diff --git a/icebox/icebox_vlog.py b/icebox/icebox_vlog.py
index a956e8f..22f3f27 100755
--- a/icebox/icebox_vlog.py
+++ b/icebox/icebox_vlog.py
@@ -50,7 +50,7 @@ Usage: icebox_vlog [options] [bitmap.asc]
         name for the exported module (default: "chip")
 
     -p <pcf-file>
-        use the set_io command from the specified pcf file
+        use the set_io commands from the specified pcf file
 
     -P <pcf-file>
         like -p, enable some hacks for pcf files created