| ??? 02/14/06 06:25 Read: times |
#109909 - back in the old days ... Responding to: ???'s previous message |
One of my older encoded keyboards is discretely encode, using a 74150 data selector (multiplexer) and a 7442 data distributor (decoder) and a counter to drive them. If you wire the switches correctly you can generate, precisely, the standard ASCII code for a 16x8 matrix of keys. A little more logic is needed to make a caps-lock work, though.
I'd be surprised if there isn't quite a bit of detail about keyboard encoding on the www, even without lookup tables as used in the PC keyboard. However, it might be easier simply to use a PC keyboard and translate its output. There's plenty of data about that on the www. RE |
| Topic | Author | Date |
| interface qwerty keyboard with p89c51rd2 | 01/01/70 00:00 | |
| Interface matters, key layout does not | 01/01/70 00:00 | |
| interface pc AT keyboard | 01/01/70 00:00 | |
| Try this | 01/01/70 00:00 | |
| AT and PS/2 keyboards | 01/01/70 00:00 | |
| back in the old days ... | 01/01/70 00:00 | |
| interface pc AT keyboard | 01/01/70 00:00 | |
| For the PS/2 protocol see | 01/01/70 00:00 | |
| Philips appnote | 01/01/70 00:00 | |
Inrerface pc AT keyboard | 01/01/70 00:00 |