Serial Port Echo with Arduino

Here is another example of using arduino with the serial port. I took an example from the arduino site here, and tinkered it. I wanted to create a program to echo the actual letter that you send through the Serial Monitor program. The example on the arduino site returns the ASCII values of the characters sent, so I tinkered it to send the actual characters back. So here is the program:

Motor Speed Control through a PC Serial Port with arduino

Last time I showed you how to "speak" to your arduino through a serial port. Today we will use that knowledge to control a motor! About a week ago I took apart an old CD Burner and found 3 motors. I will use one of those today.

The program is very straightforward, just like yesterday we send data from the Serial Monitor in the arduino program, the board "listens and responds" to them.

Here is a video of the program running, I explain the code after that.

Arduino Control over Serial Port

So let's build something more difficult. We will see how you can control arduino over a serial port. We turn the onboard LED on and off through the serial port.

Let's see the video of the program working and then we will explain the code.

Scavenging Components from Discarted Electronics

I took apart an old (about 10 years old :P) CD burner, I had in my closet, and found a wealth of components. 

I found 3(!) motors, about 15 transistors, one Green LED, surprisingly no resistors, at least no typical ones, one button switch which will work great for those digital input tutorials at arduino.

I also found one laser diode, that the CD burner used, which I broke trying to remove it.. It's too bad because they can make great laser pointers, or even work as lighters. 

Here are some images of the things I found:

Arduino UNO Programming Basics

So let's take the blink program and tinker it!

void setup() {               
  // initialize the digital pin as an output.
  // Pin 13 has an LED connected on most Arduino boards:
  pinMode(13, OUTPUT);    
}

void loop() {
  digitalWrite(13, HIGH);   // set the LED on
  delay(1000);              // wait for a second
  digitalWrite(13, LOW);    // set the LED off
  delay(1000);              // wait for a second
}