| ??? 08/26/09 06:34 Read: times |
#168550 - ghosting? Responding to: ???'s previous message |
You might probably experience ghosting, a known issue with switch matrices.
http://www.dribin.org/dave/keyboard/keyboard.pdf The solution is to add a diode in series of each switch. This might turn out to be bulkier than to add two cheap 74HCxxx-style shift registers and read out the dipswitch status serially. JW |
| Topic | Author | Date |
| dip-switch matrix trouble | 01/01/70 00:00 | |
| Need more information | 01/01/70 00:00 | |
| It's olá ... | 01/01/70 00:00 | |
| ghosting? | 01/01/70 00:00 | |
| Looks like ghosting | 01/01/70 00:00 | |
| Do you have two spare pins? | 01/01/70 00:00 | |
| Please tell us how you've wired your matrix | 01/01/70 00:00 | |
| My working matrix schematic* | 01/01/70 00:00 | |
| It looks OK, but... | 01/01/70 00:00 | |
| maybe, maybe not | 01/01/70 00:00 | |
| thats true | 01/01/70 00:00 | |
| External resistors for speed or reading slower | 01/01/70 00:00 | |
| noise, yes - but | 01/01/70 00:00 | |
| Different use of resistors | 01/01/70 00:00 | |
| I could be mean | 01/01/70 00:00 | |
| Was actually on topic ;) | 01/01/70 00:00 | |
| being off-topic or not... | 01/01/70 00:00 | |
| You need to show us the schematic and more | 01/01/70 00:00 | |
| he did | 01/01/70 00:00 | |
| Not quite enough | 01/01/70 00:00 | |
| not much code to show | 01/01/70 00:00 | |
=) Thanks for the +1 Informative =) | 01/01/70 00:00 |