| ??? 12/18/02 12:54 Read: times |
#34657 - RE: I had a similar project (continued) |
You do not need any external hardware to do that. Only what you need is a keypad (4x4),
4 LEDs and 4 1k resistors. All the rest is the matter of software you write. Connect 4 LEDs to 4 inputs used to scan keypad rows. Scan keypad at 50..100 ms interval. Key scan can be executed very fast (50 usec), the rest time drive LEDs. |
| Topic | Author | Date |
| help: inteface 8051 to keyboard | 01/01/70 00:00 | |
| RE: help: inteface 8051 to keyboard | 01/01/70 00:00 | |
| RE: help: inteface 8051 to keyboard | 01/01/70 00:00 | |
| I had a similar project | 01/01/70 00:00 | |
| I had a similar project (continued) | 01/01/70 00:00 | |
RE: I had a similar project (continued) | 01/01/70 00:00 | |
| RE: I had a similar project (continued) | 01/01/70 00:00 | |
| RE: I had a similar project (continued) | 01/01/70 00:00 | |
| RE: I had a similar project | 01/01/70 00:00 |