diff --git a/.gitmodules b/.gitmodules
index feda7e50f1f7a438af7ba67dd5c268402ee3d781..6894ea53228ebc1364262993f8a6ee7ab16b32ba 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,4 @@
 [submodule "tools/chipkit_flow"]
 	path = tools/chipkit_flow
 	url = https://git.soton.ac.uk/soclabs/chipkit_flow.git
+	branch = main