| ??? 05/02/05 19:40 Read: times |
#92755 - no caveat when done right Responding to: ???'s previous message |
Today I like to use a serial FRAM (Ramtron) for backup of often changing variables. I wouldn't believe to the "store to EEPROM while power is dying" method, or, better, I think there might caveats in that method, too (although I never tried that, I admit).
from rectifier -*-> divider to port pin
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*-- diode -*- "7905" -- processor
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----- many uF
-----
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GndWith this setup you have all the time from the power is cut (- 10ms for 50 HZ) till the voltage on the "many uF" drop below the minumum input for the 7905.
Erik |
| Topic | Author | Date |
| Troubles in POWER DOWN mode | 01/01/70 00:00 | |
| what's exactly the problem? | 01/01/70 00:00 | |
| the problem... | 01/01/70 00:00 | |
| that's bad... | 01/01/70 00:00 | |
| you are right... | 01/01/70 00:00 | |
| the problem | 01/01/70 00:00 | |
| A possible solution? | 01/01/70 00:00 | |
| on chip permanent storage | 01/01/70 00:00 | |
| caveat | 01/01/70 00:00 | |
| no caveat when done right | 01/01/70 00:00 | |
| 79 ? | 01/01/70 00:00 | |
| oh well | 01/01/70 00:00 | |
| caveat | 01/01/70 00:00 | |
| non-caveats | 01/01/70 00:00 | |
| "1" when v.supervisor is not powered | 01/01/70 00:00 | |
| use open pin | 01/01/70 00:00 | |
| ideas | 01/01/70 00:00 | |
| your idea... | 01/01/70 00:00 | |
| it seems to me,it is working... | 01/01/70 00:00 | |
please do not | 01/01/70 00:00 | |
| I had an idea... | 01/01/70 00:00 | |
| i tried this... | 01/01/70 00:00 | |
| wow that's bad | 01/01/70 00:00 | |
| i tried this... | 01/01/70 00:00 |