jornada-dosbox

dosbox 0.74-3 fork with patches to be useful on Jornada 7xx running Linux:

• VGA code changed to output every 2nd scanline only in VGA mode to support half VGA screen
• VGA ROM font changed to look acceptable on half VGA screen
• Works on the commandline framebuffer device, doesn't require X11 overhead. Should work with X11 also though.
• Supports sound on the Jornada by using the snd-jornada720 driver from the kernelpatches repo.

Dependencies

apt-get install the below packages to your Jornada Linux CF card:

• automake
• autotools-dev
• libsdl1.2debian
• libsdl1.2-dev
• build-essential
• manpages-dev
• libevdev-dev
• libsdl-mixer(-dev) for ALSA sound support

apt-get install automake autotools-dev libsdl1.2debian libsdl1.2-dev build-essential manpages-dev libevdev-dev

Building

I'd suggest to use the desktop PC and QEMU running on the CF card, running this on the Jornada should also be possible but might take some serious time.

• Make sure dependencies are installed
• git clone this repo: git clone https://github.com/timob0/jornada-dosbox.git /opt/jornada-dosbox
• cd /opt/jornada-dosbox
• ./configure
• make
• make install

Running

dosbox from the commandline. If you see a garbled screen, thats because of permissions to the framebuffer device. Try to run as root then.

On the first run, it will create a .dosbox folder in your home drive and create a config file in there which you can tweak Some settings you would want to adjust:

• fullscreen=true
• frameskip=6
• scaler=none
• core=auto
• cputype=auto
• cycles=max
• Set the audio emulation to your liking, suggest to go with 22kHz or maybe even 11kHz sind it's quite heavy on the CPU. Be sure to use the snd-jornada720 from my kernelpatches repo and configure ALSA properly.

If you have a DOS folder on the FAT partition of your CF card for use with PocketDOS you can just mount it fine and use the programs from Linux. Add a mount C: /mnt/boot/YOURDOSFOLDER to the autoexec section of the config file

Limitations

• Only every 2nd scanline is being rendered to scale down standard VGA to the Jornada screen
• Emulation is not exactly quick, maybe at PC-XT level
• Touchscreen -> Mouse translation is ... not good
• dosbox relies on its own keyboard mapping, the console keyboard map is ignored