My version of Eiffel interface
Original project here: http://didier.mequignon.free.fr/eiffel-e.htm (local mirror: Eiffel.pdf)


EiffelST SCH.pdf
EiffelST PCB.pdf

Firmware: eiffel_i.hex
Cable: 1-1 2-2 3-3 4-4 5-5 6-6 (straight)
3d printed case (thanks to kkrys): 3D printed case.zip


There is a known issue with fire button in some games, like "Robin Hood Legend Quest" in official firmware.
But... Mq from polish forum atari.org.pl did some awesome work and modified this firmware:
http://www.atari.org.pl/forum/viewtopic.php?id=19470