diff --git a/main.S b/main.S
index 38896c5..15e2fd5 100644
--- a/main.S
+++ b/main.S
@@ -43,7 +43,7 @@ int_horizontal_sync:    ; +3
     push r31            ; +8
     push r30            ; +10
 
-    ; if (line >= VERTICAL_OFFSET), then enter
+    ; if (0 <= line < 256), then enter
     lds r30, line       ; +12
     lds r31, line + 1   ; +14
     adiw z, 1           ; +16