diff --git a/libsrc/c16/slow.s b/libsrc/c16/slow.s
index 18b8c231c..70e461a9a 100644
--- a/libsrc/c16/slow.s
+++ b/libsrc/c16/slow.s
@@ -1,22 +1 @@
-;
-; Marco van den Heuvel, 2018-03-28
-;
-; void slow (void);
-; /* Switch the CPU into single clock mode. */
-;
-
-        .export         _slow
-
-        .include        "plus4.inc"
-
-
-.proc   _slow
-
-        lda     TED_CLK
-        ora     #%00000010
-        sta     TED_CLK
-        rts
-
-.endproc
-
-
+.include "../plus4/slow.s"