/* 
Arduino test-code
This code is intended to be used for an easy introduction to the Arduino board. 
The program reads data from 2 digital and 2 analog ports and prints the values to the monitor with a sampling speed of 1 Hz.
*/

int counter = 0, analog0, analog1; //Creates variables as integers
float analog0_volt, analog1_volt;  //Creates variables as floating numbers.
boolean digital2, digital3;        //Creates variables as boolean (HIGH or LOW, TRUE or FALSE)

void setup()
{                             //Setup. This section runs only once.
    Serial.begin(9600);       //Sets the communication speed between PC and Arduino Uno to 9600 baud.
    pinMode(2, INPUT);        //Sets the digital 2 pin to input mode (High impedance).
    pinMode(3, INPUT_PULLUP); //Sets the digital 2 pin to input mode with "Pull Up" (High impedance and Normal High).
    delay(500);               //0.5 seconds break.
} //end of setup

void loop()
{ //Loop. This section runs in an unending loop.
    //Collect data from all the inputs
    analog0 = analogRead(A0);  //Reads data from analog port 0 and stores it in the variable "analog0".
    analog1 = analogRead(A1);  //Reads data from analog port 1 and stores it in the variable "analog1".
    digital2 = digitalRead(2); //Reads data from digital port 2 and stores it in the variable "digital2".
    digital3 = digitalRead(3); //Reads data from digital port 3 and stores it in the variable "digital3".
    //Note the difference between pin numbering in analog (Ax) and digital (x).

    //Convertion from digital value to voltage value
    analog0_volt = ((float)analog0 / 1023) * 5; //Scales from 0-1023 (integers) to 0.0-5.0 (decimal numbers). 0=0V 1023=5V.
    analog1_volt = (analog1 / 1023.0) * 5;      //Does the same as the previous line. Notice the difference in the syntax.

    //Print out data to the monitor
    Serial.print(counter);         //Prints out the variable "counter".
    Serial.print("  - Analog0: "); //Prints the text inside the brackets "__".
    Serial.print(analog0_volt);    //Prints out the variable "analog0_volt".
    Serial.print("   Analog1: ");  //Prints the text.
    Serial.print(analog1_volt);    //Prints out the variable "analog1_volt".
    Serial.print("   Digital2: "); //Prints the text.
    Serial.print(digital2);        //Prints out the variable "digital2".
    Serial.print("   Digital3: "); //Prints the text.
    Serial.println(digital3);      //Prints out the variable "digital3" and ends with a line shift.

    delay(1000); //A 1000ms delay.
    counter++;   //Increments the variable "counter".

} //end of function (Returns to start of loop).

//The program inside the loop function will continue forever and ever, or until power down.

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