We interrupt this program to bring you a tutorial on… Arduino interrupts

Arduino interrupt tutorial

Ah yes… the wonderful and oft-misunderstood world of microcontroller interrupts.  Are you looking to build a project that relies on very precise timing or needs to react quickly to an input?  Then don’t change that channel, my friend.  In this tutorial we’ll cover what interrupts are, what they do, and how to use them.

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Hush little microprocessor… AVR and Arduino sleep mode basics

Using low power and sleep modes on the Arduino can drastically cut energy use.

Sleep and power saving modes are popular topics in the various AVR and Arduino communities.  How do I put my device to sleep?  How can I wake it up?  How can I control what does or doesn’t get turned off?  It took me a while to round up answers to all of these questions during my own hacking journey, so this post is an attempt to compile the basics in one place.

What do I need to know before putting my precious Arduino to sleep?

Putting your Arduino to sleep is not as drastic as, say, doing the same to the family pet, but there are a few things you should be aware of before you start. 

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Monitor home energy use for $20

Although it’s been around for a few years now, the Kill-a-Watt and other “outlet” power monitors have gotten a lot of press for their ability to highlight the power use of many household devices that are otherwise black boxes.  However, measuring your power usage 1 appliance at a time is difficult and time consuming.  Even if your energy provider isn’t thinking about smart metering yet, why not analyze the energy consumed by your whole house over time?

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