Note: I forgot to post my pics for this tutorial because I just moved into college at the time, and forogt to pack my USB cable for the camera.Anyway, on Monday, I promised you guys that I'll post a tutorial on how to connect a reed switch to Arduino. Well today, I'm here to keep my promise. Also, for the second time in this blog's history, this tutorial will be presented in Fritzing. So, what parts do you need for this tutorial?
- Arduino (1x)
- Reed Switch (1x)
- 10K Resistor (1x)
- Breadboard (1x)
- LED (1x)
- Magnet(1x)
- Wires(MISC.)
Okay, first connect a LED to pin 13 and Ground on the breadboard. We'll be using this to determine if Arduino detects the reed switch.
Now connect Arduino 5 volt and ground to its own buses. Then insert your reed switch onto your bread. Be care inserting this! When I finished this tutorial a couple days ago, I accidentally broke my reed switch by roughly inserting it onto my breadboard.
Now connect a 10K resistor from 5 volts to the reed switch.
Afterwards, connect Digital Pin 2 of the Arduino board where you connected your 10K resistor to the reed switch. Finally, connect the other pin of the reed switch to ground.
All done! Now open up Arduino's IDE and copy and paste this code onto a blank sketch book.
int ledPin = 13;
int inputPin = 2;
int val = 0;
void setup() {
pinMode(ledPin, OUTPUT);
pinMode(inputPin, INPUT);
}
void loop(){
val = digitalRead(inputPin);
if (val == LOW) {
digitalWrite(ledPin, LOW);
} else {
digitalWrite(ledPin, HIGH);
}
}
Upload the code! You should notice that the LED lights up automatically. Now grab a magnet and place it close to the reed switch. The LED should automatically turn off.
Well, that's it for me today. See you guys later!
Yeah....I find it real arkward that I did this experiment right after I did the reed switch to Arduino tutorial. Nevertheless, this is a very, very useful sensor. What sensor am I talking about? I'm talking about a Hall Sensor. Now, what's a hall sensor? A Hall sensor is a simple sensor that detects the presence of a magnetic field, and control its output depending on the strength of its field. Think of it as a far more sesnitive version of a reed switch. Anyway, I'll post a tutorial on how to connect a hall sensor to an Arduino board sometime in the future. Here's a video of the circuit in action. 
Over at Arduinofun.com, Shawn created a solar tracker using photoresistors, a servo, and a standalone Arduino board. Well, at first, I was reluncant on creating my own light tracker because Shawn did an amazing with his solar tracker. Anyway, last week, I'm in my dorm room, bored out of my mind, and have nothing to do. So, I pulled out my electronics box, and built my own light tracker. The experiment took me two hours creating the tracker (not including programming). Also, I would like to thank one of roommates for providing me the breadboard for the experiment. You rock dude. Anyway, here's the video of the experiment working. I'll post the source code for the experiment some time in the future.
A couple weeks ago, I recieved a package from Sparkfun.com. In that package was a magnet, another sensor which I will talk about later on this month, and a reed switch. For those who are unware, a reed switch is a regular switch that can only be activated when a magnet is near it. Although I would normally try to attach this type of switch to an Arduino board, I felt compelled to set up in a regular circuit. This Wednesday,I'll post a guide on how to connect this type of switch to your Arduino board. Well, that's it for me. See you guys on Wednesday.
