Mega Drive region coding

From Sega Retro

More than any other Sega system, the Sega Mega Drive is affected by differing forms of region coding, implemented so that games were optimised for (or locked out of) three main marketing regions; NTSC-J (Japan and parts of Asia), NTSC-U (North America) and PAL (Europe and Australia).

Like the Sega Master System and rival console the Nintendo Entertainment System, Japanese cartridges are a different physical shape to their Western counterparts, meaning Japanese games could not be played on American systems or vice versa without some sort of adapter (or by disassambling cartridges or consoles). However, Mega Drive hardware is also configured to be one of the three aforementioned regions, meaning software could adjust itself depending on what sort of Mega Drive system is detected.

The latter is not an unusual practice (and indeed similar methods were employed for many consoles going forward), however unlike more modern systems, software was under no obligation to adapt to the detected region, meaning only part of the Mega Drive's game library takes note of what type of system is in use.

The following details games which are known to have issues running in certain regions:

Region locked games

These games are designed so that they will not run at all on certain consoles. Usually a message is displayed informing the user that the game cannot be played. The Japanese version of Namco's Rolling Thunder 2 was reportedly the first Mega Drive game to be region locked[1].

NTSC-J consoles

NTSC-U consoles

PAL consoles

Games which display a blank screen

While we can assume these games are also region locked (given that they refuse to boot in certain regions), nothing of value is displayed on-screen, which could suggest the game has not been programmed to handle the incorrect regions.

NTSC-J consoles

NTSC-U consoles

PAL consoles

Games which break

In certain circumstances, games will attempt to run in the wrong region, only to break further down the line.

NTSC-J consoles

NTSC-U consoles

PAL consoles

Unoptimised games

PAL and NTSC systems run at different speeds and can support different screen resolutions. In some cases, no effort is made to optimise for each system, leading PAL games to run too slow (with borders), or NTSC games to run too fast (or have visual elements drawn off-screen).

Many PAL titles, particularly earlier prints, are notorious for running noticably slower than their NTSC counterparts, leading many to import or modify their consoles to fix the speed issue. Unoptimised NTSC games are far rarer, and usually consist of European-developed games not being adjusted correctly.

NTSC-J consoles

NTSC-U consoles

PAL consoles

Partially-optimised games

By 1992 efforts were being made on behalf of developers to ensure that games were at least partially optimised for PAL systems. While optimisations vary, usually this involved speeding up the music, as opposed to speeding up the game logic.

NTSC-J consoles

NTSC-U consoles

PAL consoles

References