Genesis:Genesis Controller on SMS Games

Most Master System games are fully compatible with a Sega Genesis controller. There are a few that don't work with Genesis controllers though. It's believed the reason for this is a Japanese/Export region check the games perform. Part of the region check toggles the select line on the controller port. It's supposed to be reset but these games fail to do that.

Incompatible Games

 * Alien Syndrome
 * Bomber Raid
 * Great Volleyball
 * Montazuma's Revenge
 * Penguin Land
 * Tennis Ace
 * Shanghai
 * Where in the World is Carmen Sandiego?
 * Wonder Boy in Monster Land

Flash Cart Fix
Thanks to huygens on the Everdrive forums, patches are available to fix these games for use with flash carts.

These were patched to reset the select lines (Please check crc of Patched rom if it doesn't work):
 * Montezuma's Revenge (8fc6bb9c)
 * Penguin Land (cb437bc2)
 * Wonder boy in Monster Land (cdc3c8df)
 * Where in the World is Carmen Sandiego? (c63e4d42)
 * Shanghai (91387e3f)

Bypass region detection code that writes to the select line:
 * Alien Syndrome (6b3e06ff)
 * Bomber Raid (c880978a)
 * Great Volleyball (bd29dabf)
 * Tennis Ace (b0b086bb)

Adaptor Cable Fix
It's possible to create an adaptor cable to workaround the issue. Credit phoenixdownita on the Everdrive forums.

Required Materials:
 * 9 pin Genesis/Megadrive controller extension cable
 * 9 pin Male to Female gender changer (really a tiny extender more than a gender changer)

Setup:
 * 1) Connect the extension cable to the console.
 * 2) Connect the gender changer female side to the male side on the extension cable.
 * 3) Snip pin 7 on the gender changer male side.
 * 4) Connect the controller cable to it.