diff --git a/3-99 Research/3 ARCADE/I2C/main.c b/3-99 Research/3 ARCADE/I2C/main.c
index 190ec38ee..8bc0530f6 100644
--- a/3-99 Research/3 ARCADE/I2C/main.c	
+++ b/3-99 Research/3 ARCADE/I2C/main.c	
@@ -1,16 +1,16 @@
-#include <avr/io.h>
+#include <avr/iom328p.h>
 #include <util/delay.h>
 
 // The main function: our program entry point
 int main(void) {
   // Set PB5 as output. DDRB is the data direction register for port B.
   // (1 << PB5) shifts 1 over by PB5 bits creating a bitmask.
-  DDRB |= (1 << PB5);
+  DDRB |= (1 << DDB5);
 
   // Infinite loop to blink the LED
   while (1) {
     // Set PB5 high: LED ON
-    PORTB |= (1 << PB5);
+    PORTB |= (1 << PORTB5B5);
     _delay_ms(100); // Delay 1000 milliseconds (1 second)
 
     // Clear PB5: LED OFF