diff --git a/top.ys b/top.ys
index 9806b61..7abbdb1 100644
--- a/top.ys
+++ b/top.ys
@@ -3,4 +3,4 @@ proc
 opt
 alumacc
 share -aggressive
-synth_ice40 -top top -blif top.blif
+synth_ice40 -abc2 -top top -blif top.blif