P5 initial

Abgaben/P4/keys.c

@@ -0,0 +1,34 @@
+#include "keys.h"
+
+void setupTimer0() {
+	// Configure Timer0 for CTC mode
+	TCCR0A |= (1 << WGM01);                 // Set Waveform Generation Mode bits for CTC
+	TCCR0B |= (1 << CS01) | (1 << CS00);    // Set prescaler to 64
+	OCR0A = 249;                            // Set Output Compare Register to 249 for ~1ms interrupt
+	TIMSK0 |= (1 << OCIE0A);                // Enable Timer0 Output Compare A Match interrupt
+}
+
+void setupRegisters(){
+		DDRD = 0xff;										// Data direction register D (D0 -> D6) as output
+		// PORTD = 0xff;									// setting bit for 7-segment show 0
+		// => spielt keine Rolle, wird von der while Schleife <20>bernommen
+		
+		DDRB = 0x01;										// Data direction register B (B0) as output and DDRB (B1, B2) as input
+		PORTB |= (1 << PINB1) | (1 << PINB2) ;				// setting bit for teens B0=0 and SW1-2
+		// PINB=0 => start with LED3 (Einer)
+		
+		// mit unserem Atmega nicht m<>glich, da keine PCINT8_vect und PCINT9_vect vorhanden
+		// DDRC = 0x00;										// Data direction register C as input for SW1 and SW2
+		// PORTC |= (1<<PINC0) | (1<<PINC1);					// settings pins for SW1 -> PINC0 and SW2 -> PINC1
+		
+		cli();												// clear global interrupt flag: interrupts will be immediately disabled
+		PCICR |= 0x01;										// Pin Change Interrupt Control Register: turn on PortB
+		PCMSK0 |= (1 << PINB1) | (1 << PINB2);				// trigger interrupt when SW1 or SW2 is pressed
+		sei();												// set global interrupt enable
+
+}
+
+void init(){
+	setupTimer0();
+	setupRegisters();
+}