added main() func testing for setup.

avr_usart.c

@@ -30,15 +30,14 @@ int main() {
     //enable interrupts
     sei();
     
-    unsigned char data[] = "AT+WAKE";
+    uint8_t buf_len = 12;
+    unsigned char data[12] = "HELLO WORLD\0";
+    
 
     while(1) {
+        serial0_write(data, buf_len);
         _delay_ms(1000);
-        //led_blink();
-        for(uint8_t i = 0; i < 7; i++) {
-            tx_usart0(data[i]);
-        }
-        
+         
     }
     
     return 0;