Editing IBM PC AT (5170) (section)

== Keyboard ==

The AT shipped with a new '''84-key Model F AT''' keyboard. The numeric keypad is clearly separated from the main key group and three LEDs are present (Caps Lock / Scroll Lock / Num Lock). The connector is the same DIN-5 as the XT keyboard, but the electrical interface is '''bidirectional''' — the host can control the LEDs, reset the keyboard, set the typematic rate, etc. The scan code set is also different from the XT's. As a result, an XT keyboard cannot be used on an AT and vice versa without a protocol converter.

From April 1986 (Type 3 motherboard era), the AT shipped with the '''101-key Enhanced Keyboard''' (Model M).