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Thomson (MO/TO / Theodore)

Thomson - MO/TO (Theodore) icon Thomson - MO/TO (Theodore) logo

Overview

The Thomson MO/TO (a.k.a. Theodore) family are 1980s French home computers built around the Motorola 6809. REG-Linux exposes the thomson metadata group and runs the libretro: theodore core so their cassette/disk images are playable.

Technical specifications

  • CPU: Motorola 6809E running at 1.79 MHz in the MO5/MO6/Tutor series with bank switching for memory extensions.
  • Memory: 48 KB RAM (expandable via side cartridges and floppy expansions) plus 32 KB ROM for the built-in BASIC interpreter.
  • Display: Thomson VDG offering 320×200 or 320×240 graphics with 16 colors plus firmware-assisted text modes.
  • Sound: Texas Instruments SN76489A PSG providing three tone channels and one noise channel through the onboard speaker.

Quick reference

  • ROM folder: /userdata/roms/thomson
  • Accepted formats: .fd, .sap, .k7, .m7, .m5, .rom, .zip, .7z
  • Emulator: libretro: theodore
  • System group: thomson, arcade

ROMs

Copy Thomson cassette (.k7, .m7) and disk (.fd) dumps into /userdata/roms/thomson. The core accepts zipped archives as long as the ROM files live at the archive root, so do not nest directories inside the zip.

Emulator settings

RetroArch’s Quick Menu ([HOTKEY] + south face button) controls video, shader, audio and input options through the thomson.* option tree. The core also exposes global.thodor_* features for rewinding, pad-to-keyboard mapping, and lightgun emulation where needed.

Controls

Consult the Thomson keyboard overlay (from the controller overlay repo) to map keys or use /remapping_controls_per_emulator for any custom assignments when a game relies on special buttons.

Troubleshooting

  • Ensure each archive contains clean .rom or .fd files; rename them to match the original release when necessary.
  • Toggle thomson.video_allow_rotate if the display orientation seems flipped.
  • Visit the generic support pages for additional RetroArch assistance.