AVR-Chat

Hi Doug,

I'm fairly sure a few of the other guys are correct. It's likely that you have the port pin setup as an input, which means you are actually toggling the pullup resistor on that pin. Because there is no fet connecting it to ground, you are basically just charging up the capacitor (piezo) through the pullup resistor. 

Hein B
Auckland, New Zealand.


--- In AVR-Chat@yahoogroups.com, "doug_marysnowden" <doug_marysnowden@...> wrote:
>
> The PIEZO element is just a standard one that is supposed to be resonant around 24khz.  I disconnected the piezo and the port started toggling, as it should.  Should I put a pair of HEX invertor drivers in parallel for each output port to drive the piezo element?
> I am trying to build a small dog whistler, and am using a 9vdc battery, a 78L05 regulator for 5v to the Micro. 
> 
> Doug
>