Port availability[edit]
Older laptops and most contemporary motherboards have a single port that supports either a keyboard or a mouse. Sometimes the port also allows one of the devices to be connected to the two normally unused pins in the connector to allow both to be connected at once through a special splitter cable.[2] This configuration is common on IBM/Lenovo Thinkpad notebooks among many others.
The PS/2 keyboard interface was electrically the same as for the 5-pin DIN connector on former AT keyboards, and keyboards designed for one can be connected to the other with a simple wiring adapter. In contrast to this, the PS/2 mouse interface is substantially different from RS-232 (which was generally used for mice on PCs without PS/2 ports), but nonetheless many mice were made that could operate on both with a simple passive wiring adapter, where the mice would detect the presence of the adapter due to its wiring and then switch protocols accordingly.
PS/2 mouse and keyboard connectors have also been used in non-IBM PC-compatible computer systems, such as the DEC AlphaStation line, early IBM RS/6000 CHRP machines and SGI Indy, Indigo 2, and newer (Octane, etc.) computers.[3] Various Macintosh clone computers from the late 1990s featured PS/2 mouse and keyboard ports, including the Motorola StarMax and the Power Computing PowerBase