Boarduino LED Optional? for Reduced Power Consumption

[jjhuser]

Searched the blog postings for tips on minimizing Boarduino power consumption. Found some interesting options using sleep timers. However, wanted to also verify that Boarduino power-on LED (full-time ON) was OK to leave disconnected. Would appreciate confirmation of this. THX.

[mtbf0]

sure, leave it off.

[StandardRockets]

While I have not looked at the data sheet I wonder, if you turned off the internal pull up resistors for the unused I/O pins, would that also help reduce the power consumption?

[uhe]

I'd leave the pull-ups alone until all the other options are used that are listed in the specific datasheet (e.g. watchdog, adc,..). AFAIR the datasheet of the ATmega168 doesn't mention pull-ups expicit in the power management section but there is a paragraph about pins in sleep modes.
If you measure, I'd be interested in the results

[mtbf0]

pull ups are off by default, are they not? i thought that to enable them one had to set the data direction register to input, then write a 1 to the output.

[uhe]

On the 168 they are. Wrinting a 1 to PORTxn is enough.