ready for submission
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..db39e02
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "verilog/rtl/vga-clock"]
+	path = verilog/rtl/vga-clock
+	url = https://github.com/mattvenn/vga-clock