diff --git a/sys/arch/atari/dev/grfabs.c b/sys/arch/atari/dev/grfabs.c
index 70394c7d981e..d79077cdbe56 100644
--- a/sys/arch/atari/dev/grfabs.c
+++ b/sys/arch/atari/dev/grfabs.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: grfabs.c,v 1.8 1996/03/08 21:52:50 leo Exp $	*/
+/*	$NetBSD: grfabs.c,v 1.9 1996/09/16 06:49:03 leo Exp $	*/
 
 /*
  * Copyright (c) 1995 Leo Weppelman.
@@ -96,24 +96,17 @@ u_long gra_def_color16[16] = {
  * Initialize list of posible video modes.
  */
 int
-grfabs_probe()
+grfabs_probe(probe_fun)
+grf_probe_t	probe_fun;
 {
 	static int	inited = 0;
 
-	if (inited)
-		return (1);	/* Has to be done only once */
-	inited++;
+	if (!inited) {
+		LIST_INIT(&modes);
+		inited = 1;
+	}
+	(*probe_fun)(&modes);
 
-	LIST_INIT(&modes);
-
-#ifdef FALCON_VIDEO
-	if (machineid & ATARI_FALCON)
-		falcon_probe_video(&modes);
-#endif /* FALCON_VIDEO */
-#ifdef TT_VIDEO
-	if (machineid & ATARI_TT)
-		tt_probe_video(&modes);
-#endif /* TT_VIDEO */
 	return ((modes.lh_first == NULL) ? 0 : 1);
 }
 
diff --git a/sys/arch/atari/dev/grfabs_tt.h b/sys/arch/atari/dev/grfabs_tt.h
new file mode 100644
index 000000000000..5e9f4564a8b4
--- /dev/null
+++ b/sys/arch/atari/dev/grfabs_tt.h
@@ -0,0 +1,48 @@
+/*	$NetBSD: grfabs_tt.h,v 1.1 1996/09/16 06:50:34 leo Exp $	*/
+
+/*
+ * Copyright (c) 1996 Leo Weppelman.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by Leo Weppelman
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _GRFABS_TT_H
+#define _GRFABS_TT_H
+
+/*
+ * Colormap related macro's
+ */
+#define CM_L2TT(v) \
+    (((0x000f0000 & (v)) >> 8) | ((0x00000f00 & (v)) >> 4) |\
+      (0x0000000f & (v)))
+#define CM_TT2L(v) \
+    ((((0x00000f00 & (v)) * 0xff / 0xf) << 8) |\
+     (((0x000000f0 & (v)) * 0xff / 0xf) << 4) |\
+       (0x0000000f & (v)) * 0xff / 0xf)
+
+void tt_probe_video __P((MODES *));
+#endif /*  _GRFABS_TT_H */