added arduino style pins, and baseline functionality

Author: cristidragomir97

examples/LoveButton/LoveButton.ino

@@ -4,8 +4,15 @@ CapacitiveTouch touchButton = CapacitiveTouch(LOVE_BUTTON);
 
 void setup() {
   Serial.begin(9600);
-  touchButton.begin();
-  touchButton.setThreshold(9000);
+  
+  if(touchButton.begin()){
+    Serial.println("Capacitive touch sensor initialized.");
+  } else {
+    Serial.println("Failed to initialize capacitive touch sensor. Please use a supported pin.");
+    while(true);
+  }
+
+  touchButton.setThreshold(2000);
 }
 
 void loop() {
@@ -16,7 +23,7 @@ void loop() {
 
   // Check if the sensor is touched (raw value exceeds the threshold).
   if (touchButton.isTouched()) {
-    Serial.println("D1 touched!");
+    Serial.println("Button touched!");
   }
 
   delay(100);

src/CapacitiveTouch.cpp

@@ -177,17 +177,17 @@ void initDTC() {
 // Non-Template Class Member Functions
 // ------------------------------
 
-CapacitiveTouch::CapacitiveTouch(uint8_t pin) : _pin(pin), _threshold(500), _sensorIndex(0) {
-  CapTouchPinMapping mapping;
-  if (lookupMapping(pin, mapping)) {
-    _ts_num   = mapping.ts_num;
-    _chac_idx = mapping.chac_idx;
-    _chac_val = mapping.chac_val;
-  } else {
-    // If unsupported, set values to 0 (error handling; you may choose to report an error)
-    _ts_num = 0;
-    _chac_idx = 0;
-    _chac_val = 0;
+/**
+ * @brief Construct with the Arduino-side pin number (e.g. D4, A1, LOVE_BUTTON).
+ * @param pin Arduino pin (0..20 on Minima, 0..27 on WiFi).
+ */
+CapacitiveTouch::CapacitiveTouch(uint8_t pin)
+  : _pin(pin), _mappingIndex(0xFF), _threshold(500), _baseline(0), _sensorIndex(0)
+{
+  _mappingIndex = findMappingIndex(pin);
+  if (_mappingIndex != 0xFF) {
+    auto &m = capTouchMappings[_mappingIndex];
+    // stash ts_num/chac_idx/chac_val if you need them—but you can also defer that until begin()
   }
 }
 
@@ -202,27 +202,44 @@ bool CapacitiveTouch::lookupMapping(uint8_t pin, CapTouchPinMapping &mapping) {
   return false;
 }
 
-void CapacitiveTouch::begin() {
+bool CapacitiveTouch::begin() {
+  if (_mappingIndex == 0xFF) {
+    return false;
+  }
   pinMode(_pin, INPUT);
   initCTSU();
   if (!setTouchMode(_pin)) {
-    Serial.println("Error: Failed to enable touch mode on this pin.");
-    return;
+    return false;
   }
   _sensorIndex = pinToDataIndex[_pin];
-  Serial.println("CapacitiveTouch sensor initialized.");
+
+  long sum = 0;
+  for (int i = 0; i < CALIBRATION_SAMPLES; i++) {
+    sum += readRaw();
+    delay(5);
+  }
+  _baseline = sum / CALIBRATION_SAMPLES;
+  return true;
+}
+
+int CapacitiveTouch::readRaw() {
+    startTouchMeasurement(false);
+    while (!touchMeasurementReady()) {
+      delay(1);
+    }
+    return results[_sensorIndex][0];
 }
 
 int CapacitiveTouch::read() {
-  startTouchMeasurement(false);
-  while (!touchMeasurementReady()) {
-    delay(1);
-  }
-  return results[_sensorIndex][0];
+    int raw   = readRaw();
+    int delta = raw - _baseline;
+    return (delta > 0) ? delta : 0;
 }
 
 bool CapacitiveTouch::isTouched() {
-  return read() > _threshold;
+    int delta = read();
+    return (delta >  _threshold) ||
+           (delta < -_threshold);
 }
 
 void CapacitiveTouch::setThreshold(int threshold) {

src/CapacitiveTouch.h

@@ -15,6 +15,8 @@
 // Define a symbolic constant for the LOVE button (special pin).
 #define LOVE_BUTTON   20  
 
+#define CALIBRATION_SAMPLES 16 ///< Number of samples for calibration.
+
 /**
  * @struct CapTouchPinMapping
  * @brief Defines the mapping between an Arduino pin and its capacitive touch hardware settings.
@@ -106,7 +108,7 @@ class CapacitiveTouch {
      *
      * Configures the pin and initializes the CTSU/DTC hardware.
      */
-    void begin();
+    bool begin();
 
     /**
      * @brief Reads the raw sensor value.
@@ -143,18 +145,31 @@ class CapacitiveTouch {
     uint8_t _chac_idx;  ///< Channel control index (from mapping).
     uint8_t _chac_val;  ///< Bit mask (from mapping).
     uint8_t _sensorIndex; ///< Index assigned after enabling the channel.
+    uint8_t _mappingIndex; ///< Index in the mapping array.
+    int     _baseline;  
+
     /**
      * @brief Looks up the mapping for a given pin.
      * @param pin The Arduino pin.
      * @param mapping Reference to a mapping structure to fill.
      * @return true if mapping found and supported, false otherwise.
      */
     bool lookupMapping(uint8_t pin, CapTouchPinMapping &mapping);
+    int readRaw();
 
        // Low-level helper functions as static members
     static bool setTouchMode(uint8_t pin);
     static void startTouchMeasurement(bool fr);
     static bool touchMeasurementReady();
+
+    static uint8_t findMappingIndex(uint8_t pin) {
+    for (uint8_t i = 0; i < (sizeof(capTouchMappings)/sizeof(capTouchMappings[0])); i++) {
+      if (capTouchMappings[i].arduinoPin == pin) {
+        return i;
+      }
+    }
+    return 0xFF;
+  }
 };
 
 #endif // CAPACITIVE_TOUCH_H