my 64 ran the best videogame ever written: Jumpman.
>
For those interested, you can find a commodore 64 emmulator at
ATHENE.UNI-PADERBON.EDU. The sites in germany, and the program must be running
in herculese graphics card or emulation of it. You cant run the software, but
you can at least hack a little.
-----------------------------------------------------------------------------
I. Charles Barilleaux III occasionally know at Miami Univ
CBARI...@MIAVX1.ACS.MUOHIO.EDU as the Mauve Marauder

"Mr. Barilleaux, This is a good idea for a piece and sensible suggestion. You
write clearly and to the point. Your spelling could stand a bit of attention."
-Professor Jacobs (political science), on my latest paper. It is the
story of my life.

Ronald van Loon

unread,
May 4, 1992, 3:24:29 AM5/4/92
to
In <1992May1.1...@vax.oxford.ac.uk> mar...@vax.oxford.ac.uk writes:

sys $c000,<expression>

$c000: jsr $e200 ; skip , in basic program evaluate expression, leave result
in X-reg.


--
Ronald van Loon (rvl...@cv.ruu.nl) 3DCV Group, Utrecht, The Netherlands.

Insanity is not bad in itself as long as there is a system to it. (H.Liberg)
Healthy absurdism once in a while has never hurt anybody (me)

Brett G Person

unread,
May 4, 1992, 5:29:42 AM5/4/92
to
In article <1992Apr29.1...@exu.ericsson.se> exu...@exu.ericsson.se (James Hague) writes:
>In article <35...@cruzio.santa-cruz.ca.us> a...@cruzio.santa-cruz.ca.us writes:
>>
>Sitting in my parents' living room is a 1982 Atari 800 which is
>still kicking. The 810 disk drives died repeatedly, but the 1050
>has been going since 1985 without alignment or cleaning.

My faithfull 800 - ought in 1983, still works like a charm. So does
the 810 disk drive - bought in 1983 also.


Only problem I ever had with it: Space bar went out once ( thhanks
Atari for picking the SPace Bar for the Smart Bomb command in
Defender. You only had about 50 other choices of keys.)

Oh, and Dig Dug never did work right. I retruned it to the store
twice, and each cart would mysteriously crash occasionally. At
random points during the game. Never did figure that one out.

--
Brett G. Person
North Dakota State University
uunet!plains!person | per...@plains.bitnet | per...@plains.nodak.edu
If I have a chip on my shoulder, I sure hope it isn't a damned Intel

The Jester

unread,
May 4, 1992, 6:03:07 AM5/4/92
to
rvl...@cv.ruu.nl (Ronald van Loon) writes:

>In <1992May1.1...@vax.oxford.ac.uk> mar...@vax.oxford.ac.uk writes:

>| "In article <tp8ns...@cs.utexas.edu>, osb...@cs.utexas.edu (John Howard Osborn) writes:
>| ">
>| "> The technique of filling the keyboard buffer and stopping your program
>| "> was pretty common. The advanced version took advantage of the full
>| "> screen editing system. First you'd clear the screen. Then, you'd
>| "> position commands so that there was just enough space for results
>| "> to be displayed after each command. Something like:
>| ">
>| "Whatn't there a SYS call for this kind of thing, a hook into the basic
>| "interpreter that evaluated an expression. I think the only problem was
>| "that it did not deal with systax errors very well.

>sys $c000,<expression>

>$c000: jsr $e200 ; skip , in basic program evaluate expression, leave result
> in X-reg.

I don't think this is the correct address for this maybe down in $a000-$bfff
somewhere. $c000-$cfff was a 4k user ram area.


>--
>Ronald van Loon (rvl...@cv.ruu.nl) 3DCV Group, Utrecht, The Netherlands.

>Insanity is not bad in itself as long as there is a system to it. (H.Liberg)
>Healthy absurdism once in a while has never hurt anybody (me)

--
\ / / / / /\ | Unexpected program termination has one saving grace -
\\/ \/\ /\ \/ \/_ | you can usually guess how much data may have been lost.
/ \/ / \ \/ \ | --Jennifer Bonnitcha (Australian "journalist")
g880...@cs.uow.edu.au

Barry McConnell

unread,
May 4, 1992, 8:38:15 AM5/4/92
to
In <BG5...@taronga.com> pe...@taronga.com (Peter da Silva) writes:

>At prices of up to $300 a pop. Why someone would pay $300 for a C=64 when
>you can get an Amiga 500 for $400, is completely beyond me. Even brand
>loyalty doesn't explain this level of cluelessness.

You guys have a wierd pricing structure. Over here (Ireland), the Amiga 500+
is 500 pounds, and the C64 is something like 150-250 pounds. There's a BIG
difference in price...

>%!Peter da Silva, Taronga Park BBS. +1 713 568 0480/1032. `-_-'

Barry.

Lamar Owen

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May 4, 1992, 12:08:40 PM5/4/92
to
RE: 1979 Apple II.

I still have a serial number 00002 TRS-80 with 16K (again, the very
best) made in 1977. Works like a charm.

Anybody need TRS-80 stuff :-)...?

Lamar

AES...@psuvm.psu.edu

unread,
May 7, 1992, 2:16:11 AM5/7/92
to
In article <rjg.704943996@guinan>, r...@doe.carleton.ca (Richard Griffith) says:

>In <1992May4.0...@rice.edu> mm...@ruf.rice.edu (Matthew Dustin Morgan)
>writes:

>``Design case history: the Commodore 64''


>IEEE Spectrum Volume 22 #3, March 1985, page 48
>Abstract: The `worlds greatest' video-game chips became the basis for the
>worlds most popular personal computer.

>A very interesting article and must have for anyone who still owns and
>adores a C64.

Yes indeed!! Required reading for all C64 freaks (and hackers in
general). I don't know why Spectrum doesn't publish such hot
stuff anymore....

Paul Wallich

unread,
May 7, 1992, 5:33:56 PM5/7/92
to
In <92128.021...@psuvm.psu.edu> <AES...@psuvm.psu.edu> writes:

Because a) they have no ad pages
b) real engineers consider journalism unseemly
c) most of the folks who wrote for them have gotten real lives.

paul

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