OpenTom

OpenTom is a tiny, open source Linux distribution for TomTom™ devices.

Getting Started

• Install the following dependencies: subversion chrpath fluid imagemagick xsltproc
• Set the ROOT envvar in get_cross_env.sh
• source get_cross_env.sh
• Run make to start the initial OpenTom build
• This may take a while; consider getting yourself a coffee ;-)
• Copy build/ttsystem (boot image) to the root folder of your SD card (backup the original one first!)
• Copy the contents of opentom_dist/ to a (new) folder called opentom on your SD card

How to build extra applications

• Run make extra and copy the files as described above
• For dosbox, dune2, gnuboy, linapple, and scummvm games: Take it from internet and copying it into opentom/share subdirectories.
• For coolreader: Run sudo updatedb in case the default font is not found.
• For Navit, you need the TomTom gltt (see below, that read raw GPS data from /dev/gps and send it to /var/run/gpspipe).

How to modify ttsystem

• For kernel: cd kernel; make menuconfig
• For busybox: cd build/busybox*; make menuconfig
• For initramfs: do your changes and touch initramfs/etc/rc
• Then: return to $ROOT and run make ttsystem

How to add some new applications

• Just extract you source into $ROOT/src (for libraries) or applications/src (or build if no patches should be applied)
• Run ./configure --prefix=$ARM_APPROOT --host=$T_ARCH (adapt accordingly in case the project is not based on Autoconf)
• Copy the final executable into $(TOMDIST)/bin
• Rune make verif_dist (inside $ROOT directory) to update used shared libs in opentom_dist
• Copy the files to your TomTom device
• If it works as you wish, make a patch (with make patch-<my_app_dir_name>) and update applications/Makefile

On the TomTom side

• When you boot your TomTom with OpenTom, you can directly use Telnet to login in as root from USB
• Use the built-in FTP server to update your files
• strace and gdb are ready to be used to debug your programs

Creating Nano-X test platform on your system

• Create $ROOT/i386 directory
• Extract, configure and install: microwin, nxlib (with libNX11), SDL, Fltk, ... (with LDFLAGS=-L/usr/local/lib --prefix=/usr/local)
• Try NetBeans to perform you developments?

How to free some memory (~3-4Mo on 32!)

Use an ext2 partion on your SDcard to replace (and free) initramfs with busybox pivot_root/chroot:

• Use fdisk to create two partitions on your SD card: partion1=vfat(TomTom), partition2=ext2(10Mo?)
• Copy ttsystem into SD.part1 and verify it boots, if not try to copy gns and program directory from original TomTom and others...
• When it boots:
• Verify that busybox include chroot and pivot_root,
• Copy the unmodified initramfs/* into linux SD partition, with /var/* linked to /tmp
• Copy the configs/etc_rc_ext2 to SD.part2/etc/rc
• Verify that kernel include ext2 filesystem support
• Copy configs/etc_rc_file.pivot_root_ext2 to initramfs/etc/rc
• make ttsystem
• Then on partition 1 copy build/ttsystem and the opentom_dist directory on SD.part1
• If something goes wrong, try configs/kernel_config.console_ext2 to activate kernel FrameBuffer console

How to install gltt from TomTom ttsystem file (for Navit)

• Copy your TomTom™ ttsystem file into $ROOT/src (e.g. cp /mnt/TOMTOM/ttsystem $ROOT/src/ttsystem.tomtom)
• cd $ROOT/src
• ttimgextract ttsystem.tomtom
• mkdir -p ttsystem.tomtom.initramfs
• cd ttsystem.tomtom.initramfs
• gunzip -c ../ttsystem.tomtom.0 | sudo cpio -i
• Now the boot ramdisk of your TomTom is extracted to $ROOT/src/ttsystem.tomtom.initramfs and the TomTom kernel is in $ROOT/src/ttsystem.1
• Then: cp $ROOT/src/ttsystem.tomtom.initramfs/bin/gltt $TOMDIST/bin

To-Do

• Fix espeak => portaudio => OSS, that currently don't work
• Patch spreadsheet to be adapted to TomTom screen

Support

• Checkout our documentation in docs/
• Take a look at the shell scripts, Makefiles and patches
• Feel free to send an email in case of a problem or if you found betters URLs for sources.txt (opentom@free.fr).

Authors

• Clément Gerardin (opentom@free.fr)