nRF5 SDK for Mesh v2.2.0
Light switch demo


This demo project consists of four sub examples - The light switch server with and without GATT proxy support, the light switch client and a provisioner example.

It demonstrates the mesh eco system containing devices acting in two roles, a Provisioner role, and a Node role. In addition, it demonstrates how to use custom models by using the Generic OnOff model in a real application.

Getting started

Hardware requirements

See compatiblity section for the supported boards.

Running the demo

Running the example

To build the examples, follow the instructions in Building the Mesh Stack. Refer to the How to run examples section in Examples README for the commands required to program a device using nrfjprog.

  1. Erase the device flash of your development board, and program the SoftDevice.
  2. Flash the provisioner and client firmware on individual boards and the server firmware on other boards.
  3. After a reset, press Button 1 on the provisioner to start the provisioning and configuration of the devices. The provisioner first provisions and configures the client and then moves on to provision and configure the servers, one by one.
  4. Use the RTT viewer to view the RTT output generated by the provisioner.

The provisioner prints details about the provisioning and the configuration process in the RTT log. When provisioner is scanning and provisioning a device, LED 1 on the Provisioner board is turned ON. When configuration procedure is underway, LED 2 on the provisioner board is turned ON.

The provisioner configures the client model instances on the client board. The client example is configured as follows:

Once provisioning and configuration of the client node and at least one of the server nodes is completed, you can press buttons on the client to see the LEDs getting toggled on the associated servers.

If an RTT terminal is available and connected to the client, sending the ASCII numbers 03 will have the same effect as pressing the buttons.

You can also press Button 1 on the servers to locally toggle the state of their LED 1, and the status reflecting this state will be sent to the client board. You can see the status printed in the RTT log of the client board.

If any of the devices are powered off and back on, they will remember their configuration in flash and rejoin the network. More information about the flash manager can be found in the flash manager documentation.

If provisioner encounters the error during the provisioning or configuration process for a certain node, you can reset the provisioner to restart this process for that node.

Provisioning with nRF Mesh app

  1. Switch off the provisioner board, and flash the client and server firmwares again.
  2. Download the nRF Mesh app for your mobile phone (iOS or Android) and provision these nodes.
  3. Bind the Generic OnOff client and server model instances on the nodes with the same app key.
  4. Set the publish address of the 1st Generic OnOff client model instance on the client example to the unicast address of any server node.
  5. Press Button 1 on the client board to turn ON LED 1 on the corresponding server board.
  6. Press Button 2 on the client board to turn OFF LED 1 on the corresponding server board.


Mesh provisioner

The provisoner provisions and configures the nodes to setup a demo mesh network. It is implemented as a multi-layered state machine due to the asynchronous nature of the provisioning and configuration process.

The provisioner first provisions and configures a client device with a known UUID. After this it moves on to provision and configure the server devices.

The following diagram shows the typical state transitions of the provisioner while provisioning and configuring light switch servers.

Light switch client state diagram

For more information on how a provisioner works, see the Mesh provisioning Guide.

Light switch client

The Light switch client has a provisionee role in the network. The client has four buttons to control the state of LED 1 on servers. It instantiates two instances of Generic OnOff Client model. The provisioner configures this client model instances to communicate with servers.

Light switch server

The Light switch server has a provisionee role in the network. It instantiates one instance of the Generic OnOff server model to control the state of LED 1. The provisioner configures this server model instance to communicate with the client model on the client board and to publish a message when value of the OnOff state changes.

State diagram for the Light switch server

GATT Proxy

Variants of both the Light switch server and Light switch client examples with additional provisioning over GATT (PB-GATT) and Proxy Server support are provided as the Light switch proxy server and Light switch proxy client, respectively. The proxy-enabled examples behave in the same way as the non-proxy variant. Note that the Proxy Client role is not supported.

Read more about the Proxy feature in GATT provisioning and Proxy.

Light switch server (Proxy)

The Light switch proxy server example application has the same behavior as the light switch server, but additionally has the proxy role enabled. As proxy is only supported on the nRF52, cmake will not generate the proxy server example for nRF51.

The proxy server application can either be provisioned and configured by the provisioner device like the light switch server, or by a GATT-based provisioner. After provisioning, the proxy server application starts advertising a connectable proxy beacon, which can be connected to by a Proxy Client to interact with the mesh. The Proxy Client acts like any other mesh device, but sends all its mesh communication over a BLE connection to a Proxy Server, which relays it into the mesh.

Light switch client (Proxy)

The Light switch proxy client example has the same behavior as the light switch client, but with the added Proxy Server support. The name might suggest that it also supports the Proxy Client, however that is not the case.

Generic OnOff client/server model

The Generic OnOff Client/Server is used for manipulating an on/off state. Note that when the server has a publish address set (as in this example), the server will publish any operation of its state change to its publish address.

More information about the Generic OnOff model can be found in the Generic OnOff model documentation and Generic OnOff server behaviour documentation.


See the Exploring Mesh APIs using light switch example document to get a quick overview of the various SDK APIs.

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