Ricardo Seixas wrote:
> 
>         I'd like to thanks all that replyed to my question.
>         In this circuit I'll use the method described by Mike Smith
> to store "battery used time" since I'm using nicad.
>         Using one or two EEPROM locations I can create a counter that
> increment every minute and, when a determined count (time) is reached
> I can display a message with a safety margin to recycle the battery.
>         When the battery is recharged I can press a button before turn-on
> the device then, at power-up the start routine check the button and if
> pressed reset the counter.
>         Another thing that flashed my mind is to use the EEPROM counter as a
> safety device so, when a preset used time (or number of power-up's)is
> reached the user at the next power-up MUST press a pre-determined sequence
> in the buttons, otherwise the device becomes useless.
>         To increment the counter on EEPROM every minute is no problem since
> 1x10^6 cycles (EEPROM safety margin)  = 694 days, 24 hours a day and, the
> circuit is used 2 or 3 times a day (one hour max.).
>         Note, this is note a comercial device.
>         Now, another question ...
> 
>         Do nicads self-discharge when not in use ?
>                 If yes Then
>                         this method becomes half useless
>                 End If
>         Loop
> 
> Thanks again.
> 
> Ricardo Seixas

Seixas,

O gravador PICgrammer vai indo bem? Qual m‡quina voc est‡ utilizando? Um Pentium?

Miguel.