# TI-99/4A Keyboard

UNKNOWN connector (inside the console) Red wire is #15

Pin | 12 | 13 | 14 | 15 | 9 | 8 | 6
--- | --- | --- | --- | --- | --- | --- | ---
5 | = | . | , | M | N | /
4 | space | L | K | J | H | ;
1 | enter | O | I | U | Y | P
2 |  | 9 | 8 | 7 | 6 | 0
7 | fctn | 2 | 3 | 4 | 5 | 1 | lock
3 | shift | S | D | F | G | A
10 | ctrl | W | E | R | T | Q
11 |  | X | C | V | B | Z

Note:
Pressing a key closes the contact between corresponding row + column. Since there are no diodes to prevent current going backwards, pressing 3 keys at a time often results in appearance of a "phantom" key at the 4th corner of the square formed by these keys (e.g 8+7+3=phantom 4: current goes pin15-7-8-3-pin7 as if 4 were pressed).

Contributor: Joakim Ögren

Source:
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Document last modified: 2000-07-09