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mbarton
December 3rd, 2004, 10:19 AM
Greetings, fellow vintage computer enthusiasts!

This is a request for all of those folks who spent time typing in games from books or magazines. I'm thinking of the games (mostly in basic) that could be found printed in Creative Computing and other computer magazines. If you have some experiences typing in programs from magazines and books, and don't mind sharing them with a researcher, please answer the following questions:

1. How old were you?
2. Why did you type in games?
3. What was the experience like? (the highs and lows)
4. Did you ever try to modify the code? Examples of what happened?
5. Do you feel you learned anything from this experience?

If you have experiences in this area, please answer the questions. I intend to use this information in my upcoming article in Armchair Arcade, so please indicate if you DON'T want me to reference your post in my article.

Thanks,

Matt Barton

mryon
December 3rd, 2004, 03:06 PM
1. I was about 10-12 or so.

2. because they are almost free ;)

3. somewhere between christmas morning and discovering the new world (when they worked).

4. yes, mostly just simple things like colour changes, etc.

5. I learned quite a bit of patience. ;) and that a disc drive was a great investment on a Vic-20, although that was had it's own set of troubles.

cheers,
mikol

Jorg
December 4th, 2004, 02:38 AM
1. How old were you?
13-16

2. Why did you type in games?
because they were there? Curious for the result I think

3. What was the experience like? (the highs and lows)
Highs: definitely the moment that checksum codes appeared behind all those lines of DATA 12,42,523,634,62,1,5,3,7,33,676,4.....
Lows: Searching for the error (without checksums)

4. Did you ever try to modify the code? Examples of what happened?
Yes, strange coloured sprites mainly..

5. Do you feel you learned anything from this experience?
Well, patience for sure, and a lot of peek/poke codes (I had a C64)

mbarton
December 4th, 2004, 05:25 AM
Ah, yes, the peeks and pokes. You know, to this day I don't know what those were for. Some kind of machine language? I always wondered how those programmers were able to figure out how to use them.

If anyone can explain "peeks and pokes," I'd love to learn more.

carlsson
December 5th, 2004, 01:26 PM
1. About 10-20 years old (in the end, shorter snippets from a magazine)
2. I typed in the listings because they were there - meant to be typed in, I mean. Also the excitement to see what it would become.
3. The experience would be everything from very disappointed, if the description or screenshot didn't match the result or if it was buggy, to much pleased. I never considered getting as far as submitting my own listing though.
4. I can't recall any particular modifications, but sometimes I typed in a listing for one type of computer onto my computer which was of a different kind and tried to figure out what the missing keywords were supposed to do - kind of "porting" then.
5. Certainly I learned more, both about my own machine and to a lesser extent the other. I also used David A. Lien's "BASIC Handbook" to look up possible explainations of unknown keywords.

I remember COMPUTE! often got the reader question if their conversion software could be obtained. As you may remember, they published each game for a handful of different computers - C64, VIC-20, Apple II, Atari 800, IBM PC, Tandy CoCo, TI-99 and so on. The truth was their "software" to convert listings consisted of the staff who rewrote each game to the platform, sometimes improving the original game if the machine had better abilities.

Oh, PEEK is a keyword that reads the contents of a memory cell. POKE then inserts a value into a memory cell. All your programs are stored cell by cell into memory. Some computers had memory mapped I/O which means in order to change colours, play music and change behavior of system, you need to POKE a lot of values directly into memory rather than go through a (non-existing) BASIC command. You could also on purpose POKE new values into the middle of your listing, so the listing would change as the program ran. This is called self-modifying code and probably very rare unless you are a skilled veteran programmer. If you know exactly what you're doing, it can be very effective but if you're randomly playing around, you can make the whole computer crash and thus need to recycle power.