diff --git a/docs/configuration/module-config/serial.mdx b/docs/configuration/module-config/serial.mdx
index 5f14d8e5..a507ec5f 100644
--- a/docs/configuration/module-config/serial.mdx
+++ b/docs/configuration/module-config/serial.mdx
@@ -265,7 +265,7 @@ while True:
 
 #### Arduino Mini Pro Code
 
-
+```cpp
 int LED = 13; // the pin to which the LED is connected
 int PIR = 2;  // the pin to which the sensor is connected
 int previousState = LOW; // previous state of the sensor