The Ormatu is one of the many systems "software-compatible" with the Emerson Arcadia 2001.
Though, the Emerson Arcadia 2001 is the most popular system of this console group, it was not necessarily at the origin of it. Things must be seen differently. Philips / Signetics developped a hardware platform to demonstrate the possibilities of their Signetics 2650 & 2636 chipsets. Somehow, this hardware was licenced (by Philips?) to many third-companies around the world resulting in systems like the Interton VC-4000, Voltmace DataBase, Acetronic MPU-1000, ITMC MPT-05, etc.
Some times later, the hardware was improved, with the use of a Signetics 2637 instead of the 2636 (handling the audio & video), somehow resulting in a new wave of licenced systems, all based on the same hardware and playing the same games. This console group includes : the Emerson Arcadia 2001, Advision Home-Arcade, Prestige MPT-03, Tele-Fever, etc. and the Ormatu.
All these systems (based on the 2650 & 2637 chipsets) are "software-compatible" with each others. It means that they all could play each other games if their cartridge slots were identical (which is not the case, resulting in sub-groups).
The Ormatu Video Spelcomputer 2001 was marketed in the Netherlands (and Belgium?). The other systems using the same case & cartridge slot, and thus directly compatible with it, are the Sheen Home Video Centre 2001 (Australia) and the Intervision 2001/3001 (Finland, Spain, Switzerland?).
The Ormatu is equiped with two detachable controllers made of a screwable analog joystick and a 14-buttons keypad (rubber buttons). Small plastic layers were delivered with each game, explaining the different key functions when placed over the keypads (like with the Mattel Intellivision).
The Control panel is made of 4 buttons (Start, Clear, Select A and Select B) and the power switch.