OpenTom

OpenTom is a tiny, open source Linux distribution for TomTom™ devices.
This repository was tested to be working on June 2020.

Getting started

Before proceeding, it is recommended to backup the original contents of your GPS's internal storage.

• Register the i386 architecture by executing sudo dpkg --add-architecture i386 (or the equivalent for your system)
• Install the following dependencies: autoconf chrpath fluid imagemagick libglib2.0-dev libtool subversion xsltproc gawk dh-autoreconf pkg-config libglib2.0-dev libc6:i386 libncurses5:i386 libstdc++6:i386 cmake
• Set the ROOT envvar in get_cross_env.sh
• Enter the root terminal (sudo su in Ubuntu)
• Execute source get_cross_env.sh
• Run make to start the initial OpenTom build*
  • This may take a while, as it will download and compile every system component
• Copy build/ttsystem (boot image) to the root folder of the GPS storage
• Copy the contents of opentom_dist/ to a (new) folder called opentom on the storage

*If an error like the following one appears during the compilation process...

Invalid configuration `x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized
make: *** [Makefile:288: arm-sysroot/usr/include/jpeglib.h] Error 2

...you can continue compiling by executing linux32 make

How to build extra applications

• Run make extra and copy the files as described above
• For dosbox dune2 gnuboy linapple and scummvm games: take them from the Internet and copy them 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).

Note: currently, sprsht freecell navit are disabled as they are not compiling correctly.

On the TomTom side

• The IP that the GPS uses is usually 192.168.1.10 (if it does not work, try 192.168.1.200)
• When you boot your TomTom with OpenTom, you can directly use Telnet to login in as root from USB (it is recommended to connect the device to Linux for maximum compatibility)
• Use the built-in FTP server to update your files
• strace and gdb are ready to be used to debug your programs

Untested guides

The following sections of this documentation have not been tested by me (@raulbalanza), so they are not guaranteed to be working as of June 2020.

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
• Run 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

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 the creators' documentation in docs/
• Take a look at the shell scripts, Makefiles and patches
• Check the original repository for the latest patches
• Send an email in case of a problem to any of the collaborators (mainly to the original creator).

Collaborators

• Clément Gerardin (opentom@free.fr): project creator and supporter
• Raúl Balanzá (contact@raulbalanza.me): project sources update and verification