CPU power consumption and clock speed

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rbhollabaugh
 
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CPU power consumption and clock speed

Post by rbhollabaugh »

In prep for an upcoming project I'm researching arduino and my favorite so far is the boarduino. If I can solve some of the issues I can go forward with the project. Thanks in advance!
Reading the 168 manual pages I see that power consumption goes way down as clock speed is lowered. Being that my application will be running on batteries I am very concerned about how much power the 168 is taking. My application is very simple and does not need fast speed nor any timing issues from my point of view.
Reading thru the posts here it looks like I'll need to change the bootloader and then some things in the compiler environment. However I don't know the details. Can anyone clue me in? How do I modify, compile and rewrite the bootloader on a boarduino?

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Post by adafruit »

youd need an avr programmer such as the usbtinyisp or avrisp to change it to an internal oscillator OR just swap out the resonator from 16mhz to 4mhz (the programming speed, however, would have to go down from 19200 to 4800 baud since the bootloader wasnt recompiled to realize it was going slower)

alternately, you can put it to sleep if its idle much of the time

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Post by rbhollabaugh »

OK, read about the usbtinyisp and it makes sense/

==
ladyada wrote:youd need an avr programmer such as the usbtinyisp or avrisp to change it to an internal oscillator OR just swap out the resonator from 16mhz to 4mhz (the programming speed, however, would have to go down from 19200 to 4800 baud since the bootloader wasnt recompiled to realize it was going slower)

alternately, you can put it to sleep if its idle much of the time

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