
The MAD Computer Program - pplonski86
https://meatfighter.com/mad/
======
chris_overseas
Ah good times, I remember spending countless hours typing in source code like
this. At one point I also submitted the source for a couple of games I'd
written to a computer magazine when I was younger, and was delighted to get
one of them published. My address was included; if people sent me a $5 note
and a 5.25" floppy I'd return their disk containing a copy of the game plus a
couple of other "bonus" apps I'd written. I think I sold maybe 4-5 copies this
way and was pretty pleased with myself at the time!

I do recall having to send a disk back and forth a few times to one customer
because I'd reformatted his disk to double-sided (360k) but he only had a
single-sided drive[0]. After he tried and failed to read it, I spoke to him on
the phone, figured out the problem and asked him to return it. I reformatted
the disk back to single-sided (180k) so he could try again. That didn't work
either since it turned out the single sided drive only supported 160k rather
than 180k, which necessitated yet another round trip of his disk through the
postal system.

[0] I'd been using a Sanyo MBC-555-2, he had a Sanyo MBC-550.

~~~
benj111
Do you mean double sided or double density?

I distinctly recall having to rotate discs on my BBC, and seems strange to
needlessly break backwards compatibility.

~~~
chris_overseas
His drive was single-sided double-density, giving 160k storage. The ones I was
using were double-sided double-density, providing 360k of storage. I have no
idea why the single sided drive had a bit less than half the storage of the
double sided one though.

There were two "hacks" available with single vs double sided drives and disks.
5.25" floppies had a small notch in the side that, if you covered it with a
sticker, meant the drive treated it as read-only. By cutting an equivalent
notch in the opposite side of a disk to make it appear writable it was
possible to flip it over 180° and use both sides of a double-sided disk in a
single-sided drive. Conversely, disks that were rated as single-sided (and
hence cheaper) could generally still be used successfully in a double-sided
drive, though it wasn't recommended to store anything too important that way
because the failure/problem rate was noticeably higher. My guess is that the
single sided disks were binned as such due to them failing tests on one of the
sides during manufacturing.

~~~
benj111
Ah I see, so he had sent you a single sided disc then, that makes sense.

------
tyingq
Quick translation to javascript:
[https://jsbin.com/qipapokova/1/edit?js,output](https://jsbin.com/qipapokova/1/edit?js,output)

(Note I flipped it with css, too lazy to fix in js :)

Edit: Perhaps more historically accurate if you can watch it draw:
[https://jsbin.com/veniwodidi/1/edit?js,output](https://jsbin.com/veniwodidi/1/edit?js,output)

~~~
gnulinux
> Perhaps more historically accurate if you can watch it draw

Were computers really that slow back then or is that effect exaggerated for
nostalgia? Really hard to imagine computers that slow for us young generation.

~~~
tyingq
If anything, my simulation is being generous, at least for the C64:
[https://www.youtube.com/watch?v=k4h9a2QGdQM](https://www.youtube.com/watch?v=k4h9a2QGdQM)

That is, drawing from BASIC though. Games weren't saddled with that, so they
drew faster.

A comprehensive comparison would be hard, but just by straight instructions
per second: An old 6502 is probably 1/2 a MIP with each instruction dealing
with 8 bits. A new AMD Ryzen is 350,000 MIPS, with each instruction able to
deal with 64 bits. So, 700k times faster, not including the difference between
8bit and 64bit.

~~~
arya169
Man, that video makes me appreciate my old TI-83 so much more, even with its
lower resolution...

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vain
I spent an entire night typing this into my Commodore 64. And it didn't work.
I also messed up the save to tape, and never had the patience to type it all
over again.

Real world software programming was hard, and it still is. It remains just as
frustrating when it doesn't work.

~~~
RickJWagner
Great story! I remember typing in a few 'magazine programs' also, on my
Vic-20.

~~~
mysterydip
The most frustrating part for me with those magazine programs was the number
of them written for a computer other than mine. I drooled over all the cool
C64 game programs, then went over to my section and typed in some ascii maze
or text adventure.

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Solomoriah
I was in college about this time; did a lot of programming on the Apple //e. I
didn't have one, but the college I attended had a lab full of them in the
business department, and a lab full of boring green-screen IBMs in the
computer science department. What can I say, I like color. I wrote a bunch of
Apple code that is long gone and not lamented, and created some RPG materials
that I did rescue from the floppys a couple of decades ago.

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jnurmine
I typed this into a Commodore C64 with a kid next door. It felt like an
eternity to type those rows.

The first time something was bad and we had to debug. The disappointment was
tremendous.

The next time it worked, and felt magical how all that sweat and effort and
those nonsense numbers became Alfred.

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mixmastamyk
"What me worry?"

Interesting, loved MAD and had a VIC-20 early in the eighties, but think by
'85 (the days of Miami Vice) I'd already put it into storage. So, while the
issue looks familiar, don't think I tried it.

I have most of my MADs in a box around here somewhere.

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kstrauser
I noticed that most of the DATA numbers were negative. I swapped the signs on
all the numbers, and that saved about 250 characters. That would have added up
when lots of machines still had 16KB of RAM.

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unforeseen9991
I used to do these all the time, I think it was mainly from Byte magazines I
would get from the library. It was on a TI-994A. External floppy drives were a
godsend over the tape machine.

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newzisgud
I remember being 8 years old, having a real copy of this magazine and typing
this into my TI-99/4A. It worked. It was amazing.

This silly program undoubtably helped me get interested in technology.

