Very new to ASM. Where to start?

Expert (88)

04-09-2005, 15:23

Hey everyone. It's nice to see that MSX is still so very alive. I've owned an MSX 1 (VG8020) since I was about 12, and I've written quite a lot of simple BASIC games back in the days. I have a couple of MSX computers right now, and I'd really like to learn to code ASM on my F700D. I don't plan to "release" anything, I just want to have some fun with ASM and try if I can get some sprites to pop up, that sort of thing.

My problem: I know where to find information about ASM, it's been linked in quite a number of topics. I don't know *how* to code ASM, though. Is there a ROM I should buy that has an ASM-compiler, or do I write ASM in DATA-lines in BASIC or something like that? I have no idea where to put my ASM code, let alone compile it, heh.

Por wolf_

Ambassador_ (9950)

04-09-2005, 15:26

There are a number of assemblers available.. WB-Ass2, Compass, etc. on MSX and TNIasm, Sjasm etc. on PC (crossdev.)

Here's a lot to find: http://map.tni.nl/
http://icarus.ticalc.org/articles/z80_faq.html

Perhaps you can try to find a number of Z80 books..

You need some databook of the MSX vdp chips as well I guess..

And you need to ask around here.. plenty o' coders ready to assist!

Por norakomi

Paragon (1121)

04-09-2005, 16:44

Hey Mirg !!!

Welcome man !!
I just started assembly less than a year ago, and I love it so much !!!
What I'm using is Wbass2 (downloadable wherever), which is a great assembler.
Flop it in your msx, or use an emulator (Bluemsx is great) and the assembler starts.
type: EDIT to start coding......

you have to start coding at an address in memory, (with an msx having 64 kb memory,
you can start coding at address $0000-$FFFF)
the string ($) is for hexadecimal.

O.k. I'll try to make it simple by using some examples, that works best for me....

Lets say you want to start coding at memory location $C000

Then when the computer boots and Wbass2 is loaded you type

EDIT

(then in the editor you type

ORG $C000 (this means you programm starts at address $C000)

then you can load something into variable a like:

ld a,"H" (load a with the symbol "H")
or
ld a,50 (load a with the value "50", you can compare this with the basic instruction a=50)

You can print to screen whatever is inside variable a by typing

call $a2

end the programm by typing RET

so the program to print whatever is in "a" to screen looks like this:

ORG $C000
ld a,"t"
call $a2
ret

then go back to the assembler (control-c)

and assemble the programm into memory by typing:
ASM

after that run the programm by typing
GO $C000

O.k. reading the manual from WBASS2 teaches you much.....

about sprites
http://www.funet.fi/pub/msx/programming/asm/sources/
there is an assembly file called stars.asm which shows stars (1 dot sprites) moving horizontaly over the screen. Check it out, it's an intersting small piece of code.

anyway,

remember that you can allways come here for questions, everybody here is incredibly nice and helpfull !!!

HAVE FUN !!!

Por wolf_

Ambassador_ (9950)

04-09-2005, 18:36

more info: http://www.z80.info/lesson1.htm

Por Mirg

Expert (88)

05-09-2005, 10:32

Thanks for the great links, guys! I'm giving WBASS2 a whirl this evening. I've been brushing up my BASIC (woohoo) a bit to understand how the MSX worked with sprites / pages / etc again, heh.

Por ARTRAG

Enlighted (6830)