Diff: touchbutton.cpp

Revision:

0:6ae7b9747a06

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/touchbutton.cpp	Wed Dec 01 03:28:28 2010 +0000
@@ -0,0 +1,97 @@
+#include "mbed.h"
+#include "touchbutton.h"
+#include "com.h"
+
+#ifdef DEBUGTOUCHLED
+DigitalOut debugled(LED1);
+#endif
+
+float TouchButton::difference() {
+    return previousValue - currentValue;
+}
+
+TouchButton::TouchButton(PinName ain, PinName din, PinName dout, float threshold, int debounceTime, char *nm) :   sensor(ain), charger(din), ground(dout) {
+
+    setThreshold(threshold);
+    setDebounceTime(debounceTime);
+    AnalogIn sensor(ain);
+    DigitalIn charger(din);
+    DigitalOut ground(dout);
+    ground.write(0);
+    timer.start();
+    sample();
+    storeValue();
+    strcpy(name,nm);
+#ifdef DEBUGTOUCH
+        com.printf("INIT BUTTON %s\r\n",name);
+#endif
+}
+
+void TouchButton::storeValue() {
+    previousValue=currentValue;
+}
+
+void TouchButton::setThreshold(float level) {
+    analogThreshold = level;
+}
+
+void TouchButton::setDebounceTime(int t) {
+    timeout_ms = t;
+}
+
+bool TouchButton::checkState() {
+    float diff;
+#ifdef DEBUGTOUCH
+        com.printf("CHECK BUTTON\r\n");
+#endif
+ 
+    charge();
+#ifdef DEBUGTOUCH
+        com.printf("CHARGE BUTTON\r\n");
+#endif    
+    sample();
+#ifdef DEBUGTOUCH
+        com.printf("CHARGE & SAMPLE BUTTON %s\r\n",name);
+        com.printf("Value:%3.2f\r\n", currentValue);
+#endif
+
+
+    diff=previousValue - currentValue;
+    storeValue();
+    if (diff > analogThreshold && timer.read_ms() > timeout_ms) {
+        timer.reset();
+#ifdef DEBUGTOUCH
+        com.printf("TOUCH %s\r\n", name);
+#endif
+#ifdef DEBUGTOUCHLED
+        //Toggle LED to show touch was registered
+        if (debugled.read()==1)
+            debugled=0;
+        else
+            debugled=1;
+#endif
+        return true;
+    } else {
+        return false;
+    }
+
+}
+
+float TouchButton::sample() {
+
+    float sum = 0;
+    for (int i=0; i<NUMSAMP;i++) {
+        float value = sensor.read();
+        sum = sum + value;
+    }
+    currentValue = sum/NUMSAMP;
+    return currentValue;
+
+}
+
+void TouchButton::charge() {
+    charger.mode(PullUp);
+    charger.mode(PullNone);
+    wait(.005);
+
+}