Paul
A friend and me (hi Steph :-) had the dot positions of the letter "A"
From somewhere as it was printed on the screen. What started like a "I'm
really bored, let's do something quick before the TV show starts to kill
time" went soon out of control. :-)
I think we both were not firm enough for Assembler, so wrote a Basic
program to search the whole memory for that pattern (the 8 bytes IIRC of
which every character's dot matrix was consisted of). It ran very slow
and I guess it took some hours to come to a result: no results.
It was already late in the evening and we had to go to school. At some
point I was so tired I saw no point in figuring out was our mistake was
right now so I went home.
I think he came late for school next day or even didn't come. Next time
we spoke he told me he didn't sleep that night, wanted to find out what's
wrong.
Well he couldn't. Our mistake was that the character rom is not visible
to the basic interpreter. You had to switch the bank, but then you would
have no basic rom and the C64 would crash. That we didn't know at that
point. And wasted precious hours of hour youth (instead of going to
school). :-)
Of course we missed that TV show (probably Magnum P.I.) also.
--
Andreas
My Commodore 64 classic game music page at
http://freenet-homepage.de/ankman/sid.html
Andreas Kohlbach wrote:
> dunric wrote on 19. June 2009:
> Our mistake was that the character rom is not visible
> to the basic interpreter. You had to switch the bank, but then you would
> have no basic rom and the C64 would crash.
<nitpicking>
That's not correct. You can switch in the CHARROM without removing BASIC
and KERNAL. You only have to disable the IRQ, as the IRQ handler expects
the I/O area to be visible. An NMI (CIA #2, RESTORE) would be
problematic, too, so disabling it would be a good idea, but in general,
it would even work without it.
</nitpicking>
Regards,
Spiro.
--
Spiro R. Trikaliotis http://opencbm.sf.net/
http://www.trikaliotis.net/ http://www.viceteam.org/
Getting an alternate binary-to-GCR converter for the 1571 drive to fit
into
768 bytes of spare drive RAM, *and* getting same to run at drive speed
so that the entire block can be written with no misses. I could write
floppies at a 5:1 interleave, if memory serves. (Couldn't go any
faster
because I still needed the 1571 rom routines for inter-block stuff.
What garbage that 1571 code was!) I had a fast floppy disk copier
that beat the pants off of anything else I've seen.
I thought about commercializing it, but that was just about the time
commodore bit the dust. Too bad.
Still, it was exciting making that accomplishment, especially at 13
years old and I don't think anyone else had ever done it at that
time. Now, I think a few years later I saw some other programs like
that pop up on BBSs and later on the internet.
I don't remember what year it was, but I downloaded a graphic display program
from Q-Link for the 80 column mode of the C128. The one I downloaded worked
on the 16 K flat 128. It not only did Doodle files but the C= files starting
with gg and 16 color .gif files. I think the author was Chris Smeets of ARC
fame.
--
Best regards,
Sam Gillett
Change is inevitable,
except from vending machines!
I was addicted to the game Neuromancer, and a friend and I were
playing this at the same time, trying to get through it. We would
share our discoveries each day and help each other out. He got through
the game the a couple of hours before I did. That was pretty cool.
Also, they used to sell Commodore computers in Sears and Service
Merchandise and we would go in there and create a small BASIC loop
program that would scroll obscenities down the screen when no one was
looking. :-)
I remember January 4, 1983. I had just gotten a copy of the 64
Programmer's Reference and was trying to do graphics. I couldn't
put the screen in Hi Res mode. I called Commodore and the guy there
wasn't sure how to do it either. The 64 was very new at the time.
We stayed on the phone for an hour and a half! Try getting that level
of support today. Finally he had to go. I started looking through an
old VIC-20 manual I had and, there was a POKE to put the screen in
Hi Res on that machine. I looked through the 64's manual again
and, nope, no mention of the POKE (The manual was revised a week later).
Finally I figured out the POKE for the 64 and played with it until about 4
am.
My wife finally yelled down for me to come to bed because she was sure
she'd be going into labor soon. I didn't believe her. About 6 am, sure
enough, she went into labor and I had to take her to the hospital.
Our first child, Sarah, was born at 11 am on January 5th.
(That's how I'm so sure of the date!)
Tom Lake
<SNIP>
>
>I was addicted to the game Neuromancer, and a friend and I were
>playing this at the same time, trying to get through it. We would
>share our discoveries each day and help each other out. He got through
>the game the a couple of hours before I did. That was pretty cool.
>
>Also, they used to sell Commodore computers in Sears and Service
>Merchandise and we would go in there and create a small BASIC loop
>program that would scroll obscenities down the screen when no one was
>looking. :-)
I used to do the same thing BUT I made the screen/border flash through
the 16 colors. Used to drive the sales ppl nuts..
Yes.. today that conversation would probably go like this:
TECH: (female with indian accent) Yes, thank you for calling Compaq,
my name is Sue Johnson how may I help you?
YOU: Yes, I'm having difficulty figuring out how to get my video card
in my Compaq into hi-res mode.
TECH: Yes sir, I understand you are having trouble getting your video
card into hi-res mode. Please stay with me and I will be glad to help
you with that.
30 seconds goes by.. tech looking over flow chart showing common
problems. doesn't see it listed, takes a guess.
TECH: Sorry you are having trouble with this sir, have you tried
rebooting your computer?
YOU: Ugh.. well, not really, it isn't that kind of problem. I want to
know what registers in the video card I need to change.
TECH: Oh, sorry, I'll be happy to help you with that. Can you hold
please?
(5 minutes goes by)
TECH: Thank you for holding, Mr.. (name mispronounced badly) So in
order to fix this problem, you will need to run the software restore
on your computer because you are probably infected with some kind of
virus. Is there anything else I can help you with today?
Yes.. today that conversation would probably go like this: