diff --git a/IOSTM.cpp b/IOSTM.cpp
index 8082cfb..e2f9b00 100644
--- a/IOSTM.cpp
+++ b/IOSTM.cpp
@@ -764,9 +764,16 @@ void CIO::setP25Int(bool on)
 #endif
 }
 
+// Simple delay function for STM32
+// Example from: http://thehackerworkshop.com/?p=1209
 void CIO::delayInt(unsigned int dly)
 {
-  unsigned int loopsPerMillisecond = (SystemCoreClock/1000) / 3; //3 clock cycles per loop
+#if defined(STM32F7_NUCLEO)
+  unsigned int loopsPerMillisecond = (SystemCoreClock/1000);
+#else
+  unsigned int loopsPerMillisecond = (SystemCoreClock/1000) / 3;
+#endif
+
   for (; dly > 0; dly--)
   {
     asm volatile //this routine waits (approximately) one millisecond