diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..9239c9f
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "src/JT809.Protocol"]
+	path = src/JT809.Protocol
+	url = https://github.com/SmallChi/JT809.git
diff --git a/src/JT809.Protocol b/src/JT809.Protocol
new file mode 160000
index 0000000..b84dec6
--- /dev/null
+++ b/src/JT809.Protocol
@@ -0,0 +1 @@
+Subproject commit b84dec6af9a812ea0ea02850987fd4455d1f20ee