MCODER2 Tutoral

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swensont
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MCODER2 Tutoral

Post by swensont »

After tinkering around with MCODER2, I decided to write up a short tutorial on using MCODER2, It is a 7 page PDF document that goes over the steps in using MCODER2, and includes a little cheatsheet with the different USR calls for MCODER2. Now, I'm not an expert at MCODER2, but I like to document what I learn and put it in an easy to use form for the next guy to learn MCODER2. Please review it and provide any feedback.

It is available on my new web page: https://sites.google.com/site/svenqhj/
(ok, It's Google Sites. Not perfect, but it's free.)

Also available on the same page is my previous tutorial on ZX81 Assembly and an update paper on One Dimesional Cellular Automata on the ZX81.

Tim Swenson
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siggi
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Re: MCODER2 Tutoral

Post by siggi »

Hi Tim
MCODER uses 16 bit integer values. Thus the highest number that MCODER can handle is 65535.

Thus the example for "floating point numbers"

Code: Select all

Here is an example:

3.14 x 2.76 = 8.6664 314 x 276 = 86664
would lead to an overflow/error, because the result 86664 cannot be handled in 16 bit integers used by MCODER.

Siggi

PS: Did you also play around with the POKEs given in the manual to change the defaults of MCODER?
My ZX81 web-server: online since 2007, running since dec. 2020 using ZeddyNet hardware
http://zx81.ddns.net/ZxTeaM
sirmorris
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Re: MCODER2 Tutoral

Post by sirmorris »

brilliant, thanks!
swensont
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Re: MCODER2 Tutoral

Post by swensont »

Siggi,

Thanks for pointing out the issue with the 16-bit variables. I've edited the paper to indicate this and changed the example to one what would not go over 64K. I've also added links in the website to the source code examples in the paper.

I have not tried the different pokes to modify MCODER2, mostly because I did not find them all that interesting for my purposes.

Tim Swenson
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GCHarder
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Re: MCODER2 Tutoral

Post by GCHarder »

I liked your paper and samples on the One Dimesional Cellular Automata on the ZX81.

Take a look at the ZX-LSYS which I just posted, you might find it interesting.

Regards;

Greg
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