diff --git a/src/SerialReader.h b/src/SerialReader.h
index d661c95..d50f5cd 100644
--- a/src/SerialReader.h
+++ b/src/SerialReader.h
@@ -7,9 +7,9 @@ class SerialReader {
 	char buffer[bufferLength];
 
 public:
-    char* getBuffer() {
-        return buffer;
-    }
+	const char* getBuffer() {
+		return buffer;
+	}
 
 	int readLine(HardwareSerial &serial) {
 		static size_t pos = 0;