diff --git a/cpu/6502/6502def.h b/cpu/6502/6502def.h
index 7e17e4f4b..7117f621c 100644
--- a/cpu/6502/6502def.h
+++ b/cpu/6502/6502def.h
@@ -30,7 +30,7 @@
  *
  * Author: Oliver Schmidt <ol.sc@web.de>
  *
- * @(#)$Id: 6502def.h,v 1.13 2008/05/14 19:19:29 adamdunkels Exp $
+ * @(#)$Id: 6502def.h,v 1.14 2008/06/16 11:20:22 oliverschmidt Exp $
  */
 
 #ifndef __6502DEF_H__
@@ -128,7 +128,7 @@ typedef unsigned short uip_stats_t;
 #define cfs_write pfs_write
 #else /* WITH_PFS */
 #define CFS_READ  (O_RDONLY)
-#define CFS_WRITE (O_CREAT | O_TRUNC | O_RDWR)
+#define CFS_WRITE (O_CREAT | O_TRUNC | O_WRONLY)
 #define cfs_open  open
 #define cfs_close close
 #define cfs_read  read