| ??? 12/21/04 00:34 Read: times |
#83554 - And finally the problem solved! Responding to: ???'s previous message |
Some info for whome interested : -I tested the current that needed to pull the pin completely dwon to zer when i write 1's to the port ,it was about 2.0 mA ! -Strongening the pulldown resistor CURENTLLY solved the problem !(changed the three 4.7k pulldwons with 1k's) .voltage levels are now 5 volt for 1 and 0.2 volt for 0 . -Using AT89S52/AT89C51/AT89C52 instead of the AT89S51 didn't helped and changed nothing . Maybe it would help others to mention to this problem as a design note in the design notes that Prahlad had been gathered from the froum users. ? my appreciation from whome that helped me out to solve this problem : Erik,Prahlad,Rusell,Andy,Kai Best Regards : Farshid J.H. |
| Topic | Author | Date |
| invalid voltage on a pulled up/down Port | 01/01/70 00:00 | |
| replace s with c | 01/01/70 00:00 | |
| Thats not the solution. | 01/01/70 00:00 | |
| please follow the main problem | 01/01/70 00:00 | |
| and some news | 01/01/70 00:00 | |
| s51 is good | 01/01/70 00:00 | |
| Pullup/down | 01/01/70 00:00 | |
| Sorry for Echo. | 01/01/70 00:00 | |
| pull up/downs | 01/01/70 00:00 | |
| pullup+pulldown = potential-divider? | 01/01/70 00:00 | |
| Potential, potential divider? | 01/01/70 00:00 | |
| potential divider / where wires go | 01/01/70 00:00 | |
| blow it | 01/01/70 00:00 | |
| don't blowed it (atleast not untill now) | 01/01/70 00:00 | |
| where does the wires go | 01/01/70 00:00 | |
| To Erik and others | 01/01/70 00:00 | |
| This will not work with 'C51s | 01/01/70 00:00 | |
| Exactly | 01/01/70 00:00 | |
| just got the point :) | 01/01/70 00:00 | |
| And finally the problem solved! | 01/01/70 00:00 | |
| I meant ++hundreds of microampere++ | 01/01/70 00:00 | |
| Wrong question ! | 01/01/70 00:00 | |
| Negative Logic? | 01/01/70 00:00 | |
Yes, negative logic! | 01/01/70 00:00 |