Math Quickie [TI-ASM]

thegamefreak0134 · Post by **thegamefreak0134** » Thu 10 Aug, 2006 2:26 pm

Two questions:

How do you divide in asm? Really, I think I only need to divide by 100, because I can shift for most of the other calculations.

How do you take a square root? This doesn't have to be fast or anything, and I'm actually shooting for size. I just don't really know how to do this as all. I would just use a bios call, but alas! My ops are currently tied up for storage stuff and can't be used. Darn.

Thanks if you can help.

-gamefreak

Post by **benryves** » Thu 10 Aug, 2006 2:29 pm

Z80 bits to the rescue.

thegamefreak0134 · Post by **thegamefreak0134** » Fri 11 Aug, 2006 3:10 pm

This is totally awesome. It has, like, everything that has ever bugged me ever on a calc in asm. This should make my formula work muuuuch easier. Thanks! (how long has this been here that I haven't known about it? Who knows...)

It doesn't go into square roots, which is still a problem, as I need them to deal with StatEXP properly. I need to take thesquare root of a 16-bit number and output it somewhere. I really need it to go into the lower half of a 16-bit register, because although the biggest number the routine can output is 255, I have to go off and increment that. (although I could just check it and load the value at that point...) I can't even work through how to tae a square root in BASIC (or on paper for that matter) without using the built in function.

BTW, this will not be used very often, so speed is of no concern. In fact, size is of much bigger concern.

Thanks!

-gamefreak

CoBB · Post by **CoBB** » Fri 11 Aug, 2006 3:45 pm

This is a newer version of the same page, square root discussion included:

http://baze.au.com/misc/z80bits.html

Post by **benryves** » Fri 11 Aug, 2006 5:40 pm

Ah, thanks. I knew there was a more up-to-date page, just couldn't find it :\

Jim e · Post by **Jim e** » Fri 11 Aug, 2006 6:18 pm

For Square roots I put this up on the wiki.
http://wikiti.denglend.net/index.php?ti ... quare_root

I have to read cobbs though.

thegamefreak0134 · Post by **thegamefreak0134** » Sat 12 Aug, 2006 3:48 pm

Just one quick question: Does "unrolling" a piece of code mean to repeat it a certain number of times?

chickendude · Post by **chickendude** » Sat 12 Aug, 2006 3:58 pm

ld b,3
loop:
inc a
djnz loop

unrolled would be

inc a
inc a
inc a

so, yes.

thegamefreak0134 · Post by **thegamefreak0134** » Sat 12 Aug, 2006 4:27 pm

Cool. OK, provided I get this to work (shouldn't be too dificult) I'll be designing the pokemon data arrays per pokemon and will likely be working on stat pages, with the exception that everything will be re-calculated in these versions rather than simply displaying a pre-calculated stat like the actual game will do (to be faithful and all.) I'll even make a little feature that, based on status and stats and whatnot, shows the min and max ammounts of damage a given pokemon's attack will do to another pokemon in your party. All of this was being hindered by a stupid divide operation. Thanks a million y'all!

-gamefreak