Sync LED blink behaviour to timer0

src/led.inc

@@ -0,0 +1,26 @@
+#define __SFR_OFFSET 0
+#include <avr/io.h>
+
+blink_led:
+    clr     r16                                         ; Clear register
+    out     TCNT0,      r16                             ; Reset Counter to 0
+    sbi     PORTB,      PB0                             ; Set LED on
+
+    ldi     r16,        (1<<OCF0A)
+    out     TIFR0,      r16                             ; Clear timer0 status
+
+    ldi     r16,        (1 << CS02) | (1 << CS00)       ; Load prescaler value (00000101 = prescaler 1024)
+    out     TCCR0B,     r16                             ; Enable clock source
+
+    ret
+
+blink_delay:
+    in      r16,        TIFR0                           ; Read Interrupt Flag Register
+    sbrs    r16,        OCF0A                           ; If OCF0A = 1 skip jump
+    rjmp    wait_loop                                   ; Else loopback
+
+    clr     r16                                         ; Cleanup register
+    out     TCCR0B, r16                                 ; Stop timer0 by clearing prescaler
+
+    cbi     PORTB, PB0                                  ; Set LED off
+    ret