esp32-core/libraries/Matter/examples/MatterTemperatureControlledCabinet

Matter Temperature Controlled Cabinet Example

This example demonstrates how to create a Matter-compatible temperature controlled cabinet device using an ESP32 SoC microcontroller with the temperature_number feature mode. This mode provides precise temperature setpoint control with min/max limits and optional step control.

Important: The temperature_number and temperature_level features are mutually exclusive. Only one can be enabled at a time. See MatterTemperatureControlledCabinetLevels example for temperature level control mode.

Supported Targets

SoC	Wi-Fi	Thread	BLE Commissioning	Status
ESP32	✅	❌	❌	Fully supported
ESP32-S2	✅	❌	❌	Fully supported
ESP32-S3	✅	❌	✅	Fully supported
ESP32-C3	✅	❌	✅	Fully supported
ESP32-C5	❌	✅	✅	Supported (Thread only)
ESP32-C6	✅	❌	✅	Fully supported
ESP32-H2	❌	✅	✅	Supported (Thread only)

Note on Commissioning:

• ESP32 & ESP32-S2 do not support commissioning over Bluetooth LE. For these chips, you must provide Wi-Fi credentials directly in the sketch code so they can connect to your network manually.
• ESP32-C6 Although it has Thread support, the ESP32 Arduino Matter Library has been precompiled using Wi-Fi only. In order to configure it for Thread-only operation it is necessary to build the project using Arduino as an IDF Component and to disable the Matter Wi-Fi station feature.
• ESP32-C5 Although it has Wi-Fi 2.4 GHz and 5 GHz support, the ESP32 Arduino Matter Library has been pre compiled using Thread only. In order to configure it for Wi-Fi operation it is necessary to build the project using Arduino as an ESP-IDF component and disable Thread network, keeping only Wi-Fi station.

Features

• Matter protocol implementation for a temperature controlled cabinet device
• Support for both Wi-Fi and Thread(*) connectivity
• Temperature setpoint control with min/max limits
• Temperature step control (always enabled, can be set via begin() or setStep())
• Temperature setpoint validation against min/max limits
• Button control for factory reset (decommission)
• Matter commissioning via QR code or manual pairing code
• Integration with Apple HomeKit, Amazon Alexa, and Google Home (*) It is necessary to compile the project using Arduino as IDF Component.

Use Case

Use this mode when you need precise temperature control with specific setpoint values (e.g., 4.0°C for a refrigerator, -18.0°C for a freezer). For preset-based temperature control using levels, see the MatterTemperatureControlledCabinetLevels example.

Hardware Requirements

• ESP32 compatible development board (see supported targets table)
• User button for factory reset (uses BOOT button by default)
• Optional: Connect temperature control hardware (relays, heaters, coolers, etc.) to implement actual temperature control

Pin Configuration

• Button: Uses BOOT_PIN by default

Software Setup

Prerequisites

1. Install the Arduino IDE (2.0 or newer recommended)
2. Install ESP32 Arduino Core with Matter support
3. ESP32 Arduino libraries:
   • Matter
   • Wi-Fi (only for ESP32 and ESP32-S2)

Configuration

Before uploading the sketch, configure the following:

1. Wi-Fi credentials (if not using BLE commissioning - mandatory for ESP32 | ESP32-S2):

   const char *ssid = "your-ssid";         // Change to your Wi-Fi SSID
   const char *password = "your-password"; // Change to your Wi-Fi password
   

2. Button pin configuration (optional): By default, the BOOT button (GPIO 0) is used for factory reset. You can change this to a different pin if needed.

   const uint8_t buttonPin = BOOT_PIN;  // Set your button pin here
   

3. Temperature range configuration (optional): Adjust the initial temperature setpoint, min, max, and step values in the begin() call:

   TemperatureCabinet.begin(4.0, -10.0, 10.0, 0.5);
   // Parameters: setpoint, min_temp, max_temp, step (all in Celsius)
   // Note: Step can also be set later using setStep() even if not provided here
   

Building and Flashing

1. Open the MatterTemperatureControlledCabinet.ino sketch in the Arduino IDE.
2. Select your ESP32 board from the Tools > Board menu.

3. Select "Huge APP (3MB No OTA/1MB SPIFFS)" from Tools > Partition Scheme menu.

4. Enable "Erase All Flash Before Sketch Upload" option from Tools menu.
5. Connect your ESP32 board to your computer via USB.
6. Click the Upload button to compile and flash the sketch.

Expected Output

Once the sketch is running, open the Serial Monitor at a baud rate of 115200. The Wi-Fi connection messages will be displayed only for ESP32 and ESP32-S2. Other targets will use Matter CHIPoBLE to automatically setup the IP Network. You should see output similar to the following, which provides the necessary information for commissioning:

Connecting to your-wifi-ssid
.......
Wi-Fi connected
IP address: 192.168.1.100

Matter Node is not commissioned yet.
Initiate the device discovery in your Matter environment.
Commission it to your Matter hub with the manual pairing code or QR code
Manual pairing code: 34970112332
QR code URL: https://project-chip.github.io/connectedhomeip/qrcode.html?data=MT%3A6FCJ142C00KA0648G00
Matter Node not commissioned yet. Waiting for commissioning.
Matter Node not commissioned yet. Waiting for commissioning.
...
Matter Node is commissioned and connected to the network. Ready for use.

Temperature Controlled Cabinet Configuration:
  Setpoint: 4.00°C
  Min Temperature: -10.00°C
  Max Temperature: 10.00°C
  Step: 0.50°C
Temperature setpoint updated to: 4.50°C (Range: -10.00°C to 10.00°C)
*** Temperature setpoint 4.00°C reached/overpassed while increasing ***
Temperature setpoint updated to: 5.00°C (Range: -10.00°C to 10.00°C)
Temperature setpoint updated to: 5.50°C (Range: -10.00°C to 10.00°C)
...
Current Temperature Setpoint: 6.00°C (Range: -10.00°C to 10.00°C)
...
*** Temperature setpoint 4.00°C reached/overpassed while decreasing ***
Temperature setpoint updated to: 3.50°C (Range: -10.00°C to 10.00°C)

Using the Device

Manual Control

The user button (BOOT button by default) provides manual control:

• Long press (>5 seconds): Factory reset the device (decommission)

Smart Home Integration

Use a Matter-compatible hub (like an Apple HomePod, Google Nest Hub, or Amazon Echo) to commission the device.

Apple Home

1. Open the Home app on your iOS device
2. Tap the "+" button > Add Accessory
3. Scan the QR code displayed in the Serial Monitor, or
4. Tap "I Don't Have a Code or Cannot Scan" and enter the manual pairing code
5. Follow the prompts to complete setup
6. The device will appear as a temperature controlled cabinet in your Home app
7. You can adjust the temperature setpoint within the min/max range

Amazon Alexa

1. Open the Alexa app
2. Tap More > Add Device > Matter
3. Select "Scan QR code" or "Enter code manually"
4. Complete the setup process
5. The temperature controlled cabinet will appear in your Alexa app
6. You can control the temperature setpoint and set up routines

Google Home

1. Open the Google Home app
2. Tap "+" > Set up device > New device
3. Choose "Matter device"
4. Scan the QR code or enter the manual pairing code
5. Follow the prompts to complete setup
6. The temperature controlled cabinet will appear in your Google Home app
7. You can control the temperature setpoint

Code Structure

The MatterTemperatureControlledCabinet example consists of the following main components:

1. setup(): Initializes hardware (button), configures Wi-Fi (if needed), sets up the Matter Temperature Controlled Cabinet endpoint with initial temperature configuration, and waits for Matter commissioning.

2. loop():

   • Dynamic Temperature Updates: Automatically changes the temperature setpoint every 1 second, cycling between the minimum and maximum temperature limits using the configured step value. This demonstrates the temperature control functionality and allows Matter controllers to observe real-time changes.
   • Setpoint Reached Detection: Monitors when the initial setpoint is reached or overpassed in each direction and prints a notification message once per direction.
   • Periodically prints the current temperature setpoint (every 5 seconds)
   • Handles button input for factory reset

3. Helper Functions:

   • initTemperatureControl(): Initializes the temperature control state from the current setpoint
   • checkSetpointReached(): Checks and logs when the initial setpoint is reached/overpassed
   • updateTemperatureSetpoint(): Updates the temperature setpoint with cycling logic and boundary detection
   • printTemperatureStatus(): Prints the current temperature status
   • handleButtonPress(): Handles button press detection and factory reset functionality

API Usage

The example demonstrates the following API methods:

• begin(tempSetpoint, minTemperature, maxTemperature, step) - Initialize the cabinet with temperature settings
• getTemperatureSetpoint() - Get current temperature setpoint
• setTemperatureSetpoint(temperature) - Set temperature setpoint (validated against min/max)
• getMinTemperature() / getMaxTemperature() - Get temperature limits
• setMinTemperature(temperature) / setMaxTemperature(temperature) - Set temperature limits
• getStep() / setStep(step) - Get/set temperature step value

Troubleshooting

• Device not visible during commissioning: Ensure Wi-Fi or Thread connectivity is properly configured
• Temperature setpoint not updating: Check Serial Monitor output to verify setpoint changes are being processed
• Setpoint out of range error: Ensure the setpoint is within the min/max temperature range
• Failed to commission: Try factory resetting the device by long-pressing the button. Other option would be to erase the SoC Flash Memory by using Arduino IDE Menu -> Tools -> Erase All Flash Before Sketch Upload: "Enabled" or directly with esptool.py --port <PORT> erase_flash
• No serial output: Check baudrate (115200) and USB connection

Related Documentation

• Matter Overview
• Matter Endpoint Base Class
• Matter Temperature Controlled Cabinet Endpoint

License

This example is licensed under the Apache License, Version 2.0.