diff --git a/MAC/APL/PIC/RSPDriver/src/CDOWrite.cc b/MAC/APL/PIC/RSPDriver/src/CDOWrite.cc
index 49dbcff72fcc217671bbf2905177eb622aa985e5..b550867372fe56f9f65f755b551a5ab7c2aff0dc 100644
--- a/MAC/APL/PIC/RSPDriver/src/CDOWrite.cc
+++ b/MAC/APL/PIC/RSPDriver/src/CDOWrite.cc
@@ -136,6 +136,11 @@ uint16 CDOWrite::compute_ip_checksum(void* addr, int count)
 
 void CDOWrite::sendrequest()
 {
+  // write register (with same setting) every second if WRITE_CDO_ONCE == 0
+  if (0 == GET_CONFIG("RSPDriver.WRITE_CDO_ONCE", i)) {
+    Cache::getInstance().getState().cdo().write(getBoardId());
+  }
+
   // skip update if the CDO settings have not been modified
   if (RTC::RegisterState::WRITE != Cache::getInstance().getState().cdo().get(getBoardId()))
   {
@@ -153,9 +158,10 @@ void CDOWrite::sendrequest()
       cdo.hdr.set(MEPHeader::CDO_SETTINGS_HDR);
 
       cdo.station_id       = getBoardId() + 1;
-      cdo.configuration_id = 0;
-      cdo.format           = 0;
-      cdo.antenna_id       = 0;
+      // fill in some magic so we recognise these fields easily in tcpdump/ethereal output
+      cdo.configuration_id = 0xBBAA;
+      cdo.format           = 0xDDCC;
+      cdo.antenna_id       = 0xFFEE;
       memcpy(cdo.destination_mac, m_dstmac, ETH_ALEN);
 
       m_hdr = cdo.hdr;
diff --git a/MAC/APL/PIC/RSPDriver/src/RSPDriver.conf.in b/MAC/APL/PIC/RSPDriver/src/RSPDriver.conf.in
index d21a1c4980fdc593bb1ff590b935503d012bffa7..0e0ea72bec277032e6e1258f62b3dcd0351dccfa 100644
--- a/MAC/APL/PIC/RSPDriver/src/RSPDriver.conf.in
+++ b/MAC/APL/PIC/RSPDriver/src/RSPDriver.conf.in
@@ -71,8 +71,8 @@ RSPDriver.MAC_ADDR_23=00:00:00:00:00:17
 # Data output payload size.
 # Should eventually be computed dynamically
 # based on settings.
-#
-RSPDriver.OUTPUT_PAYLOAD_SIZE=736
+# now 1744 was 736
+RSPDriver.OUTPUT_PAYLOAD_SIZE=1744
 
 #
 # Destination IP and MAC address for data packets
@@ -198,7 +198,10 @@ RSPDriver.LOOPBACK_MODE=0
 #
 RSPDriver.WRITE_RSU=1
 RSPDriver.WRITE_BS=1
-RSPDriver.WRITE_CDO=0
+RSPDriver.WRITE_CDO=1
+# WRITE_CDO_ONCE, if set to 1 only write CDO register once at startup
+# otherwise rewrite same data every update (= second)
+RSPDriver.WRITE_CDO_ONCE=0
 RSPDriver.READ_STATUS=1
 RSPDriver.WRITE_BF=1
 RSPDriver.WRITE_SS=1