my first ASM!

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nvictor

Joined: 17 Feb 2007
Posts: 31

nvictor

Didn't sleep this night for I wanted to run a working progry that I completely understand. After wandering between docs and docs, tutorials and tutorials I've ended at the beginning : the flat assembler programming tutorial Very Happy

I've made three conclusions:
1. I dont need to worry about code segment, data segment when writing .com programs. The CPU load the program in RAM at 100h and start executing instructions. And by the way this is my "hello world!" .com version

Code:

        org  100h

        mov ah,9
        mov dx,message
        int 21h
        mov ax,4c00h
        int 21h

message:
        db      'Hello World!',24h

2. to write .exe programs (which I don't know yet) the processus must be different from .com progries. I must find how...

3. to add more interactivity to my programs I need to learn more DOS interrupts codes. (that's what I'm doing right now)

18 Feb 2007, 12:45

rugxulo

Joined: 09 Aug 2005
Posts: 2341
Location: Usono (aka, USA)

rugxulo

online HTML version of Ralf Brown's interrupt list

Check the DOS subforum for some of my silly .COM examples (tiny .ZIP viewer or tiny LFN dir lister), which hopefully should help a bit, at least.

18 Feb 2007, 20:16

nvictor

Joined: 17 Feb 2007
Posts: 31

nvictor

They will definitely help. I've found a good book which I'm also reading. Very Happy

19 Feb 2007, 03:34

DOS386

Joined: 08 Dec 2006
Posts: 1901

DOS386

Quote:

to write .exe programs (which I don't know yet) the processus must be different from .com progries. I must find how...

Marginally: drop "org 100h", and add "format MZ // push cs // pop ds" Laughing

Works up to 64 KB, for bigger files some problems come up

_________________
Bug Nr.: 12345

Title: Hello World program compiles to 100 KB !!!

Status: Closed: NOT a Bug

19 Feb 2007, 13:07

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