NES Development - A nOOb's Perspective

Are you new to 6502, NES, or even programming in general? Post any of your questions here. Remember - the only dumb question is the question that remains unasked.

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cartlemmy
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NES Development - A nOOb's Perspective

Post by cartlemmy »

I just wanted to let you all know that I will be chronicling my adventures in NES development, and hopefully when all is said and done the document will be useful to someone. I was also wondering if anyone could help me be reading it over for inaccuracies.

http://www.yibbleware.com/nes/
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Kasumi
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Post by Kasumi »

My cursory read through only reveals this.
Multiplication / Division: There are no multiplication or division instructions on the 6502, so if you need to do multiplication/division you must create your own functions. Basically you should try to avoid doing multiplication/division in your game engine when possible to keep things from running too slow.
6502 CPUs can multiply and divide and quite fast actually, but only by two. (and powers of two by extension)So it's only best to avoid multiplications and divisions by numbers other than two. And that's also the case where people need to write their functions.
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clueless
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Re: NES Development - A nOOb's Perspective

Post by clueless »

This web site is does not contain an RSS feed. That is entirely your choice. However, your content (is it a blog?) would be easier to follow (track updates on) if it were an RSS feed, or would at least be recognized by the google rss reader. Just my $0.02.
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cartlemmy
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Post by cartlemmy »

Kasumi wrote:6502 CPUs can multiply and divide and quite fast actually, but only by two. (and powers of two by extension).
Ah good point, bitwise shifts, correct? I guess I should mention that :)
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cartlemmy
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Re: NES Development - A nOOb's Perspective

Post by cartlemmy »

clueless wrote:This web site is does not contain an RSS feed. That is entirely your choice. However, your content (is it a blog?) would be easier to follow (track updates on) if it were an RSS feed, or would at least be recognized by the google rss reader. Just my $0.02.
I did not intend on releasing it as a blog, but just a single document. But that's a pretty cool idea, I might just do that. I've already set up a blog for Yibbleware, so it wouldn't be too hard.
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Kasumi
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Post by Kasumi »

cartlemmy wrote: Ah good point, bitwise shifts, correct? I guess I should mention that :)
Yes. LSR and ASL. And then ROR or ROL to expand it to 16 bits.
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