diff --git a/ArduinoLog.cpp b/ArduinoLog.cpp
index 4dba1aa..b66aa8b 100644
--- a/ArduinoLog.cpp
+++ b/ArduinoLog.cpp
@@ -169,6 +169,10 @@ void Logging::printFormat(const char format, va_list *args) {
 	{
 		_logOutput->print(va_arg(*args, long), DEC);
 	}
+	else if (format == 'u')
+	{
+		_logOutput->print(va_arg(*args, unsigned long), DEC);
+	}
 	else if (format == 'c')
 	{
 		_logOutput->print((char) va_arg(*args, int));