diff --git a/IOSTM_CMSIS.cpp b/IOSTM_CMSIS.cpp
index ce498d4d..00f9767a 100644
--- a/IOSTM_CMSIS.cpp
+++ b/IOSTM_CMSIS.cpp
@@ -1,7 +1,7 @@
 /*
  *   Copyright (C) 2016 by Jim McLaughlin KI6ZUM
  *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
- *   Copyright (C) 2017,2018 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2017,2018,2020 by Jonathan Naylor G4KLX
  *   Copyright (C) 2017 by Wojciech Krutnik N0CALL
  *
  *   This program is free software; you can redistribute it and/or modify
@@ -460,6 +460,14 @@ void CIO::setPOCSAGInt(bool on)
 #endif
 }
 
+void CIO::setFMInt(bool on)
+{
+#if defined(USE_ALTERNATE_FM_LEDS)
+  BB_DSTAR = !!on;
+  BB_YSF   = !!on;
+#endif
+}
+
 void CIO::delayInt(unsigned int dly)
 {
   delay(dly);