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???
05/02/05 17:57
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#92745 - A possible solution?
Responding to: ???'s previous message
If I got it right Erik, all you need is a detector - a optocoupler or a relay connected to a (interupt) input pin on your micro. The verry first line in your "main" is a check if pin x.x is high or low. If it's low, you got mains. If not you call your powerdown rutine. This dosn't solve your initial problem - the micro will still power up, when the +5V to the supervisor disapears. The stunt however forces the micro in power down again.

You should note, that you will actually run the controller on the back up source for a few cycles EVERY time the unit is powered down!

I've thought about doing exactly what you did: Usig the on chip ram as non volataile, powered by a lithium cell or a supercap.

Is this okay, or is there a major caveat I havnt seen?


Kind regards

- og ha' en god dag

Per Guldmann



List of 24 messages in thread
TopicAuthorDate
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      

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