Pioneer UC-V102
This page was last modified 10:42, 14 April 2019 by Rderooy. Based on work by Gdx and Mars2000you and others.



The Pioneer UC-V102, also called O-THE, is a Videodisc controller for "Level 3" interactive systems. It is meant to be used in combination with a Laserdisc Player and the Pioneer SS-D1 video buffer. It was marketed in Japan, Europe and the US. The system is really an MSX2, but without the MSX logo.

Unlike most Hidden MSX systems, getting to MSX-BASIC and running MSX software on it is very easy. If you switch it on, you will not see the MSX boot logo, but you will go straight to the BASIC prompt. Disks and Cartridges can be used just like with any other MSX system.

Brand Pioneer (probably made by Mitsubishi)
Type UC-V102
Year 1987
Region Europe, Japan, US
Original price
RAM 64kB in slot 0-2
VRAM 128kB
Media MSX cartridges, Dual 720KB FDD
Video Yamaha V9938
Audio PSG
Chipset Yamaha S1985
Extras Kanji-ROM, RS232-C, Superimposer


Pioneer UC-V102


Software side, this machine has MSX-BASIC 2.0

Slot Map

Slot Slot Slot
0-0 0-1 0-2 0-3 Slot 1 2-0 2-1 2-2 2-3 3-0 3-1 3-2 3-3
Page C000h~FFFFh 128kB
Page 8000h~BFFFh
Page 4000h~7FFFh Main-ROM RS-232C
Page 0000h~3FFFh Sub-ROM Disk ROM
  • The RS-232C ROM is a 8kB ROM - 4000h-5FFFh
  • ES = Expansion Slot - Each Internal Expansion card slot connects to two sub-slots


  • RGB output (SCART)
  • Tree sets of RCA Video+Audio input connectors
  • One set of RCA Video+Audio output connectors
  • Keyboard (Hirose QM40-26PA-EP)
  • Centronics compatible Parallel port for a printer
  • 2 general connectors (Joysticks, Mouse, Paddle controllers, etc)* RS-232C (25 pin female)
  • 1 cartridge slot
  • Three 100-pin custom expansion card slots
  • Two 3.5" DD FDD
  • power cable
  • AC Outlet

Note: No Data recorder connector!

External Links