Master System - Compatibility

Compatibility

The Mark III was backwards compatible with earlier SG-1000 titles. As well as the standard cartridge slot, it had a built-in slot, formerly known as expansion slot for Sega My Cards, which were physically identical to the cards for the Sega SG-1000 "Card Catcher" add-on.

The Mega Drive is backward compatible with the Master System, despite having a differently shaped cartridge slot. Sega developed a pass-through device for the Mega Drive, allowing Master System cartridges to be played on the newer system. It was called the Power Base Converter in the US, the Mega Adapter in Japan and the Master System Converter in Europe. The somewhat large device plugs into the Mega Drive's cartridge slot, covering the entire circular top of the system. Master System cartridges and cards can then be inserted into the device and played on the Mega Drive using Mega Drive controllers. Due to its size and shape, the converter will not fit properly with the Mega Drive II, necessitating the use of the Europe-only Master System Converter II, or a third-party converter cartridge.