diff --git a/ion/src/simulator/shared/main_sdl.cpp b/ion/src/simulator/shared/main_sdl.cpp
index 78c3fa00a..ac714addb 100644
--- a/ion/src/simulator/shared/main_sdl.cpp
+++ b/ion/src/simulator/shared/main_sdl.cpp
@@ -140,6 +140,7 @@ void refresh() {
   Display::draw(sRenderer, &screenRect);
 #endif
   SDL_RenderPresent(sRenderer);
+  sNeedsRefresh = false;
 
   IonSimulatorCallbackDidRefresh();
 }