What is it?

OpenC64MegaDrivePadAdapter is an Open Hardware adapter that allows the safe connection of a Sega Mega Drive (known as Genesis in the US) controller to a Commodore 64 or Amiga computer.

Why did you make it?

Despite being compatible at the physical level (i.e.: they use the same DB-9 connectors), Sega Mega Drive controllers are slightly different from the Atari-style joysticks (which the C64 uses) at the electrical level. These differences usually manifest themselves in the fact that certain keyboard keys are not responsive when a Sega Mega Drive pad is connected to a C64 computer, but the CIA chip may also get harmed as a result.

Since I think that the Sega Mega Drive controller is one of the best joypads which ever saw the light, I developed this simple adapter board, which is supposed to sit inbetween the computer and the controller. You should be able to keep it plugged into the computer and then connect the controller to it, but you can also use a joystick extension cord (widely available), if that makes it easier.

What makes it special?

Button B will work as the normal fire button, but this adapter also allows using Button C as the second fire button, for those games that support two buttons.

While this works out of the box, the adapter also allows to customize the button mapping to a certain degree: for instance, replacing UP with C might make some games more comfortable to play. This might be useful on the Amiga as well, so the adapter also supports an Amiga mode.

Finally, OpenC64MegaDrivePadAdapter is Open Hardware. If you make any modifications to the board, please contribute them back.

What's included?

If you buy the component kit, this is what you will get:

• 1xDB9 Male Connector
• 1xDB9 Female Connector
• 5x1n4148 Diode
• 2x2.2k Resistor
• 1x100k Resistor
• 1xBC547 Transistor (Or equivalent)
• 5x3-pin Header Strip
• 1x2-pin Header Strip
• 4xJumper Cap

Disclaimer

OpenC64MegaDrivePadAdapter is provided to you 'as is' and without any express or implied warranties whatsoever with respect to its functionality, operability or use, including, without limitation, any implied warranties of merchantability, fitness for a particular purpose or infringement. We expressly disclaim any liability whatsoever for any direct, indirect, consequential, incidental or special damages, including, without limitation, lost revenues, lost profits, losses resulting from business interruption or loss of data, regardless of the form of action or legal theory under which the liability may be asserted, even if advised of the possibility or likelihood of such damages.

Get Help

If you need help or have questions, you can join the official Telegram group.