Payphone/Implementation


static const uint8_t D0 = 16; static const uint8_t D1 = 5; static const uint8_t D2 = 4; static const uint8_t D3 = 0; static const uint8_t D4 = 2; static const uint8_t D5 = 14; static const uint8_t D6 = 12; static const uint8_t D7 = 13; static const uint8_t D8 = 15;




const int rowPin0 = D0; //const int rowPin0 = 16; const int rowPin1 = D1; //const int rowPin1 = 5; const int rowPin2 = D2; //const int rowPin2 = 4;

const int rowPin3 = D3; //const int rowPin3 = 0; const int columnPin0 = D4; //const int columnPin0 = 2; const int columnPin1 = D5; //const int columnPin1 = 14; const int columnPin2 = D6; //const int columnPin2 = 12; const int strikePin = D7; //const int strikePin = 13; const int tonePin = D8; const int columns[] = { columnPin0, columnPin1, columnPin2 }; const int rows[] = { rowPin0, rowPin1, rowPin2, rowPin3 };

char keys[][12] = { "zero.", "one.", "two.", "three.", "four.", "five.", "six.", "seven.", "eight.", "nine.", "star.", "pound." }; // int tones[12] = { 1209, 1336, 1477 } int freq = 880;

const int matrix[4][3] =

 { 1, 2, 3, 
   4, 5, 6, 
   7, 8, 9, 
  10, 0, 11 };

const int rowIdentityMatrix[4][4] =

 { LOW, HIGH, HIGH, HIGH, 
 HIGH, LOW, HIGH, HIGH, 
 HIGH, HIGH, LOW, HIGH, 
 HIGH, HIGH, HIGH, LOW };

int canRegisterKeyPress[4][3] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 };

int pinCodeRingBuffer[4];

int currentPinIndex = 0;

void setup() {

 Serial.begin(115200);
 Serial.println("Hello World");

 resetPinCode();

 pinMode(strikePin, OUTPUT);
 pinMode(columnPin0, INPUT_PULLUP);
 pinMode(columnPin1, INPUT_PULLUP);
 pinMode(columnPin2, INPUT_PULLUP);

 pinMode(rowPin0, OUTPUT);
 pinMode(rowPin1, OUTPUT);
 pinMode(rowPin2, OUTPUT);
 pinMode(rowPin3, OUTPUT);

 digitalWrite(rowPin0, HIGH);
 digitalWrite(rowPin1, HIGH);
 digitalWrite(rowPin2, HIGH);
 digitalWrite(rowPin3, HIGH);

 digitalWrite(strikePin, LOW);

}

void loop() {

 gateKeep(getCurrentKey());

}

int getCurrentKey() {

 int currentPressedKey = -1;
 for (int r = 0; r < 4; r++) {
   for (int i = 0; i < 4; i++) {
     digitalWrite(rows[i], rowIdentityMatrix[r][i]);
   }
   delay(2);

   for (int c = 0; c < 3; c++) {
     const bool pressingKey = digitalRead(columns[c]) == LOW;
     if (pressingKey && canRegisterKeyPress[r][c]) {
       canRegisterKeyPress[r][c] = false;
       currentPressedKey = matrix[r][c];
       Serial.println(currentPressedKey);
       tone(tonePin, freq);
     } else if (!pressingKey) {
       canRegisterKeyPress[r][c] = true;
     }
     delay(2);
   }
 }

 return currentPressedKey;

}

void gateKeep(int key) {

 if (key >= 0) {
   Serial.println(key);
   updateRingBuffer(key);
   maybeStrikeIt();
   noTone(tonePin);
 }

}

void updateRingBuffer(int key) {

 pinCodeRingBuffer[currentPinIndex] = key;
 currentPinIndex = (currentPinIndex + 1) % 4;

}

void maybeStrikeIt() {

 //    const int code[] = { 1, 8, 4, 8 };
 const int code[] = { 2, 6, 0, 0 };
 // Check if the strike should strike out
 for (int i = 0; i < 4; i++) {
   bool isValidMatch = true;
   for (int j = 0; j < 4; j++) {
     if (pinCodeRingBuffer[(i + j) % 4] != code[j]) {
       isValidMatch = false;
       break;
     }
   }
   if (isValidMatch) {
     grantEntryAccess();
     break;
   }
 }

}

void grantEntryAccess() {

 Serial.println("Door is opening");
 reallyStrikeIt();

}

void reallyStrikeIt() {

 digitalWrite(strikePin, HIGH);
 delay(2500);
 digitalWrite(strikePin, LOW);
 for (int i = 0; i < 2; i++) {
   digitalWrite(strikePin, HIGH);
   delay(250);
   digitalWrite(strikePin, LOW);
   delay(250);
 }

 resetPinCode();

}

void resetPinCode() {

 pinCodeRingBuffer[0] =
   pinCodeRingBuffer[1] =
   pinCodeRingBuffer[2] =
   pinCodeRingBuffer[3] = 99;

}