Tiny Memory Model confusion

[dedndave]

if that's the case, then you are in pretty good shape
16-bit code may be viewed as a "fun little exercise"   :P

there are a variety of sources to help you learn assembler
one i like is Randy Hyde's older version of AoA
http://www.arl.wustl.edu/~lockwood/class/cs306/books/artofasm/toc.html
it isn't completely up to date, but it provides a lot of the basics you will need

in the masm32 package, the examples, help, and tutorial folders have a lot of great info   :U

[nmn]

Thanks. I think I'm off to a good start. With a bit of messing around, I got this to compile and run:

Code Select Expand


.386
.model flat, stdcall
option casemap:none
include    \masm32\include\windows.inc
include    \masm32\include\kernel32.inc
includelib \masm32\lib\kernel32.lib
include    \masm32\include\user32.inc
includelib \masm32\lib\user32.lib
.data
  Message db "Success.$"
  MsgTitle db "Hello MASM32!$"
.code
  start:
    push NULL
    push offset Message
    push offset MsgTitle
    push MB_OK
    call MessageBoxA
    push 0
    call ExitProcess
  end start

I don't want to drag this thread on, but is this in the right direction?

[dedndave]

looks good, except your parameters are reverse order   :P

in assembler, we have INC files - similar to H files in C
one that will save you some typing is \masm32\include\masm32rt.inc

also - MASM supports an internal macro called INVOKE
it will push the parms for you and make the call
it also does a little type-checking to see if the parms are dwords, at least
and that you have the correct number of parms...

Code Select Expand

        INCLUDE \masm32\include\masm32rt.inc

        .DATA

Message  db "Success.",0
MsgTitle db "Hello MASM32!",0

        .CODE

_main   PROC

        INVOKE  MessageBox,NULL,offset Message,offset MsgTitle,MB_OK
        INVOKE  ExitProcess,0

_main   ENDP

        END     _main

MessageBox is an alias for MessageBoxA
most ASCII functions have such aliases to make the code a little easier on the eye
only if you require the unicode equivalent do you need to specify MessageBoxW

[nmn]

Oh, that's useful. I should be paying more attention, I already saw invoke before. I'll be messing with this today, thanks for all of your help.

[dedndave]

oh - one more thing....

in win32, strings are often terminated with nulls rather than the old DOS '$'

[nmn]

Yeah, I did fix that, I just posted old code somehow.