rigelscout wrote:
> Thanks...
>
> Actually, I set them as output and used an external 1K resistor.
>
> Karl
If you are setting them as output, do not use the 1 kohms resistor.
If the pin is set to UP level and the resistor is connected between the pin
and ground, you will have around 4.8mA flowing (considering 5V at VCC) in
each resistor. That is not necessary, waste of energy and probably heating
the chip without any reason.
Or you set them as output and leave them open, or set them as input and
install a resistor between the pin and VCC in the value of 10 kohms and 100
kohms. You can program the pin to have pullup or not. In case of
programming them as input without the pullup, then the external resistor to
VCC is really necessary.
Wagner Lipnharski - email: wagner@wagn...
UST Research Inc. - Development Director
http://www.ustr.net - Orlando Florida 32837
Licensed Consultant Atmel AVR _/_/_/_/_/_/
question on unused pins
Started by ●October 23, 2003
Reply by ●October 27, 20032003-10-27
