[ES] Added blatt3

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

es/blatt3/uebung3-1-test/uebung3-1-test.ino

@@ -0,0 +1,77 @@
+// 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;
+
+// used to achieve a 10 Hz frequency
+// don't touch them
+int rc = 1049999;
+
+bool volatile read_ready = false;
+
+/**
+ * Setup function for initial setup code
+ */
+void setup() {
+  pmc_set_writeprotect(false);
+  pmc_enable_periph_clk(ID_TC0);
+
+  // configure hardware timer
+  TC_Configure(TC0, 0, TC_CMR_WAVE | TC_CMR_WAVSEL_UP_RC | TC_CMR_TCCLKS_TIMER_CLOCK2) ;
+  TC_SetRC(TC0, 0, rc);
+
+  TC0->TC_CHANNEL[0].TC_IER=TC_IER_CPCS;   // IER = interrupt enable register
+  TC0->TC_CHANNEL[0].TC_IDR=~TC_IER_CPCS;
+
+  NVIC_ClearPendingIRQ(TC0_IRQn);
+  NVIC_EnableIRQ(TC0_IRQn);
+
+  // start hardware timer
+  TC_Start(TC0, 0);
+
+  // Configure axis pins for input mode
+  pinMode(az, OUTPUT);
+  digitalWrite(az, HIGH);
+  
+  // initialize serial port
+  Serial.begin(9600);
+}
+
+/**
+ * Loop function for main code
+ */
+void loop() {
+  Serial.println("NOTHING HAPPENS");
+  /*if (read_ready) {
+    int xAxis = analogRead(xout);
+    int zAxis = analogRead(zout);
+    int ref = analogRead(vref);    
+  
+    int differenceXRef = xAxis - ref;
+    int differenceZRef = zAxis - ref;  
+  
+    Serial.print("x:");
+    Serial.println(xAxis);
+    Serial.print("z: ");
+    Serial.println(zAxis);
+    Serial.print("x - ref: ");
+    Serial.println(differenceXRef);
+    Serial.print("z - ref: ");
+    Serial.println(differenceZRef);
+    read_ready = false;    
+  }*/
+}
+
+/**
+ * Used to handle the timer.
+ */
+void TC0_Handler()
+{
+  // request static for some magic behind the curtain
+  TC_GetStatus(TC0, 0);
+  read_ready = true;
+}