| ??? 06/06/06 14:51 Read: times |
#117869 - do you have any hardware knowledge Responding to: ???'s previous message |
visualize a port pin as a "wired OR" let ys take 3 transistors and connect the collectors together. Then a resistor to +5. If ANY of these transistors is ON, the outputb is low, if all are off, the output is high.
Erik |
| Topic | Author | Date |
| Help Understanding AT89C51 Datasheet | 01/01/70 00:00 | |
| logic gain and other | 01/01/70 00:00 | |
| Should I study more? | 01/01/70 00:00 | |
| do you have any hardware knowledge | 01/01/70 00:00 | |
| No hardware knowledge | 01/01/70 00:00 | |
| what purpose? | 01/01/70 00:00 | |
| Purpose | 01/01/70 00:00 | |
| many get confused by this | 01/01/70 00:00 | |
| Got it ! | 01/01/70 00:00 | |
| per-pin, per-port, and whole-chip limits | 01/01/70 00:00 | |
| strictly speaking... | 01/01/70 00:00 | |
| Slight oversimplification | 01/01/70 00:00 | |
| it used to be DC, now it is AC | 01/01/70 00:00 | |
"per pin" | 01/01/70 00:00 | |
| Good post! | 01/01/70 00:00 | |
| Excellent Community | 01/01/70 00:00 | |
| have you read "the bible" | 01/01/70 00:00 | |
| Yes, I have started | 01/01/70 00:00 |