Async Keyboard implementation

Readme.md

@@ -0,0 +1,13 @@
+# Documentation 
+## 1.0 Keypad
+The kepad is driven by an io-expander. Thus it can be acessed over i2c.
+Adress 0x21
+### 1.1 Wiring
+* Red: 3.3V
+* Black GND
+* Green SDA -> D3
+* Grey SCL -> D4  
+
+## 2.0 LCD
+The LCD display is driven on the same i2c bus as the keypad.
+

platformio.ini

@@ -15,3 +15,4 @@ framework = arduino
 lib_deps = 
 	xreef/PCF8574 library@^2.2.1
 	marcoschwartz/LiquidCrystal_I2C@^1.1.4
+	miguelbalboa/MFRC522@^1.4.9

src/Keyboard.cpp

@@ -1,14 +1,14 @@
 #include "Keyboard.h"
-//#define DEBUG
+#define DEBUG
 #define PIN_WIRE_SDA D3
 #define PIN_WIRE_SCL D4
-Keyboard::Keyboard(uint8_t debounce)
+Keyboard::Keyboard(uint8_t _debounce)
 {
-    this->debounce = debounce;
+    this->_debounce = _debounce;
 }
 void Keyboard::begin(TwoWire *databus)
 {
-    pcf8574 = new PCF8574(databus, 0x27, PIN_WIRE_SDA, PIN_WIRE_SCL);
+    pcf8574 = new PCF8574(databus, 0x21, PIN_WIRE_SDA, PIN_WIRE_SCL);
     pcf8574->pinMode(0, OUTPUT);
     for (int i = 1; i < 8; i++)
     {
@@ -35,12 +35,13 @@ Keyboard::~Keyboard()
 }
 void Keyboard::scan()
 {
-    if (millis() < timeElapsed + this->debounce)
+    if (millis() < _timeElapsed + this->_debounce)
-        return 0;
+        return;
     uint8_t key = 0;
     for (int i = 7; i > 4; i--) // Columns
     {
         pcf8574->digitalWrite(i, LOW);
+        delay(15);
         for (int j = 1; j < 5; j++)
         { // Rows
             key++;
@@ -51,14 +52,73 @@ void Keyboard::scan()
 #endif
             if (val == 0)
             {
-                timeElapsed = millis();
+                _timeElapsed = millis();
-                this->lastKey = key;
+                this->_lastKey = key;
-                this->buffer.push(mapChr(key));
+                this->_buffer.push_back(mapChr(key));
+                pcf8574->digitalWrite(i, HIGH);
+                return;
             }
         }
         pcf8574->digitalWrite(i, HIGH);
     }
 }
+void Keyboard::scanAsync()
+{
+    /** Without delay - scanning only one column per cycle **/
+    if (millis() < _timeElapsed + this->_debounce)
+        return;
+    uint8_t key = 0;
+    switch (_current_scan_col)
+    {
+        default:
+            pcf8574->digitalWrite(7, LOW);
+            _current_scan_col = 1;
+            break;
+        case 1:
+        {
+            scanColumn(&key, 1, 4);
+            pcf8574->digitalWrite(6, LOW);            
+            pcf8574->digitalWrite(7, HIGH);
+            _current_scan_col = 2;
+            break;
+        }
+        case 2:
+        {
+            key=4;
+            scanColumn(&key, 1, 4);
+            pcf8574->digitalWrite(5, LOW);            
+            pcf8574->digitalWrite(6, HIGH);
+            _current_scan_col = 3;
+            break;
+        }
+        case 3:
+        {
+            key=8;
+            scanColumn(&key, 1, 4);
+            pcf8574->digitalWrite(7, LOW);            
+            pcf8574->digitalWrite(5, HIGH);
+            _current_scan_col = 1;
+            break;
+        }
+        break;
+    }
+}
+
+void Keyboard::scanColumn(uint8_t* key_ptr, uint8_t start, uint8_t stop){
+    for (int j = start; j <= stop; j++)
+            { // Rows
+                (*key_ptr)++;
+                uint8_t val = pcf8574->digitalRead(j);
+                if (val == 0)
+                {
+                    _timeElapsed = millis();
+                    this->_lastKey = *key_ptr;
+                    this->_buffer.push_back(mapChr(*key_ptr));
+                    Serial.print(*key_ptr);
+                    return;
+                }
+            }
+}
 char Keyboard::mapChr(uint8_t key)
 {
 
@@ -73,9 +133,9 @@ char Keyboard::mapChr(uint8_t key)
     case 4:
         return 'O';
     case 5:
-        return '5';
+        return '2';
     case 6:
-        return '1';
+        return '5';
     case 7:
         return '8';
     case 8:
@@ -93,11 +153,26 @@ char Keyboard::mapChr(uint8_t key)
         return 'F';
     }
 }
-char Keyboard::getChr()
+char Keyboard::getLastChr()
 {
-    return this->getChr(this->lastKey);
+    return this->mapChr(this->_lastKey);
 }
 
-bool Keyboard::available(){
+bool Keyboard::available()
-    return (!this->buffer.empty());
+{
+    return (!this->_buffer.empty());
+}
+void Keyboard::clear()
+{
+    this->_buffer.clear();
+}
+String Keyboard::getString()
+{
+    String out;
+    for (auto &&i : this->_buffer)
+    {
+        out.concat(i);
+    }
+    this->_buffer.clear();
+    return out;
 }

src/Keyboard.h

@@ -5,19 +5,24 @@
 class Keyboard
 {
 private:
-    unsigned long timeElapsed;
+    unsigned long _timeElapsed;
-    std::queue<char> buffer;
+    std::deque<char> _buffer;
-    uint8_t debounce;
+    uint8_t _debounce;
     PCF8574* pcf8574;
-    int lastKey;
+    uint8_t _lastKey;
+    uint8_t _current_scan_col;
+    void scanColumn(uint8_t *key, uint8_t start, uint8_t stop);
     /* data */
 public:
     Keyboard(uint8_t debounce);
     ~Keyboard();
     void scan();
+    void scanAsync();
     void begin(TwoWire *databus);
-    static char getChr(uint8_t key);
+    static char mapChr(uint8_t key);
-    char getChr();
+    char getLastChr();
     bool available();
+    void clear();
+    String getString();
 };
 #endif

src/Rfid.cpp

@@ -0,0 +1,9 @@
+#include "Rfid.h"
+
+Rfid::Rfid(/* args */)
+{
+}
+
+Rfid::~Rfid()
+{
+}

src/Rfid.h

@@ -0,0 +1,8 @@
+class Rfid
+{
+private:
+    /* data */
+public:
+    Rfid(/* args */);
+    ~Rfid();
+};

src/main.cpp

@@ -2,25 +2,179 @@
 #include <Arduino.h>
 #include <Wire.h>
 #include "Keyboard.h"
+#include <SPI.h>
+#include <MFRC522.h>
 
+// RFID Reader
+#define SS_PIN D8
+#define RST_PIN D1
+#define RFID_TIMEOUT 3000
+MFRC522 mfrc522(SS_PIN); // Create MFRC522 instance
+MFRC522::MIFARE_Key key;
+String rfid = "";
+String lastRfid = "";
+unsigned long lastRfidScan = 0;
+// i2C Bus
 #define PIN_WIRE_SDA D3
 #define PIN_WIRE_SCL D4
 #include <LiquidCrystal_I2C.h>
-TwoWire databus;
 Keyboard keyboard(200);
+LiquidCrystal_I2C lcd(0x27, 20, 4);
+int display_state = 0;
+String pin;
+unsigned long lastDisplayUpdate = 0;
+unsigned long displayTimer1 = 0;
+bool displayUpdate = true;
 void setup()
 {
 	Serial.begin(9600);
 	Serial.print("Starting");
 	delay(500);
-	keyboard.begin(&databus);
+	keyboard.begin(&Wire);
+
+	// LCD
+	lcd.init();
+	lcd.backlight();
+
+	// RFID
+	SPI.begin();
+	SPI.setClockDivider(SPI_CLOCK_DIV8);
+	mfrc522.PCD_Init();
+	mfrc522.PCD_SetAntennaGain(mfrc522.RxGain_max);
 }
 
+namespace states
+{
+	enum screenstates
+	{
+		MAIN,
+		ENTER_PIN_START,
+		ENTER_PIN_ADD_NUM,
+		VALIDATE_PIN,
+		ABORT,
+		DELAY,
+		READ_RFID
 
-
+	};
+}
 void loop()
 {
-	char key = keyboard.getKey();
+	keyboard.scanAsync();
-	if(key!=0)
+
-		Serial.println("Key " + String(key) +  "was pressed");
+	if (mfrc522.PICC_IsNewCardPresent() && mfrc522.PICC_ReadCardSerial())
+	{
+		rfid = "";
+		for (byte i = 0; i < mfrc522.uid.size; i++)
+		{
+			rfid += mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ";
+			rfid += String(mfrc522.uid.uidByte[i], HEX);
+		}
+		rfid.trim();
+		rfid.toUpperCase();
+		if (rfid != lastRfid || millis() > lastRfidScan + RFID_TIMEOUT)
+		{
+
+			display_state = states::READ_RFID;
+			displayUpdate = true;
+			Serial.print(rfid);
+			lastRfid = rfid;
+			lastRfidScan = millis();
+		}
+	}
+	if (keyboard.available())
+	{
+		if (keyboard.getLastChr() == 'X')
+		{
+			keyboard.clear();
+			display_state = states::ABORT;
+			displayUpdate = true;
+		}
+		else if (('0' <= keyboard.getLastChr()) && (keyboard.getLastChr() <= '9'))
+		{
+			Serial.print(keyboard.getLastChr());
+			if (display_state == states::ENTER_PIN_START)
+				display_state = states::ENTER_PIN_ADD_NUM;
+			else if (display_state != states::ENTER_PIN_ADD_NUM)
+				display_state = states::ENTER_PIN_START;
+			displayUpdate = true;
+		}
+		else if (keyboard.getLastChr() == 'O' && (display_state == 2 || display_state == 1))
+		{
+			keyboard.clear();
+			display_state = states::VALIDATE_PIN;
+			displayUpdate = true;
+		}
+	}
+	if (displayUpdate)
+	{
+		switch (display_state)
+		{
+		case states::MAIN:
+			lcd.setCursor(0, 0);
+			lcd.print("Welcome!");
+			lcd.setCursor(0, 1);
+			lcd.print("Enter Pin / Card");
+			displayUpdate = false;
+			break;
+		case states::ENTER_PIN_START: // Starting Pin
+			pin.clear();
+			lcd.clear();
+			lcd.print("Please enter Pin");
+			lcd.setCursor(0, 1);
+			pin.concat(keyboard.getString());
+			lcd.print("Pin: " + pin);
+			display_state = 2;
+			displayUpdate = false;
+			break;
+		case states::ENTER_PIN_ADD_NUM:
+		{
+			String input = keyboard.getString();
+			pin.concat(input);
+			lcd.print(input);
+			displayUpdate = false;
+			break;
+		}
+		case states::VALIDATE_PIN:
+			lcd.clear();
+			lcd.setCursor(0, 0);
+			lcd.print("Validating PIN");
+			lcd.setCursor(0, 1);
+			if (pin == "2626")
+				lcd.print("Accepted!");
+			else
+				lcd.print("Acess denied!");
+			pin.clear();
+			displayTimer1 = millis() + 3000;
+			display_state = states::DELAY;
+			break;
+		case states::ABORT:
+			lcd.clear();
+			lcd.print("Input aborted!");
+			displayTimer1 = millis() + 3000;
+			display_state = states::DELAY;
+			break;
+		case states::DELAY: // Delay
+			if (displayTimer1 != 0 && displayTimer1 < millis())
+			{
+				lcd.clear();
+				display_state = states::MAIN;
+			}
+			break;
+		case states::READ_RFID:
+		{
+			lcd.clear();
+			lcd.print("Card detected.");
+			lcd.setCursor(0, 1);
+
+			lcd.print(rfid);
+			displayTimer1 = millis() + 3000;
+			display_state = states::DELAY;
+			break;
+		}
+		default:
+			break;
+		}
+	}
+	//String input = keyboard.getString();
+	//Serial.println("Key " + input +  "was pressed");
 }