MatterPressureSensor
About
The MatterPressureSensor class provides a pressure sensor endpoint for Matter networks. This endpoint implements the Matter pressure sensing standard for read-only pressure reporting.
Features: * Pressure measurement reporting in hectopascals (hPa) * Read-only sensor (no control functionality) * Automatic pressure updates * Integration with Apple HomeKit, Amazon Alexa, and Google Home * Matter standard compliance
Use Cases: * Atmospheric pressure monitoring * Weather stations * Barometric pressure sensors * Pressure logging * Smart home weather monitoring
API Reference
Constructor
Initialization
begin
Initializes the Matter pressure sensor endpoint with an initial pressure value.
bool begin(double pressure = 0.00);
pressure- Initial pressure in hectopascals (hPa, default: 0.00)
This function will return true if successful, false otherwise.
Note: Typical atmospheric pressure at sea level is around 1013.25 hPa. Pressure values typically range from 950-1050 hPa.
Pressure Control
setPressure
Sets the reported pressure value.
bool setPressure(double pressure);
pressure- Pressure in hectopascals (hPa)
This function will return true if successful, false otherwise.
getPressure
Gets the current reported pressure value.
double getPressure();
This function will return the pressure in hectopascals (hPa).
Example
Pressure Sensor
// Copyright 2025 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/*
* This example is an example code that will create a Matter Device which can be
* commissioned and controlled from a Matter Environment APP.
* Additionally the ESP32 will send debug messages indicating the Matter activity.
* Turning DEBUG Level ON may be useful to following Matter Accessory and Controller messages.
*/
// Matter Manager
#include <Matter.h>
#if !CONFIG_ENABLE_CHIPOBLE
// if the device can be commissioned using BLE, WiFi is not used - save flash space
#include <WiFi.h>
#endif
// List of Matter Endpoints for this Node
// Matter Pressure Sensor Endpoint
MatterPressureSensor SimulatedPressureSensor;
// CONFIG_ENABLE_CHIPOBLE is enabled when BLE is used to commission the Matter Network
#if !CONFIG_ENABLE_CHIPOBLE
// WiFi is manually set and started
const char *ssid = "your-ssid"; // Change this to your WiFi SSID
const char *password = "your-password"; // Change this to your WiFi password
#endif
// set your board USER BUTTON pin here - decommissioning button
const uint8_t buttonPin = BOOT_PIN; // Set your pin here. Using BOOT Button.
// Button control - decommision the Matter Node
uint32_t button_time_stamp = 0; // debouncing control
bool button_state = false; // false = released | true = pressed
const uint32_t decommissioningTimeout = 5000; // keep the button pressed for 5s, or longer, to decommission
// Simulate a pressure sensor - add your preferred pressure sensor library code here
float getSimulatedPressure() {
// The Endpoint implementation keeps an uint16_t as internal value information,
// which stores data in hPa (pressure measurement unit)
static float simulatedPressureHWSensor = 950;
// it will increase from 950 to 1100 hPa in steps of 10 hPa to simulate a pressure sensor
simulatedPressureHWSensor = simulatedPressureHWSensor + 10;
if (simulatedPressureHWSensor > 1100) {
simulatedPressureHWSensor = 950;
}
return simulatedPressureHWSensor;
}
void setup() {
// Initialize the USER BUTTON (Boot button) that will be used to decommission the Matter Node
pinMode(buttonPin, INPUT_PULLUP);
Serial.begin(115200);
// CONFIG_ENABLE_CHIPOBLE is enabled when BLE is used to commission the Matter Network
#if !CONFIG_ENABLE_CHIPOBLE
// Manually connect to WiFi
WiFi.begin(ssid, password);
// Wait for connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println();
#endif
// set initial pressure sensor measurement
// Simulated Sensor - it shall initially print 900hPa and then move to the 950 to 1100 hPa as pressure range
SimulatedPressureSensor.begin(900.00);
// Matter beginning - Last step, after all EndPoints are initialized
Matter.begin();
// Check Matter Accessory Commissioning state, which may change during execution of loop()
if (!Matter.isDeviceCommissioned()) {
Serial.println("");
Serial.println("Matter Node is not commissioned yet.");
Serial.println("Initiate the device discovery in your Matter environment.");
Serial.println("Commission it to your Matter hub with the manual pairing code or QR code");
Serial.printf("Manual pairing code: %s\r\n", Matter.getManualPairingCode().c_str());
Serial.printf("QR code URL: %s\r\n", Matter.getOnboardingQRCodeUrl().c_str());
// waits for Matter Pressure Sensor Commissioning.
uint32_t timeCount = 0;
while (!Matter.isDeviceCommissioned()) {
delay(100);
if ((timeCount++ % 50) == 0) { // 50*100ms = 5 sec
Serial.println("Matter Node not commissioned yet. Waiting for commissioning.");
}
}
Serial.println("Matter Node is commissioned and connected to the network. Ready for use.");
}
}
void loop() {
static uint32_t timeCounter = 0;
// Print the current pressure value every 5s
if (!(timeCounter++ % 10)) { // delaying for 500ms x 10 = 5s
// Print the current pressure value
Serial.printf("Current Pressure is %.02fhPa\r\n", SimulatedPressureSensor.getPressure());
// Update Pressure from the (Simulated) Hardware Sensor
// Matter APP shall display the updated pressure percent
SimulatedPressureSensor.setPressure(getSimulatedPressure());
}
// Check if the button has been pressed
if (digitalRead(buttonPin) == LOW && !button_state) {
// deals with button debouncing
button_time_stamp = millis(); // record the time while the button is pressed.
button_state = true; // pressed.
}
if (digitalRead(buttonPin) == HIGH && button_state) {
button_state = false; // released
}
// Onboard User Button is kept pressed for longer than 5 seconds in order to decommission matter node
uint32_t time_diff = millis() - button_time_stamp;
if (button_state && time_diff > decommissioningTimeout) {
// Factory reset is triggered if the button is pressed longer than 5 seconds
Serial.println("Decommissioning Pressure Sensor Matter Accessory. It shall be commissioned again.");
Matter.decommission();
}
delay(500);
}