DB9 Controller Comparison

Many systems use a modified Atari pinout for their controllers. Most of the time it's safe to use any one pad on another, but occasionally changes are made and you definitely want to avoid putting a pad into a system where pressing down shorts +5v to Ground and fries the machine.

PinSega 8-bit1) J-PC2) Amiga MegaDrive
1 Up Up Up Up
2 Down Down Down Down
3 Left Left Left Left
4 Right Right Right Right
5 +5v +5v - +5v
6 A A A A/B
7 - B +5V OSel3)
8 Ground OUT Ground Ground
9 B Ground B Start/C
1)
SG-1000, Mk3, Master System etc
2)
MSX, X68000, FM-Towns etc
3)
Output Select, switches between different button sets