diff --git a/apple1.ino b/apple1.ino
index 902b1e5..ad9f8e0 100644
--- a/apple1.ino
+++ b/apple1.ino
@@ -4,6 +4,7 @@
 #include <SpiRAM.h>
 #include <UTFT.h>
 #include <r65emu.h>
+#include <r6502.h>
 
 #include "pia.h"
 #include "io.h"