Thomson 8-bit computer emulation with MESS

This page documents my MESS drivers to emulate the family of 8-bit French micro-computers built by Thomson in the 80's.

These drivers are included in the MESS multi-emulator, starting form version 0.108.

[T9000] [TO7] [TO7/70] [MO5]
[TO8] [TO8D] [TO9]
[TO9+] [MO6] [MO5NR] [Olivetti Prodest PC128]

[ Version française ]



An emulator is never finished!

It always has bugs, features that are not yet implemented, software that will not work as expected, etc. See the list of known issues and, please, be patient. The drivers are in constant evolution, and this documentation may lag a little bit behind the implementation.

You can also help me improve the emulation.

Driver List

The whole 8-bit Thomson computer family is emulated, starting from the T9000 prototype to the latest MO6. This includes a few rare versions (such as the MO5E or an Arabic TO7/70). Additionally, the Olivetti Prodest PC 128 (Italian clone of the MO6 built by Thomson and distributed by Olivetti) is emulated.

Click on a driver to access its documentation:

Driver list
t9000 T9000 Early TO7 prototype
to7 TO7 First commercialized Thomson computer
to770 TO7/70 Enhanced TO7
to770a TO7/70 Arabic TO7/70 with Arabic support
mo5 MO5 Entry-game, TO7-incompatible
mo5e MO5E MO5 export version
to9 TO9 Professional-looking computer, TO7-compatible
to8 TO8 Next-generation of TO7/70, Amiga-looking
to8d TO8D TO8 with integrated floppy
to9p TO9+ TO9 successor, based on TO8 technology
mo6 MO6 MO5 successor, based on TO8 technology
mo5nr MO5NR Network-aware MO5-MO6 hybrid
pro128 Olivetti Prodest PC 128 Italian MO6 built by Thomson

The few 16-bit computers built by Thomson (TO16, Micromega 16, Micromega 32) are not emulated.


Input Devices

The following input devices are available for all machines:

A few notes:

Storage Devices

Here is a list of devices than can be connected to an image file, as well as the image formats they support:

Device list
TypeMESS optionFile format Read / write
cartridge-cart filename .m5, .m7, .rom read-only
cassette-cass filename .k5, .k7, .wavread and write
floppy -flop0 filename
-flop1 filename
-flop2 filename
-flop3 filename
.fd, .qd, .sapread and write
printer-prin filename ASCII filewrite-only

A few tips and tricks:

Communication Devices

The RS232, MODEM, and network extensions are not yet supported.

Sound Devices

The internal 1-bit buzzer is emulated (except on the TO8(D) where there is none).

The 6-bit DAC is also emulated (it is integrated on the TO8(D), and present as an extension on other computers).

The speech synthesis extension (based on the MEA 8000 chip by Signaletics / Phillips) is now correctly emulated. You will need the latest SVN version. You will also need a special software to run on the emulated computer (e.g., Parole for TO7, TO7/70, TO9, and TO8). Finally, you need to make sure that the E7FE-F port is set to Speech in the configuration menu (as the port is shared with the MODEM extension).


All video modes are emulated, as well as the 4096 color palette and hardware page switching. The emulation is scan-line based, with accurate sync signals and timing. It should correctly render most demo effects (see the TO8 Chinese Stack demo by PULS). However, the video system still has some issues.

The TV overlay extension is not emulated. Nor is the TV digitization extension.

MESS now automatically switches resolution when it detects that a high resolution (640x200 not counting borders) mode is used. You no longer need to do this manually. MESS will switch back to low resolution (320x200) when high resolution is no longer as the later is somewhat costly.

Quick Start

The first thing to do is get and install MESS, SDLMESS, or MacSDLMESS (version 0.108 or better) and get the Thomson ROMs.

We now provide a few example command-lines (they should be adapted to your favorite MESS port or GUI):


Software image files were found on Daniel Coulom's site or on the Logiciel MOTO site.

Known Issues

First, a few non-issues:

Now for real issues that should be corrected at some point:

Finally, here is a list of corrected issues. You may need to get the latest SVN version to get the fix, though:

How you can help

You can help by testing the driver:

You can report the problem or submit patches to me by mail or (preferred) using MESS's Bugzilla (specify Thomson as component). Please report only problems that are not already known issues.

I am also looking for some missing information to complete the emulation:




For general question about MAME or MESS, please consult the relevant FAQ first:

If you have a question that is specific to the emulation of a Thomson computer using one of the mentioned MESS driver, feel free to contact the author.

Thomson Computers Links

Many websites dedicated to the Thomson computers are in French only.

MESS Links

Other Thomson Emulators

You may also find some Thomson software on these pages.


The MESS drivers for 8-bit Thomson computers were written by Antoine Miné.