Update README.md

stop-pattern · web-flow · commit 0690a93d7616 · 2024-09-27T00:41:07.000+09:00
diff --git a/README.md b/README.md
@@ -26,6 +26,9 @@
 
 
 ## 使い方
+### シリアル通信の仕様
+[spreadsheet](https://docs.google.com/spreadsheets/d/1ScX5CCfMGIy2SJhocsE9RfQSSqe-My4DV7IYqSuNI9Q/edit?usp=sharing)
+
 
 ## ライセンス
 - [MIT](LICENSE)
