The Kids Take Their Turn

Tonight was the kids turn to build their own circuit from scratch, then write their own sketch from scratch.

We started out with a review. I even made an Impres presentation (that's the Open Office version of Power Point.) We reviewed the basic symbols in a schematic that we would use in today's project. Next, we went over the LED, it's properties, and how to determine the anode (+) and cathode (-) side. And, finally, we reviewed the code they would need for the project. This included integer variables, the setup() and loop() functions, analogWrite, pinMode, and a very long discussion about for loops and nested for loops. This eventually, somehow, got into a long discussion about bits and bytes. Now they know how to count in binary. lol!

Next, the kids built their circuit, taking turns installing and wiring 3 LEDs on the mini breadboard and connecting them to the Arduino. They connected the anodes to pins 1, 3, and 5 and the cathodes to pins 2, 4, and 6.

Finally, they wrote the code. The 7 year old wrote the initial comments and the setup() function and the 11 year old wrote the loop(). Debugging was a hoot. They quickly found out that this is case sensitive since it didn't even like the "VOID" before the setup() function.

Their assignment was to turn on and turn off all 3 LEDs in any manor they chose.

They decided to light LED3, pause 1 second, light LED2, pause 1 second, light LED3, and pause 1 second. Then fade LED3 off, LED2 off, and LED1 off. I was impressed with a few things.

1. My son (the 7 year old) really grasped the concept of variables, because when he wrote his loop in the setup, he chose to create a variable called "code" instead of "pin." This, to me, meant that he really understood that the variable was just a holding place with a name and whatever he chose to name it had no bearing on the program.
2. My daughter chose to fade out the LEDs. This required her to create a nested loop, making this a much more complex first sketch. Good to know she wasn't afraid to put everything she learned into practice.

Here's what they came up with:

//LED1=+1   -2
//LED2=+3 -4
//LED3=+5  -6

void setup(){
  for(int code=1;code<7;code++){
    pinMode(code,OUTPUT);
  }
}

void loop(){
  for(int led =5;led>=1;led=led-2){
    analogWrite(led,255);
    delay(1000);
  }
  for(int led =5;led>=1;led=led-2){
    for(int code=255;code>=0;code--){
      analogWrite(led,code);
      delay(10);  
    }
  }
}

Tomorrow, we start experimenting with the servo.