diff --git a/examples/ArduinoUniqueID/ArduinoUniqueID.ino b/examples/ArduinoUniqueID/ArduinoUniqueID.ino
index eb934a7..13b58a7 100644
--- a/examples/ArduinoUniqueID/ArduinoUniqueID.ino
+++ b/examples/ArduinoUniqueID/ArduinoUniqueID.ino
@@ -9,6 +9,7 @@
 void setup()
 {
 	Serial.begin(115200);
+	while(!Serial);
 	UniqueIDdump(Serial);
 	Serial.print("UniqueID: ");
 	for (size_t i = 0; i < UniqueIDsize; i++)
diff --git a/examples/ArduinoUniqueID8/ArduinoUniqueID8.ino b/examples/ArduinoUniqueID8/ArduinoUniqueID8.ino
index 90338a7..4bfcde8 100644
--- a/examples/ArduinoUniqueID8/ArduinoUniqueID8.ino
+++ b/examples/ArduinoUniqueID8/ArduinoUniqueID8.ino
@@ -9,6 +9,7 @@
 void setup()
 {
 	Serial.begin(115200);
+	while(!Serial);
 	UniqueID8dump(Serial);
 	Serial.print("UniqueID: ");
 	for (size_t i = 0; i < 8; i++)