diff -r 670cd8aa273d -r 1a128e86d4f6 master/master.c
--- a/master/master.c	Fri Dec 09 10:46:25 2011 +0100
+++ b/master/master.c	Fri Dec 09 10:35:23 2011 +0100
@@ -549,6 +549,10 @@
     master->cb_data = master;
 
     master->phase = EC_IDLE;
+
+    // reset number of responding slaves to trigger scanning
+    master->fsm.slaves_responding = 0;
+
     ret = ec_master_thread_start(master, ec_master_idle_thread,
             "EtherCAT-IDLE");
     if (ret)