| ??? 05/03/05 07:19 Read: times |
#92777 - I had an idea... Responding to: ???'s previous message |
This is not going to solve Jacek's problem, but an idea I had back in the times we tried to backup the IRAM.
I thought, it could be possible to use an external oscillator to feed the clock input of the '51 and gate its clocks by the powerfail detector's output (rather than using the powerdown mode of the mcu itself). As there are 4-legged oscillators with gate input, the circuit could be rather trivial. The actual reset should be then derived from the backup voltage, so the mcu gets resetted only when the battery is inserted the first time or changed. I never had opportunity to try it, but what do you think, could this work? Jan Waclawek |
| 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 |