Fibonacci led

fibonacci_led.ino

void setup() {
asm volatile(R"(
  ldi r16, 0b00001000
  out 0x17, r16
  ldi r19, 0
  ldi r20, 1
  ldi r21, 1
task1:
  ldi r16, 0b00001000 
  out 0x18, r16 
  rcall delay_short0  
  ldi r16, 0b00000000 
  out 0x18, r16
  rcall delay_short0
  dec r21
  brne task1
  rcall fib
  rcall delay0
  rjmp task1

delay0:
  ldi r17, 0  
delay1: 
  ldi r18, 0
delay2: 
  dec r18 
  brne delay2 
  dec r17 
  brne delay1
  ret

delay_short0:
  ldi r17, 0
delay_short1:
  ldi r18, 128
delay_short2:
  dec r18 
  brne delay_short2 
  dec r17
  brne delay_short1
  ret
  
fib:
  mov r21, r20
  add r20, r19
  mov r19, r21
  mov r21, r20
  ret
)");
}

void loop() {
}