MASM: EASY math

[ashtr3jd]

i would like to do the following in win32asm:

(XTimes = 0, from the beginning)
XTimes = XTimes + 1

Thanks in advance, help is always appreciated!

[Knight_Vision]

Looks to me that your wanting soemthing like this...

xtimes db 0

mov ax, 1

mov xtimes, ax

Hope this helps...

[ashtr3jd]

mov ax, 1

mov xtimes, ax

the last line gives me an error:
A2070: invalid instruction operands

.386
.model flat, stdcall  ; 32 bit memory model
option casemap :none  ; case sensitive

include \MASM32\INCLUDE\windows.inc
include \MASM32\INCLUDE\kernel32.inc
include \MASM32\INCLUDE\shell32.inc
include \MASM32\INCLUDE\masm32.inc
include \masm32\include\user32.inc

includelib \masm32\lib\user32.lib
includelib \MASM32\LIB\kernel32.lib
includelib \MASM32\LIB\shell32.lib
includelib \MASM32\LIB\masm32.lib

.data 
MsgCaption      db "test",0
xtimes db 0

.code 

start:

mov ax, 1 

mov xtimes, ax

invoke MessageBox, NULL, ADDR xtimes, ADDR MsgCaption, MB_OK

end start

[Knight_Vision]

Ahh bloody hell. I forgot you were using MASM. Yea, there is something you are supposed to do to the Variable first. I forgot what it is. I'll have to look it up.

In NASM all you had to do is what I shown you. Well accept add the brackets around the variable.

mov [xtimes],ax

I figured you knew this. For masm you may have to write it out something like this...

mov [xtimes offset],ax

I know it's probably wrong, but i'm trying this out of memory.. Like I said I would have to look it up.

[ChimpFace9000]

The problem is that your trying to move a word into a byte.

[Knight_Vision]

Dohh! I didn't catch that.. LOL Yea, chimpface is correct... It's desginated as a byte instead of a word, but AX is a 16 bit string or two bytes (Word).

So it wouldn't work. Just change it from db to dw.

[ashtr3jd]

xtimes dw 0
mov [xtimes],ax
mov [xtimes offset],ax

won't compile, gives an error

xtimes dw 0
mov ax,1
mov xtimes,ax

gives me weird character

/me bows to Knight_Vision & ChimpFace9000 and begs

[colio]

Hi.

It's simple.

to obtain
XTimes = XTimes + 1

[colio]

Hi.

It's simple.

to obtain
vb version -> XTimes = XTimes + 1
asm version -> inc byte ptr [xTimes]


This code asume xTime db 0


Regards

colio

[Darkwraith]

Why just:

INC [xtimes]

[MrDeX]

You have problem also with how you output the variable. You can't just output the contents of the register, you need to convert the number to a null terminated ASCII string first. I can't remember what the function is to do that but there's something in the MASM32 libraries which make it easy.

[Darkwraith]

However you might need to create your own (or find your own) depending on what assembler you use.

[silk.odyssey]

The masm32 library has a dwtoa function to convert a doubleword to a string.

[Darkwraith]

But will the masm32 libraries work with UNIX / Linux?

[art_sands]

You've got the source and you've got FASM. I don't think anything should stop you from converting code to FASM and then using it in Linux. Assembly language is not machine-independent (though I've found certain cornered places where people have claimed to have achieved that), but it sure is platform-independent.

Regards,
Art

[Darkwraith]

Depending on what you write, that is true. Interrupts (from what I dealt with) are not independent creatures.