add default nettype none
diff --git a/verilog/gl/digital_pll.v b/verilog/gl/digital_pll.v
index 0b1f5ed..4310af0 100644
--- a/verilog/gl/digital_pll.v
+++ b/verilog/gl/digital_pll.v
@@ -1,3 +1,4 @@
+`default_nettype none
 /* Generated by Yosys 0.9+3621 (git sha1 84e9fa7, gcc 8.3.1 -fPIC -Os) */
 
 module digital_pll(dco, enable, osc, resetb, VPWR, VGND, clockp, div, ext_trim);