15. interface and application programming

MIT app inventor

For this weeks assigment i want to try MIT app inventor since it is the firt time i used this I started with a tuturial i found online before making something of my own.

tutorial

I wnated to make an app to change the colour of a RGB led because mayby I can implemet this in my final project. I followed this tutorial

setting up the app enviroment

IT works very user friendly you can click draw all the components to the right place.

When the enviroment is ready i started with the code behind everything.

building the electronic part

• Arduino UNO
• Bluetooth module HC-05
• RGB LED
• 3 x 220Ohm resistor
• Breadboard
• Jumper wires

installing the app on the phone

could connect with the bluethooth module on the bradboard and could change the colour af the led therefore I had the program the arduino with the following code i got from the instructable.

/*
 * Rui Santos 
 * Complete Project Details https://randomnerdtutorials.com
 */

#define max_char 12
char message[max_char];    // stores you message
char r_char;               // reads each character
byte index = 0;            // defines the position into your array
int i;

int redPin = 11;     // Red RGB pin -> D11
int greenPin = 10;   // Green RGB pin -> D10
int bluePin = 9;     // Blue RGB pin -> D9

int redValue = 255;     // Red RGB pin -> D11
int greenValue = 255;   // Green RGB pin -> D10
int blueValue = 255;     // Blue RGB pin -> D9

String redTempValue;     // Red RGB pin -> D11
String greenTempValue;   // Green RGB pin -> D10
String blueTempValue;     // Blue RGB pin -> D9

int flag = 0;
char currentColor;  

void setup() {
  pinMode(redPin,OUTPUT);
  pinMode(bluePin,OUTPUT);
  pinMode(greenPin, OUTPUT);
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
}

void loop() {
  //while is reading the message 
  while(Serial.available() > 0){
    flag = 0;
    //the message can have up to 12 characters 
    if(index < (max_char-1)){         
      r_char = Serial.read();      // Reads a character
      message[index] = r_char;     // Stores the character in message array
      if(r_char=='R'){
         currentColor = 'R';
         redTempValue = "";
      }
      else if(r_char=='G'){
         currentColor = 'G';
         greenTempValue = "";
      }
      else if(r_char=='B'){
         currentColor = 'B';
         blueTempValue = "";
      }
      if(currentColor == 'R' && r_char!='R'){
         redTempValue += r_char;
      }
      else if(currentColor == 'G' && r_char!='G'){
         greenTempValue += r_char;
      }
      else if(currentColor == 'B' && r_char!='B'){
         blueTempValue += r_char;
      }
      index++;                     // Increment position
      message[index] = '\0';       // Delete the last position
   }

 }

 if(flag == 0){
   analogWrite(redPin, 255-redTempValue.toInt());
   analogWrite(greenPin, 255-greenTempValue.toInt());
   analogWrite(bluePin, 255-blueTempValue.toInt());
   /*Serial.print('R');
   Serial.println(redTempValue);
   Serial.print('G');
   Serial.println(greenTempValue);
   Serial.print('B');
   Serial.println(blueTempValue);
   Serial.print("MESSAGE ");*/
   Serial.println(message);
   flag=1;
       for(i=0; i<12; i++){
      message[i] = '\0';
    } 
    //resests the index
    index=0;  
 }

}

making a game.

After testing the first tutorial I followed an extra lessons in the lab about app inventor. The teacher helped me with making the game wack-a-moll.

### link the the group assigment

interface

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Last update: July 10, 2021