[ES] Added 3.3

Signed-óff-by: Jim Martens <github@2martens.de>

es/blatt3/CMakeLists.txt

@@ -10,3 +10,8 @@ generate_arduino_firmware(uebung3-2
     SKETCH uebung3-2
     PROGRAMMER usbtinyisp
     NO_AUTOLIBS)
+
+generate_arduino_firmware(uebung3-3
+    SKETCH uebung3-3
+    PROGRAMMER usbtinyisp
+    NO_AUTOLIBS)

es/blatt3/uebung3-3/uebung3-3.ino

@@ -0,0 +1,143 @@
+#include <Servo>
+
+// these variables describe the used hardware pins
+// adjust them when you use other pins
+// hardware pins
+int az = 50;
+
+int xout = A1;
+int zout = A3;
+int vref = A0;
+int ledPin = 13;
+
+// servo
+Servo ourServo;
+int servoPin = 11;
+
+// used to achieve a 10 Hz frequency
+// don't touch them
+long rc = 1049999;
+
+// flags for servo
+bool cwMaxReached = false;
+bool ccwMaxReached = false;
+bool lightLED = false;
+
+bool volatile read_ready = false;
+
+/**
+ * Calculates the servo position.
+ *
+ * @param int currentServoPos
+ * @param int rotationX
+ */
+int calculate_new_servo_pos(int currentServoPos, int rotationX) {
+    int newServoPos = currentServoPos;
+
+    if (!cwMaxReached && !ccwMaxReached) {
+        // clockwise rotation from 90 to 180
+        newServoPos = currentServoPos + rotationX;
+    }
+    else if (cwMaxReached && !ccwMaxReached) {
+        // counter clockwise rotation from 180 to 0
+        newServoPos = currentServoPos - rotationX;
+    }
+    else if (cwMaxReached && ccwMaxReached) {
+        // clockwise rotation from 0 to 90
+        newServoPos = currentServoPos + rotationX;
+        if (newServoPos >= 90) {
+            cwMaxReached = false;
+            ccwMaxReached = false;
+        }
+    }
+
+    if (newServoPos > 180) {
+        newServoPos = 180;
+        cwMaxReached = true;
+        lightLED = true;
+    }
+
+    if (newServoPos < 0) {
+        newServoPos = 0;
+        ccwMaxReached = true;
+        lightLED = true;
+    }
+
+    return newServoPos;
+}
+
+/**
+ * Setup function for initial setup code
+ */
+void setup() {
+    pmc_set_writeprotect(false);
+    pmc_enable_periph_clk(ID_TC1);
+
+    // configure hardware timer
+    TC_Configure(TC1, 0, TC_CMR_WAVE | TC_CMR_WAVSEL_UP_RC | TC_CMR_TCCLKS_TIMER_CLOCK2) ;
+    TC_SetRC(TC1, 0, rc);
+
+    TC1->TC_CHANNEL[0].TC_IER=TC_IER_CPCS;   // IER = interrupt enable register
+    TC1->TC_CHANNEL[0].TC_IDR=~TC_IER_CPCS;
+
+    NVIC_ClearPendingIRQ(TC1_IRQn);
+    NVIC_EnableIRQ(TC1_IRQn);
+
+    // start hardware timer
+    TC_Start(TC1, 0);
+
+    // Configure pins
+    pinMode(ledPin, OUTPUT);
+    pinMode(az, OUTPUT);
+    digitalWrite(az, HIGH);
+    digitalWrite(ledPin, LOW);
+    
+    ourServo.attach(servoPin);
+    ourServo.write(90);
+
+    // initialize serial port
+    Serial.begin(9600);
+}
+
+/**
+ * Loop function for main code
+ */
+void loop() {
+    if (read_ready) {
+        int xAxis = analogRead(xout);
+        int ref = analogRead(vref);
+
+        double differenceXRef = xAxis - ref;
+        double rotationX = differenceXRef / 9.1;
+
+        int currentServoPos = ourServo.read();
+        int newServoPos = calculate_new_servo_pos(currentServoPos, rotationX);
+
+        if (lightLED) {
+            digitalWrite(ledPin, HIGH);
+            delay(10);
+            digitalWrite(ledPin, LOW);
+            delay(10);
+            digitalWrite(ledPin, HIGH);
+            delay(10);
+            digitalWrite(ledPin, LOW);
+            delay(10);
+            digitalWrite(ledPin, HIGH);
+            delay(10);
+            digitalWrite(ledPin, LOW);
+            lightLED = false;
+        }
+        ourServo.write(newServoPos);
+        read_ready = false;
+    }
+}
+
+/**
+ * Used to handle the timer.
+ */
+void TC1_Handler()
+{
+    // request static for some magic behind the curtain
+    TC_GetStatus(TC1, 0);
+    read_ready = true;
+}