7 Replies Latest reply on Feb 23, 2020 10:54 PM by DheerajP_41

    questions about LPN device

    mawu_4270096

      Hi  all:

       

           now I  am not very clear about that  how  the LPN device  is  to be added  into  the Bluetooth mesh  networking. as we know, the LPN device must need a friend node

          to communication with other devices. now the LPN how to choose the networking friend node device. if the provisioning procedure of  the LPN device requires  the participation of the friend node.

       

        now I download the mesh provision client firmware into  the CYW20735Q60EVB-01 board and use the mesh client control to create a Bluetooth mesh networking.

        I  add a dimmable light device into the networking.  the dimmable light  can be controlled by mesh client control.  finally I configure the mesh light ctl server to LPN node

        the configuration as below:


          .features           = WICED_BT_MESH_CORE_FEATURE_BIT_LOW_POWER, // A bit field indicating the device features. In Low Power mode no Relay, no Proxy and no       Friend
          .friend_cfg         =                                           // Empty Configuration of the Friend Feature
          {
              .receive_window = 0,                                        // Receive Window value in milliseconds supported by the Friend node.
              .cache_buf_len  = 0,                                        // Length of the buffer for the cache
              .max_lpn_num    = 0                                         // Max number of Low Power Nodes with established friendship. Must be > 0 if Friend feature is supported.
          },
          .low_power          =                                           // Configuration of the Low Power Feature
          {
              .rssi_factor           = 2,                                 // contribution of the RSSI measured by the Friend node used in Friend Offer Delay calculations.
              .receive_window_factor = 2,                                 // contribution of the supported Receive Window used in Friend Offer Delay calculations.
              .min_cache_size_log    = 7,                                 // minimum number of messages that the Friend node can store in its Friend Cache.
              .receive_delay         = 100,                               // Receive delay in 1 ms units to be requested by the Low Power node.
              .poll_timeout          = 10,                                // Poll timeout in 100ms units to be requested by the Low Power node.
              .startup_unprovisioned_adv_to = 128                         // Interval in seconds of the advertisments of unprovisioned beacon and service on startup. Value 0 means default 30 seconds.
          },

       

      when I want to add the device into the networking. the mesh client control output print messages is below:

       

          it seems the provisioning procedure is failure, now I don't know  how to solve this problem !

       

       

      thanks!

       

       

      Mandy

        • 1. Re: questions about LPN device
          DheerajP_41

          Hi,

           

          If a node is unreachable, it means a provisioned node is not in active state in the network while performing security update for example: key refresh.

           

          When Node Unreachable can occur:

          If you have provisioned a node at some point and, did not remove in a secure way (instead of issuing  node reset from MeshClient, if you do hardware factory reset on the board) then the MeshClient database will still be having the node data and meshclient will try to do key refresh for that device also.

           

          You can create a new network and try your experiment.

           

          Thanks,

          -Dheeraj

          1 of 1 people found this helpful
          • 2. Re: questions about LPN device
            mawu_4270096

            Hi  DheerajP_41:

                 if I have configured  the device to LPN,  it seems that the provisioning is always failure!

                 I want to know if there is any LPN examples I want to use

             

             

            thanks!

             

            mandy

             

                

             

            • 3. Re: questions about LPN device
              mawu_4270096

              Hi DheerajP_41:

                the uart  print messages is below:

                  

               

               

              I  want to know if the current version  sdk (WICED-SDK Version: Wiced_006.004.000.0061) don't support  the node low power feature?

               

               

              thanks!

               

              mandy

              • 4. Re: questions about LPN device
                DheerajP_41

                Hi,

                 

                For a quick test I have taken the on_off_switch application in wiced_6.4 and programmed with LOW_POWER_NODE=1 on 20735.

                It worked for me.

                 

                After programming the LPN will search for a friend node and make a friendship link with it. After that the LPN will go to sleep and friend node will cache data for the LPN. The above log which you mentioned comes after the successful provision. You need a friend feature enable device near the LPN to get it work.

                 

                Thanks,

                -Dheeraj

                1 of 1 people found this helpful
                • 5. Re: questions about LPN device
                  mawu_4270096

                  Hi .

                  I want to know how does the LPN node choose a node to make it's  friendship node

                   

                   

                  thanks!

                   

                  Mandy

                  • 6. Re: questions about LPN device
                    mawu_4270096

                    Hi

                        I use the on_off_switch application programmed with LOW_POWER_NODE=1 on 20735 to do a experiment. the on_off_switch    can be  provisioned successfully.  but I don't know how to control the on off switch device  by the mesh client control.

                    there is a device which has the friend, relay capacity in the network!

                     

                     

                    thanks!

                     

                    mandy

                    • 7. Re: questions about LPN device
                      DheerajP_41

                      Hi,

                       

                      on_off_switch is a client application. We can use it to change the server device state (On/OFF).

                       

                      After provisioning process,  the LPN will scan for a friendnode and establishes a friendship link with it.  Whenever the user send a valid message to an LPN device the friend node will cache it (if the LPN is on sleep) and transfer it to the LPN later(when LPN polls the friend node).

                       

                      Here, for testing you can provision a LPN (on_off_switch) node and a friend node (Eg. dimmable_light) into a single network. So that LPN will establish friendship with the friend node. After that LPN will go to sleep after certain timeout periodically. Whenever you presses the user button the LPN wakes up and send the mesh message to the dimmable_light to turn it on or off.

                       

                      Thanks,

                      -Dheeraj

                      1 of 1 people found this helpful