#include <avr/io.h>
#include <avr/interrupt.h>

// This sketch reads Nano pin 12 and mirrors it onto pin 13.
// I'm not sure even this will be fast enough to mirror WS2812 protocol.

int main(void) {
  cli();                    // disable interrupts during setup

  DDRB |= (1 << PB5);       // set PB5 as output pin (nano pin 13)
  DDRB &= ~(1 << DDB4);     // set PB4 as an input pin (nano pin 12)
  
  while (1) {
    PORTB = PINB << 1;
  }
}