diff --git a/cores/arduino/wiring.h b/cores/arduino/wiring.h
index df7c314..e6dcde1 100755
--- a/cores/arduino/wiring.h
+++ b/cores/arduino/wiring.h
@@ -32,10 +32,6 @@
 extern "C"{
 #endif
 
-#ifndef ARDUINO
-#define ARDUINO 18
-#endif
-
 #define HIGH 0x1
 #define LOW  0x0