 EthernetServer server = EthernetServer(TCP_PORT);
 EthernetClient client;
 boolean clientConnected = false;
+unsigned long commTime;
 const byte modbusHeader[MODBUS_HDR_LEN] = { 
   0x00, 0x00, // Transaction identifier
   0x00, 0x00, // Protocol identifier

      DEBUG_PRINTLN("Response not required");
    }
  }

  DEBUG_WRITETIME();
  DEBUG_PRINTLN();
}

  }

  if (!clientConnected) {
    // reinit Ethernet if client can't connect
    if (inactiveSpan > REINIT_TIME) {
      initEthernet();
    }
    
    // connection is considered to be established only when data are received
    client = server.available();
    if (client) {
