Added new configurable block for demapping of control channels.
diff --git a/examples/receiver_usrp.grc b/examples/receiver_usrp.grc
index 7202f10..82f0109 100644
--- a/examples/receiver_usrp.grc
+++ b/examples/receiver_usrp.grc
@@ -1,4 +1,5 @@
 <?xml version='1.0' encoding='ASCII'?>
+<?grc format='1' created='3.7.6'?>
 <flow_graph>
   <timestamp>Thu Nov  6 14:43:18 2014</timestamp>
   <block>
@@ -68,6 +69,195 @@
     <key>variable</key>
     <param>
       <key>id</key>
+      <value>CHANNEL_UNKNOWN</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(600, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>CCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>2</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(800, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>AGCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>4</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(928, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>BCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(736, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>PCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(992, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>SDCCH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>6</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(1056, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>RACH</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>3</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(864, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
       <value>samp_rate</value>
     </param>
     <param>
@@ -269,45 +459,6 @@
     </param>
   </block>
   <block>
-    <key>gsm_get_bcch_or_ccch_bursts</key>
-    <param>
-      <key>id</key>
-      <value>gsm_get_bcch_or_ccch_bursts_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>d_fn51_start</key>
-      <value>2</value>
-    </param>
-    <param>
-      <key>alias</key>
-      <value></value>
-    </param>
-    <param>
-      <key>affinity</key>
-      <value></value>
-    </param>
-    <param>
-      <key>minoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(674, 268)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
-  <block>
     <key>gsm_message_printer</key>
     <param>
       <key>id</key>
@@ -335,41 +486,6 @@
     </param>
   </block>
   <block>
-    <key>gsm_control_channels_decoder</key>
-    <param>
-      <key>id</key>
-      <value>gsm_control_channels_decoder_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>alias</key>
-      <value></value>
-    </param>
-    <param>
-      <key>affinity</key>
-      <value></value>
-    </param>
-    <param>
-      <key>minoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(916, 272)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
-  <block>
     <key>blocks_socket_pdu</key>
     <param>
       <key>id</key>
@@ -447,6 +563,10 @@
       <value>1024</value>
     </param>
     <param>
+      <key>freqhalf</key>
+      <value>True</value>
+    </param>
+    <param>
       <key>wintype</key>
       <value>firdes.WIN_BLACKMAN_hARRIS</value>
     </param>
@@ -495,6 +615,22 @@
       <value>True</value>
     </param>
     <param>
+      <key>tr_mode</key>
+      <value>qtgui.TRIG_MODE_FREE</value>
+    </param>
+    <param>
+      <key>tr_level</key>
+      <value>0.0</value>
+    </param>
+    <param>
+      <key>tr_chan</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>tr_tag</key>
+      <value>""</value>
+    </param>
+    <param>
       <key>label1</key>
       <value></value>
     </param>
@@ -1367,57 +1503,6 @@
     </param>
   </block>
   <block>
-    <key>gsm_receiver</key>
-    <param>
-      <key>id</key>
-      <value>gsm_receiver_0</value>
-    </param>
-    <param>
-      <key>_enabled</key>
-      <value>True</value>
-    </param>
-    <param>
-      <key>osr</key>
-      <value>4</value>
-    </param>
-    <param>
-      <key>cell_allocation</key>
-      <value>[0]</value>
-    </param>
-    <param>
-      <key>tseq_nums</key>
-      <value>[]</value>
-    </param>
-    <param>
-      <key>num_streams</key>
-      <value>1</value>
-    </param>
-    <param>
-      <key>alias</key>
-      <value></value>
-    </param>
-    <param>
-      <key>affinity</key>
-      <value></value>
-    </param>
-    <param>
-      <key>minoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>maxoutbuf</key>
-      <value>0</value>
-    </param>
-    <param>
-      <key>_coordinate</key>
-      <value>(434, 272)</value>
-    </param>
-    <param>
-      <key>_rotation</key>
-      <value>0</value>
-    </param>
-  </block>
-  <block>
     <key>gsm_input</key>
     <param>
       <key>id</key>
@@ -1468,6 +1553,135 @@
       <value>0</value>
     </param>
   </block>
+  <block>
+    <key>gsm_control_channels_decoder</key>
+    <param>
+      <key>id</key>
+      <value>gsm_control_channels_decoder_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(916, 272)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gsm_universal_ctrl_chans_demapper</key>
+    <param>
+      <key>id</key>
+      <value>gsm_universal_ctrl_chans_demapper_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>starts_fn_mod51</key>
+      <value>[2,6,12,16,22,26,32,36,42,46]</value>
+    </param>
+    <param>
+      <key>channel_types</key>
+      <value>[BCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH,CCCH]</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(648, 272)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gsm_receiver</key>
+    <param>
+      <key>id</key>
+      <value>gsm_receiver_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>osr</key>
+      <value>4</value>
+    </param>
+    <param>
+      <key>cell_allocation</key>
+      <value>[0]</value>
+    </param>
+    <param>
+      <key>tseq_nums</key>
+      <value>[]</value>
+    </param>
+    <param>
+      <key>num_streams</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>alias</key>
+      <value></value>
+    </param>
+    <param>
+      <key>affinity</key>
+      <value></value>
+    </param>
+    <param>
+      <key>minoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>maxoutbuf</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(434, 272)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
   <connection>
     <source_block_id>uhd_usrp_source_0</source_block_id>
     <sink_block_id>qtgui_freq_sink_x_0</sink_block_id>
@@ -1475,12 +1689,6 @@
     <sink_key>0</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_get_bcch_or_ccch_bursts_0</source_block_id>
-    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
-    <source_key>bursts</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
     <source_block_id>gsm_control_channels_decoder_0</source_block_id>
     <sink_block_id>gsm_message_printer_0</sink_block_id>
     <source_key>msgs</source_key>
@@ -1493,12 +1701,6 @@
     <sink_key>pdus</sink_key>
   </connection>
   <connection>
-    <source_block_id>gsm_receiver_0</source_block_id>
-    <sink_block_id>gsm_get_bcch_or_ccch_bursts_0</sink_block_id>
-    <source_key>C0</source_key>
-    <sink_key>bursts</sink_key>
-  </connection>
-  <connection>
     <source_block_id>uhd_usrp_source_0</source_block_id>
     <sink_block_id>gsm_input_0</sink_block_id>
     <source_key>0</source_key>
@@ -1510,4 +1712,16 @@
     <source_key>0</source_key>
     <sink_key>0</sink_key>
   </connection>
+  <connection>
+    <source_block_id>gsm_universal_ctrl_chans_demapper_0</source_block_id>
+    <sink_block_id>gsm_control_channels_decoder_0</sink_block_id>
+    <source_key>bursts</source_key>
+    <sink_key>bursts</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>gsm_receiver_0</source_block_id>
+    <sink_block_id>gsm_universal_ctrl_chans_demapper_0</sink_block_id>
+    <source_key>C0</source_key>
+    <sink_key>bursts</sink_key>
+  </connection>
 </flow_graph>