On Tue, 22 Jan 2002, Edson Brusque wrote:

>
>         1) use the battery power when not using an external power suply.
 that's quite easy: use the same connector like all radios have ( with a
small switch )

>         2) charge the battery when an external power suply is available and
> power is off.

 that's a simple logic between power button and connector switch button

>         3) charge the battery even when power is on.

 charging circuit is on all the time

>         4) if the battery is at full charge, stop sending charging current
> to it.

 a comparator monitorize the battery level. Better with a nominal load
connected to battery (never in cheap devices )


All things above can be done without any microcontroller.

regards, Vasile

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