diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..c4a0df1
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "libopencm3"]
+	path = libopencm3
+	url = https://github.com/libopencm3/libopencm3.git
diff --git a/libopencm3 b/libopencm3
new file mode 160000
index 0000000..503ceba
--- /dev/null
+++ b/libopencm3
@@ -0,0 +1 @@
+Subproject commit 503cebab87df3b49efbf46a9485f7bafaaeb1b33