CHIP ESP32 Temperature Sensor Example

This example is meant to represent a minimal-sized application.

CHIP ESP32 Temperature Sensor Example

Building the Example Application

Building the example application requires the use of the Espressif ESP32 IoT Development Framework and the xtensa-esp32-elf toolchain.

The VSCode devcontainer has these components pre-installed, so you can skip this step. To install these components manually, follow these steps:

Clone the Espressif ESP-IDF and checkout v4.3 tag

  $ mkdir ${HOME}/tools
  $ cd ${HOME}/tools
  $ git clone https://github.com/espressif/esp-idf.git
  $ cd esp-idf
  $ git checkout v4.3
  $ git submodule update --init
  $ ./install.sh

Install ninja-build
```
  $ sudo apt-get install ninja-build
```

Currently building in VSCode and deploying from native is not supported, so make sure the IDF_PATH has been exported(See the manual setup steps above).

Setting up the environment

$ cd ${HOME}/tools/esp-idf
$ ./install.sh
$ . ./export.sh
$ cd {path-to-connectedhomeip}

To download and install packages.

$ source ./scripts/bootstrap.sh
$ source ./scripts/activate.sh

If packages are already installed then simply activate them.

$ source ./scripts/activate.sh

Configuration Options
This application uses ESP32-DevKitC as a default device type. To use other ESP32 based device types, please refer examples/all-clusters-app/esp32
To build the demo application.
```
  $ idf.py build
```
After building the application, to flash it outside of VSCode, connect your device via USB. Then run the following command to flash the demo application onto the device and then monitor its output. If necessary, replace /dev/tty.SLAB_USBtoUART(MacOS) with the correct USB device name for your system(like /dev/ttyUSB0 on Linux). Note that sometimes you might have to press and hold the boot button on the device while it's trying to connect before flashing. For ESP32-DevKitC devices this is labeled in the functional description diagram.
```
  $ idf.py -p /dev/tty.SLAB_USBtoUART flash monitor
```
Note: Some users might have to install the VCP driver before the device shows up on /dev/tty.
Quit the monitor by hitting Ctrl+].
Note: You can see a menu of various monitor commands by hitting Ctrl+t Ctrl+h while the monitor is running.

If desired, the monitor can be run again like so:

  $ idf.py -p /dev/tty.SLAB_USBtoUART monitor

Commissioning and cluster control

Commissioning can be carried out using WiFi, BLE or Bypass.

Set the Rendezvous Mode for commissioning using menuconfig; the default Rendezvous mode is BLE.
```
 $ idf.py menuconfig
```

Select the Rendezvous Mode via Demo -> Rendezvous Mode. If Rendezvous Mode is Bypass then set the credentials of the WiFi Network (i.e. SSID and Password from menuconfig).

idf.py menuconfig -> Component config -> CHIP Device Layer -> WiFi Station Options

Now flash the device with the same command as before. (Use the right /dev device)
```
  $ idf.py -p /dev/tty.SLAB_USBtoUART flash monitor
```

The device should boot up. When device connects to your network, you will see a log like this on the device console.

  I (5524) chip[DL]: SYSTEM_EVENT_STA_GOT_IP
  I (5524) chip[DL]: IPv4 address changed on WiFi station interface: <IP_ADDRESS>...

Use python based device controller or standalone chip-tool or iOS chip-tool app or Android chip-tool app to communicate with the device.

Note: The ESP32 does not support 5GHz networks. Also, the Device will persist your network configuration. To erase it, simply run.

$ idf.py -p /dev/tty.SLAB_USBtoUART erase_flash

Setting up Python Controller

Once ESP32 is up and running, we need to set up a device controller to perform commissioning and cluster control.

Set up python controller.

   $ cd {path-to-connectedhomeip}
   $ ./scripts/build_python.sh -m platform

Execute the controller.

   $ source ./out/python_env/bin/activate
   $ chip-device-ctrl

Commissioning over BLE

Establish the secure session over BLE. BLE is the default mode in the application and is configurable through menuconfig.

 - chip-device-ctrl > ble-scan
 - chip-device-ctrl > connect -ble 3840 20202021 135246

 Parameters:
 1. Discriminator: 3840 (configurable through menuconfig)
 2. Setup-pin-code: 20202021 (configurable through menuconfig)
 3. Node ID: Optional.
    If not passed in this command, then it is auto-generated by the controller and displayed in the output of connect.
    The same value should be used in the next commands.
    We have chosen a random node ID which is 135246.

Add credentials of the Wi-Fi network you want the ESP32 to connect to, using the AddWiFiNetwork command and then enable the ESP32 to connect to it using EnableWiFiNetwork command. In this example, we have used TESTSSID and TESTPASSWD as the SSID and passphrase respectively.

 - chip-device-ctrl > zcl NetworkCommissioning AddWiFiNetwork 135246 0 0 ssid=str:TESTSSID credentials=str:TESTPASSWD breadcrumb=0 timeoutMs=1000

 - chip-device-ctrl > zcl NetworkCommissioning EnableNetwork 135246 0 0 networkID=str:TESTSSID breadcrumb=0 timeoutMs=1000

Close the BLE connection to ESP32, as it is not required hereafter.
```
 - chip-device-ctrl > close-ble
```
Resolve DNS-SD name and update address of the node in the device controller.
```
 - chip-device-ctrl > resolve 0 135246
```

Cluster control

The demo application supports TemperatureMeasurement and Basic cluster.
chip-device-ctrl > zcl Basic MfgSpecificPing 135246 1 0

Flashing app using script

Follow these steps to use ${app_name}.flash.py.
- First set IDF target, run set-target with one of the commands.
```
$ idf.py set-target esp32
$ idf.py set-target esp32c3
```
- Execute below sequence of commands

        $ export ESPPORT=/dev/tty.SLAB_USBtoUART
        $ export ESPBAUD=${baud_value}
        $ idf.py build
        $ idf.py flashing_script
        $ python ${app_name}.flash.py

Optimization

Optimization related to WiFi, BLuetooth, Asserts etc are the part of this example by default. To enable this option set is_debug=false from command-line.

idf.py -p /dev/tty.SLAB_USBtoUART -Dis_debug=false build flash monitor