diff --git a/src/Arduino_GigaDisplay_GFX.h b/src/Arduino_GigaDisplay_GFX.h
index a2bff6b..e1bb266 100644
--- a/src/Arduino_GigaDisplay_GFX.h
+++ b/src/Arduino_GigaDisplay_GFX.h
@@ -7,6 +7,7 @@
 #include "Adafruit_SPITFT.h"
 #include "dsi.h"
 #include "SDRAM.h"
+#include "rtos.h"
 
 class GigaDisplay_GFX : public Adafruit_GFX {
   public:
@@ -50,4 +51,4 @@ class GigaDisplay_GFX : public Adafruit_GFX {
     rtos::Thread* _refresh_thd;
 };
 
-#endif //__ARDUINO_GIGADISPLAY_GFX__
\ No newline at end of file
+#endif //__ARDUINO_GIGADISPLAY_GFX__