diff --git a/Code/README.md b/Code/README.md
index 4ea6aa18..929b8dd5 100644
--- a/Code/README.md
+++ b/Code/README.md
@@ -13,3 +13,8 @@ Very similar to the HanDebugger, simply reading the HAN data and outputting the
 
 ![ESPCircuit](./ESPDebugger/Circuit%20(breadboard).jpg)
 ![ESPScreenshot](./ESPDebugger/screenshot.png)
+
+### SerialTestPattern (Arduino sketch, any variant)
+This code outputs a changing serial test pattern.
+
+![](SerialTestPattern.gif)
diff --git a/Code/SerialTestPattern.gif b/Code/SerialTestPattern.gif
new file mode 100644
index 00000000..6429c1be
Binary files /dev/null and b/Code/SerialTestPattern.gif differ