uni/es/blatt3/uebung3-4/uebung3-4.ino

#include <Servo.h>

// these variables describe the used hardware pins
// adjust them when you use other pins
// hardware pins
int az = 50;

int xout = A4;
int zout = A2;
int vref = A3;
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 volatile cwMaxReached = false;
bool volatile ccwMaxReached = false;
bool volatile lightLED = false;

bool volatile read_ready = false;


/**
 * Calculates the servo position.
 *
 * @param int currentServoPos
 * @param int rotationZ
 */
int calculate_new_servo_pos(int currentServoPos, int rotationZ) {
    int newServoPos = currentServoPos + rotationZ;

    if (newServoPos > 159) {
        newServoPos = 159;
        cwMaxReached = true;
        lightLED = true;
    }

    if (newServoPos < 25) {
        newServoPos = 25;
        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(TC0, 1, TC_CMR_WAVE | TC_CMR_WAVSEL_UP_RC | TC_CMR_TCCLKS_TIMER_CLOCK2) ;
    TC_SetRC(TC0, 1, rc);

    TC0->TC_CHANNEL[1].TC_IER=TC_IER_CPCS;   // IER = interrupt enable register
    TC0->TC_CHANNEL[1].TC_IDR=~TC_IER_CPCS;

    NVIC_ClearPendingIRQ(TC1_IRQn);
    NVIC_EnableIRQ(TC1_IRQn);

    // start hardware timer
    //TC_Start(TC0, 1);

    // 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 (Serial.available() > 0) {
      char command[8];
      char currentChar;
      int i = 0;
      bool readable = true;
      while (readable) {
        currentChar = Serial.read();
        readable = (currentChar == -1);
        command[i] = currentChar;
        i++;
      }
      command[i] = '\0';
      
      if (strcmp(command, "LED_on") == 0) {
        digitalWrite(ledPin, HIGH);
      }
      else {
        digitalWrite(ledPin, LOW);
      }
      Serial.println(command);
    }
}

/**
 * Used to handle the timer.
 */
void TC1_Handler()
{
    // request static for some magic behind the curtain
    TC_GetStatus(TC0, 1);
    read_ready = true;
}