diff --git a/printf.asm b/printf.asm
index fc7cc03..1dad2e4 100644
--- a/printf.asm
+++ b/printf.asm
@@ -26,7 +26,7 @@
 ;  L		long
 ;  C		single character
 ;  O		octal
-;  S		string
+;  S		address of string
 
  IFUSED	printf#.str