diff --git a/README.md b/README.md
index 5398ac034e394069c5a32cc569f80de11401c715..65dc508c14f67b1c2ec59882b28a803fe55773d1 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,9 @@
 ### Autowaveguide
 
-
 ```bash
 python -m venv env
 .\env\Scripts\activate
 pip install -r requirements.txt 
 ```
+
+The PID code is in `app/codes/mainwindow.py`.