UNKNOW connector (inside the console)
- Red wire is n.15
- 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).
- Interfacing the PC
- Help with IBM-PC keyboard interfacing
- Interfacing the AT Keyboard
- Keyboard Wedge Techniques
- PC Keyboard FAQ
- PC Keyboard Page
- PS/2 Mouse/Keyboard Protocol