| ??? 08/09/06 19:18 Read: times |
#121925 - I would not, the user does Responding to: ???'s previous message |
Where would you want to wire-OR rows and columns, and why
I would not, the user does when he presses 2 keys simultaneously. This, in effect connect two outputs. Now visualize that you scan with out (row or column - your choice) high and the user press two keys connecting everything to a low out. So, for multiple presses with low on selected out you get multikey, with high on selected out, you get no key. The 'no key' most likely will be preceeded as well as followed by a key read. SO with low selected out you know the user is funbling, with high out you do not. Erik |
| Topic | Author | Date |
| High or Low in keypad scanner? | 01/01/70 00:00 | |
| PNP? | 01/01/70 00:00 | |
| maybe with TTL, but what about CMOS? | 01/01/70 00:00 | |
| I would not, the user does | 01/01/70 00:00 | |
| that depends on how you scan the inputs | 01/01/70 00:00 | |
| physical/technological reasons | 01/01/70 00:00 | |
| What sorts of reasons? | 01/01/70 00:00 | |
| early MOS technology | 01/01/70 00:00 | |
| Maybe they did it... | 01/01/70 00:00 | |
| Oxymoron! | 01/01/70 00:00 | |
| you spoilt my joke now | 01/01/70 00:00 | |
| Jokes | 01/01/70 00:00 | |
| We are living in a TTL world... | 01/01/70 00:00 | |
| I don't know why this interests me, but ... | 01/01/70 00:00 | |
| a proverbial answer | 01/01/70 00:00 | |
| So you figure it's just a matter of preference? | 01/01/70 00:00 | |
| You really should get out more! | 01/01/70 00:00 | |
Yes, it's a second childhood ... or maybe a third | 01/01/70 00:00 |