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 # Timing diagram
 
-Draw timing diagram by root
\ No newline at end of file
+Easy python script to draw timing diagram by using pyroot.
+
+![example](/example.eps)
+
+## Requirement
+
+ - python3x
+ - pyroot
+ - pyyaml
+
+
+## Usage
+
+Edit yaml file as the example,
+and say 
+```console
+$ python -i timing_diagram.py 
+```
+