diff --git a/.gitignore b/.gitignore
index 23884e3..696a56e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,6 +22,8 @@
 *.tab
 *.txt
 !/examples/*/*.txt
+/examples/Makefile*
+/examples/*/Makefile*
 **/spiNNakerGraphFrontEnd.cfg
 **/spynnaker.cfg
 **/application_generated_data_files
diff --git a/c_code/comms_i.c b/c_code/comms_i.c
index f89876c..d5253ea 100644
--- a/c_code/comms_i.c
+++ b/c_code/comms_i.c
@@ -274,7 +274,12 @@ void i_net_stop_packet (uint key)
 // ------------------------------------------------------------------------
 void i_dlrv_packet (void)
 {
-  // restart tick
+#ifdef DEBUG
+  io_printf (IO_BUF, "timeout (h:%u e:%u p:%u t:%u) - restarted\n",
+	     epoch, example_cnt, phase, tick
+    );
+#endif
+
   if (phase == SPINN_FORWARD)
   {
     // initialise thread semaphore
diff --git a/c_code/comms_s.c b/c_code/comms_s.c
index fa4e0cb..327b6fe 100644
--- a/c_code/comms_s.c
+++ b/c_code/comms_s.c
@@ -468,12 +468,26 @@ void s_fsgn_packet (void)
 // ------------------------------------------------------------------------
 void s_dlrv_packet (void)
 {
+#ifdef DEBUG
+  io_printf (IO_BUF, "timeout (h:%u e:%u p:%u t:%u) - restarted!\n",
+	     epoch, example_cnt, phase, tick
+    );
+  io_printf (IO_BUF, "(bd:%u)\n", sb_done);
+  for (uint i = 0; i < scfg.num_units; i++)
+  {
+    io_printf (IO_BUF, "%2d: (fa:%u ba:%u)\n", i,
+	       sf_arrived[i], sb_arrived[i]
+      );
+  }
+  io_printf (IO_BUF, "(fptd:0x%02x bptd:0x%02x)\n", sf_thrds_pend, sb_thrds_pend);
+#endif
+
   // restart tick
   if (phase == SPINN_FORWARD)
   {
 #ifdef DEBUG
-        fsg_sent = 0;
-        fsg_recv = 0;
+    fsg_sent = 0;
+    fsg_recv = 0;
 #endif
 
     // initialise thread semaphore,
@@ -490,6 +504,11 @@ void s_dlrv_packet (void)
   }
   else
   {
+#ifdef DEBUG
+    bsg_sent = 0;
+    bsg_recv = 0;
+#endif
+
     // initialise thread semaphore,
     sb_thrds_pend = sb_thrds_init;
 
diff --git a/c_code/comms_t.c b/c_code/comms_t.c
index 0cd195b..80afc78 100644
--- a/c_code/comms_t.c
+++ b/c_code/comms_t.c
@@ -420,13 +420,26 @@ void t_net_stop_packet (uint key)
 // ------------------------------------------------------------------------
 void t_dlrv_packet (void)
 {
+#ifdef DEBUG
+  io_printf (IO_BUF, "timeout (h:%u e:%u p:%u t:%u) - restarted\n",
+	     epoch, example_cnt, phase, tick
+    );
+  io_printf (IO_BUF, "(tactive:%u ta:%u/%u tb:%u/%u)\n",
+	     tf_active, tf_arrived, tcfg.num_units,
+	     tb_arrived, tcfg.num_units
+    );
+  io_printf (IO_BUF, "(fptd:0x%02x bptd:0x%02x)\n",
+	     tf_thrds_pend, tb_thrds_pend
+    );
+#endif
+
   // restart tick
   if (phase == SPINN_FORWARD)
   {
 #ifdef DEBUG
-        crt_sent = 0;
-        crt_recv = 0;
-        fsg_recv = 0;
+    crt_sent = 0;
+    crt_recv = 0;
+    fsg_recv = 0;
 #endif
 
     // initialise thread semaphore,
@@ -444,6 +457,11 @@ void t_dlrv_packet (void)
   }
   else
   {
+#ifdef DEBUG
+    bsg_sent = 0;
+    bsg_recv = 0;
+#endif
+
     // initialise thread semaphore,
     tb_thrds_pend = tb_thrds_init;
 
diff --git a/c_code/comms_w.c b/c_code/comms_w.c
index b619bd5..bc26f38 100644
--- a/c_code/comms_w.c
+++ b/c_code/comms_w.c
@@ -359,11 +359,22 @@ void w_net_stop_packet (uint key)
 // ------------------------------------------------------------------------
 void w_dlrv_packet (void)
 {
+#ifdef DEBUG
+  io_printf (IO_BUF, "timeout (h:%u e:%u p:%u t:%u) - restarted\n",
+	     epoch, example_cnt, phase, tick
+    );
+  io_printf (IO_BUF, "(fp:%u  fc:%u)\n", wf_procs, wf_comms);
+  io_printf (IO_BUF, "(fa:%u/%u ba:%u/%u)\n",
+	     wf_arrived, wcfg.num_rows, wb_arrived, wcfg.num_cols
+    );
+  io_printf (IO_BUF, "(fptd:0x%02x bptd:0x%02x)\n", wf_thrds_pend, wb_thrds_pend);
+#endif
+
   // restart tick
   if (phase == SPINN_FORWARD)
   {
 #ifdef DEBUG
-        fsg_sent = 0;
+    fsg_sent = 0;
 #endif
 
     // initialise thread semaphore,
diff --git a/c_code/process_s.c b/c_code/process_s.c
index 8d2c883..e659325 100644
--- a/c_code/process_s.c
+++ b/c_code/process_s.c
@@ -276,6 +276,8 @@ void sb_advance_tick (uint unused0, uint unused1)
 
 #ifdef DEBUG
   tot_tick++;
+  bsg_sent = 0;
+  bsg_recv = 0;
 #endif
 
   // check if end of BACKPROP phase
diff --git a/c_code/process_t.c b/c_code/process_t.c
index 5ecb4bd..e1fba31 100644
--- a/c_code/process_t.c
+++ b/c_code/process_t.c
@@ -287,6 +287,8 @@ void tb_advance_tick (uint unused0, uint unused1)
 
 #ifdef DEBUG
   tot_tick++;
+  bsg_sent = 0;
+  bsg_recv = 0;
 #endif
 
   // update pointer to processing unit outputs,
diff --git a/c_code/threshold.c b/c_code/threshold.c
index 2c2abc3..5daaa05 100644
--- a/c_code/threshold.c
+++ b/c_code/threshold.c
@@ -293,6 +293,19 @@ void timeout (uint ticks, uint unused)
       // send deadlock recovery packet to all other cores
       while (!spin1_send_mc_packet(tf_dlrv_key, 0, NO_PAYLOAD));
 
+#ifdef DEBUG
+      io_printf (IO_BUF, "timeout (h:%u e:%u p:%u t:%u) - restarted\n",
+		 epoch, example_cnt, phase, tick
+	);
+      io_printf (IO_BUF, "(tactive:%u ta:%u/%u tb:%u/%u)\n",
+		 tf_active, tf_arrived, tcfg.num_units,
+		 tb_arrived, tcfg.num_units
+	);
+      io_printf (IO_BUF, "(fptd:0x%02x bptd:0x%02x)\n",
+		 tf_thrds_pend, tb_thrds_pend
+	);
+#endif
+
       // restart tick
       if (phase == SPINN_FORWARD)
       {
@@ -317,6 +330,11 @@ void timeout (uint ticks, uint unused)
       }
       else
       {
+#ifdef DEBUG
+	bsg_sent = 0;
+	bsg_recv = 0;
+#endif
+
         // initialise thread semaphore,
         tb_thrds_pend = tb_thrds_init;