Op amp homework problem

This is one simple way to control a LED, fan, relay or solenoid with a computer and a PIC.

Detecting, decoding, and displaying IR (Infrared) signal data is interesting, but using those signals to control stuff is more interesting . . . and sometimes useful. Read on to learn how.

We've all been there - you've spent hours and hours trying to get that sketch working, but somehow, you're not reacting well to time critical events in your system. Maybe it's a wireless peripheral indicating when a packet is ready. Maybe it's an external Flash device signaling when data is ready to be read out. Maybe it's as simple as a button push that you need to react quickly to! But, try as you might, it seems the best way to see these sort of events is to just `digitalRead()` that pin over and over in your main `loop()` function until something interesting happens. ...or is it?