diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -1,3 +1,4 @@
+### Usage
 1. `git submodule update --init --recursive`
 2. `mkdir build && cd build`
 3. `cmake ..`
diff --git a/SPEC/HM-BT4502+Bluetooth+Low+Energy+(BLE)+Pass-through+Module+Specification.pdf b/SPEC/HM-BT4502+Bluetooth+Low+Energy+(BLE)+Pass-through+Module+Specification.pdf
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