HowTo : DOSBOX integration

Reference
https://www.reddit.com/r/OdroidGo/comments/ftk4ib/guide_how_to_run_dos_games_on_oga_batocera/

RetroBat DOSbox behaviour
RetroBat uses standalone DOSBox-SVN, generates command lines like:
V:\RetroBat\emulators\dosbox\dosbox.exe "V:\RetroBat\roms\dos\Alien_Carnage.pc\dosbox.bat" -conf "V:\RetroBat\emulators\dosbox\dosbox.conf" -fullscreen -noconsole -exit -c "set ROOT=V:\RetroBat\roms\dos\Alien_Carnage.pc"

The generated command line option -conf "V:\RetroBat\emulators\dosbox\dosbox.conf" points to a non-existing file.
As fallback DOSBox will generate and use C:\Users\<youruser>\AppData\Local\DOSBox\dosbox-SVN.conf instead.

RetroBat ES behavior
- Scans files or folders with extension defined in es_systems.*.cfg templates, matches gamelist.xml when file/folder exists.
- Appends "/dosbox.bat" to results of previous step.

Instructions

*** STEP 1 unnecessary, kept for archive only ***
1) Edit Dosbox section in V:\RetroBat\system\templates\emulationstation\es_systems.*.cfg as described:
   <path>~\..\roms\dos</path>
   <extension>.pc</extension>

This ensures ES will only match the folders on your gamelist.xml for metadata and not files within the folder when scanning (as .pc is not a common extension)

2) If needed rename your DOSBox game folders adding the .pc extension to be matched. From the command line:
CD C:\RetroBat\roms\dos
FOR /D %f IN (*) DO REN %f %f.pc

*** STEP 3 is optional to manage options globally from a coventient folder, when you don't have a dosbox.conf in every game folder. *** 
3) Optional : Move C:\Users\<youruser>\AppData\Local\DOSBox\dosbox-SVN.conf to V:\RetroBat\emulators\dosbox\dosbox.conf

4) Review parameters at your dosbox.conf e.g. :
[sdl]
(...)
fullscreen       = true
fulldouble       = false
fullresolution   = desktop
windowresolution = original
output           = overlay  

[joystick]
(...)
timed         = false

Avoid output = surface as it doesn't support HW scaling and has problems with HDMI outputs.
Joystick timed = false solves a Tomb Raider spinning menu when a controller is attached.

5) Review gamelist.xml format, should include the folder and not any file:
<game>
<path>./Alien_Carnage.pc</path>
(...)
</game>

The parameter "/dosbox.bat" will be appended to the folder name at runtime, so ensure you have this file (e.g. rename AUTOEXEC.BAT to dosbox.bat if needed)

6) Relevant on any emulator you can kill DOSBox with CTRL-F9
https://www.dosbox.com/wiki/Special_Keys

You do not need point 1 at all it's already included and point 3 is useless as far as I know,but you need to have a dosbox.cfg file in your game .pc folder

Coincidentally I've just updated Batocera documentation / howto for dosbox last weekend and this should work on Retrobat too :
https://wiki.batocera.org/emulators:dos?s[]=dosbox

Hi @Voljega,

My experience was from migrating a Retropie bundle to Retrobat (e.g. renaming several AUTOEXEC.BAT files to dosbox.bat), and finding from emulatorLauncher.log how the standalone DOSBox parameters were generated.

It's the first time I read about a dosbox.cfg per game, those are indeed welcome news specially for the topics you mention in https://wiki.batocera.org/emulators:dos?s[]=dosbox#troubleshooting . Just because Tomb Raider needs timed=false, some other game might actually need the opposite.

I confirmed now point 1 was unnecessary as it scans files and folders at root level and not subfolders, updated the post accordingly, also on point 3 given the per-game settings.

Take care!

Bilu

To use Dosbox-Pure without choosing the executable everytime at game launch, I confirm that if you already have DOSBOX.BAT just add a file AUTOBOOT.DBP containing

Code:

C:\DOSBOX.BAT

in the same folder and it will load it automatically.

Sources:
https://github.com/schellingb/dosbox-pure/issues/28#issuecomment-751316413
https://github.com/schellingb/dosbox-pure#start-menu-with-auto-start