Also, the joystick ports on the back of the Apple III are arranged such that some games won't work properly in Emulation mode. Most joystick oriented games will use PDL (0) and PDL (1) for X-Y control. The ports on the Apple III put these signals on different connectors. Here are the Apple II Emulation Mode equivalents of the signals available on ports A and B.
pin Port A Port B
4 PDL (0) PDL (1)
5 PB1 PB2
8 PDL (2) PDL (3)
9 PB3