#include ; SoftwareSerial mySerial(PB4, PB3); void setup() { // put your setup code here, to run once: mySerial.begin(9600); pinMode (PB0, OUTPUT); digitalWrite(PB0, 1); } void loop() { // put your main code here, to run repeatedly: if ( mySerial.available() > 0) { char d; char a = 'c'; d = mySerial.read(); if (d == a) { mySerial.println("RECIEVED"); digitalWrite(PB0, 0); delay(1); digitalWrite(PB0, 1); } } }