Create library for managing LED binary display

led.c

@@ -0,0 +1,77 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include "led.h"
+
+#define SET_LED(PORT, IDX, NUM) PORT = ((PORT & ~(1<<(IDX))) | (~(NUM) & 1<<(IDX)))
+
+volatile uint8_t led_hour;
+volatile uint8_t led_minute;
+volatile uint8_t led_second;
+
+void led_init(void) 
+{
+  // Set outputs
+  ANODES_DIR |= HOUR_ANODE | MINUTE_ANODE | SECOND_ANODE; 
+  LED0_DIR |= LED0; 
+  LED1_DIR |= LED1; 
+  LED2_DIR |= LED2; 
+  LED3_DIR |= LED3; 
+  LED4_DIR |= LED4; 
+  LED5_DIR |= LED5; 
+
+  // Clear LEDs
+  ANODES_PORT = HOUR_ANODE | MINUTE_ANODE | SECOND_ANODE;
+  LED0_PORT |= LED0;
+  LED1_PORT |= LED1;
+  LED2_PORT |= LED2;
+  LED3_PORT |= LED3;
+  LED4_PORT |= LED4;
+  LED5_PORT |= LED5;
+
+  TCCR0 |= (1<<WGM01); // CTC Mode
+  TCCR0 |= (1<<CS02) | (1<<CS00); // Prescaler 1024
+  OCR0 = 38; // 200Hz
+  TIMSK |= (1<<OCIE0); // Enable CTC interruptions
+}
+
+ISR(TIMER0_COMP_vect) 
+{
+  static uint8_t counter = 1;    
+
+  switch(counter) {
+    case 1: 
+      ANODES_PORT = ~HOUR_ANODE;
+      SET_LED(LED0_PORT, 0, led_hour);
+      SET_LED(LED1_PORT, 1, led_hour);
+      SET_LED(LED2_PORT, 2, led_hour);
+      SET_LED(LED3_PORT, 3, led_hour);
+      SET_LED(LED4_PORT, 4, led_hour);
+      SET_LED(LED5_PORT, 5, led_hour);
+      break;
+    case 2: 
+      ANODES_PORT = ~MINUTE_ANODE;
+      SET_LED(LED0_PORT, 0, led_minute);
+      SET_LED(LED1_PORT, 1, led_minute);
+      SET_LED(LED2_PORT, 2, led_minute);
+      SET_LED(LED3_PORT, 3, led_minute);
+      SET_LED(LED4_PORT, 4, led_minute);
+      SET_LED(LED5_PORT, 5, led_minute);
+      break;
+    case 4: 
+      ANODES_PORT = ~SECOND_ANODE;
+      SET_LED(LED0_PORT, 0, led_second);
+      SET_LED(LED1_PORT, 1, led_second);
+      SET_LED(LED2_PORT, 2, led_second);
+      SET_LED(LED3_PORT, 3, led_second);
+      SET_LED(LED4_PORT, 4, led_second);
+      SET_LED(LED5_PORT, 5, led_second);
+      break;
+  }
+
+  counter <<= 1;
+
+  if(counter > 4) 
+  {
+    counter = 1;        
+  }
+}

led.h

@@ -0,0 +1,35 @@
+#ifndef __LED_H__
+#define __LED_H__
+
+#define LED0_PORT PORTA
+#define LED0_DIR DDRA
+#define LED0 (1<<0)
+#define LED1_PORT PORTA
+#define LED1_DIR DDRA
+#define LED1 (1<<1)
+#define LED2_PORT PORTA
+#define LED2_DIR DDRA
+#define LED2 (1<<2)
+#define LED3_PORT PORTA
+#define LED3_DIR DDRA
+#define LED3 (1<<3)
+#define LED4_PORT PORTA
+#define LED4_DIR DDRA
+#define LED4 (1<<4)
+#define LED5_PORT PORTA
+#define LED5_DIR DDRA
+#define LED5 (1<<5)
+
+#define ANODES_PORT PORTD
+#define ANODES_DIR DDRD
+#define HOUR_ANODE (1<<PD5)
+#define MINUTE_ANODE (1<<PD6)
+#define SECOND_ANODE (1<<PD7)
+
+extern volatile uint8_t led_hour;
+extern volatile uint8_t led_minute;
+extern volatile uint8_t led_second;
+
+void led_init(void);
+
+#endif

main.c

@@ -0,0 +1,19 @@
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include "led.h"
+
+int main() 
+{
+  led_init();
+
+  sei();
+
+  led_hour = 0;
+  led_minute = 0;
+  led_second = 0;
+
+  while(1) 
+  {
+
+  }
+}