--- a/master/frame.c	Tue Feb 28 13:07:05 2006 +0000
+++ b/master/frame.c	Thu Mar 02 11:19:27 2006 +0000
@@ -253,6 +253,9 @@
     unsigned int command_size, frame_size, i;
     uint8_t *data;
 
+    if (unlikely(!frame->master->device.link_state))
+        return -1;
+
     if (unlikely(frame->master->debug_level > 0)) {
         EC_DBG("ec_frame_send\n");
     }