Subversion Repositories aysalia

Annotations for the Aysalia DOS I & II source codes
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CALLING FLOW
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When running under Windows:

        AyDos.exe (32 Bit PE) --> DOSBox (32 Bit PE) --> AyDos.exe (16 Bit COM) --> AyDos.mnu (16 Bit MZ) --> AyDos1/2.gam (16 Bit MZ)

        1. AyDos.exe (32 Bit PE) calls DOSBox.exe (32 Bit PE) with config DOSBox.conf
        2. DOSBox.conf starts AyDos.exe (16 Bit MZ) as autostart
        3. AyDos.exe (16 Bit COM) calls AyDos.mnu (16 Bit MZ)
        4. AyDos.mnu (16 Bit MZ) shows a menu and calls AyDos1.gam or AyDos2.gam (both 16 Bit MZ)
        
When running under DOS:

        AyDos.exe (16 Bit COM) --> AyDos.mnu (16 Bit MZ) --> AyDos1/2.gam (16 Bit MZ)

        1. AyDos.exe (16 Bit COM) calls AyDos.mnu (16 Bit MZ)
        2. AyDos.mnu (16 Bit MZ) shows a menu and calls AyDos1.gam or AyDos2.gam (both 16 Bit MZ)


AYDOS.EXE
---------

AyDos.exe is a "fat binary" which can be called by DOS and Windows.

In Windows mode, it calls DOSBox.exe with the arguments "-noconsole -conf DOSBox.conf" and
the working directory being the directory where the EXE file is located.
It also centers the DOSBox window and changes its window title and icon at runtime.

In DOS mode, it executes the application "AYDOS.MNU" (which is actually a COM-file
containing the menu code that will eventually call AYDOS1.GAM or AYDOS2.GAM which are
actually MZ-executables).

To create this fat binary, do the following:

1. Compile AyDos.exe with Delphi

2. Compile DosStub.com with TASM

3. With an hex editor, copy the contents of DosStub.com into AyDos.exe to offset 0x40


AYDOS1.GAM and AYDOS2.GAM
-------------------------

These games were developed and compiled in QuickBasic, but unfortunately the source code is lost.

The EXE files have been modified with a hex editor to fix some small issues.
A side effect of one fix is that the video mode is not reset when the game exists.
Therefore, the EXE files have been renamed to GAM and will be called by the menu/launcher executable,
which resets the video mode correctly, in addition in showing a menu.


DISTRIBUTE
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AyDos.exe
AyDos.mnu
AyDos1.gam
AyDos2.gam
DOSBox.exe
DOSBox.conf
SDL.dll (required by DOSBox)
SDL_net.dll (required by DOSBox)