Smart-Blinds_Arduino-Nano-Matter

Transform your home into a seamless smart environment with an Arduino Nano Matter-powered roller blind system. Learn how to automate blinds through Alexa, gather sensor data with Home Assistant, and create a monitoring dashboard with Arduino Cloud.

DEBUGGING TIPS

Matter Library Debugging Strategy

When working with Arduino Matter libraries, compiling the sketches can be time-consuming. To streamline the process, we recommend initially commenting out or excluding the Matter libraries until you are confident the core functionality of your code is working as expected. In our approach, we first tested individual components—starting with the built-in LED on the Nano Matter board, followed by the stepper motor, the illuminance sensor, the temperature sensor, and the distance sensor. Once we confirmed that each device was functioning correctly, we integrated the Matter libraries and proceeded with debugging. This staged approach helps isolate issues and saves time during the compilation process.

Connecting to Alexa - Key Troubleshooting Steps

If you encounter difficulties connecting the Arduino Nano Matter board to the Alexa app, follow these troubleshooting steps to resolve the issues:

• Decommission the Matter device: If your device was previously commissioned, ensure you upload code to decommission it. This is crucial for resetting the connection.

• Burn the bootloader: After decommissioning, use the Silicon Labs Simplicity Bootloader to burn the bootloader onto the board.

• Reset the Amazon Echo: Before reconnecting the Arduino board to the Alexa app, reset your Echo hub to renew the connection.

• Reconnect to Alexa: If the device still fails to connect, repeat steps 1–3, as missing any step can prevent successful pairing.

• Network credentials: If the Alexa app prompts you for network credentials, this likely means the device was not fully decommissioned. Follow the decommissioning steps again.

Note: The Matter-generated code for your device remains the same regardless of resetting or re-uploading. Once the QR code is generated, you can save and reuse it, as it will be associated with your specific Arduino Nano board.

Design Tip for I²C Sensors

If you choose different sensors than those used in this project and they lack documentation, you can create an I²C scanner sketch like the following to identify their addresses. If the scanner returns multiple addresses, it’s often due to improperly soldered pins or floating connections. Additionally, verify if your sensors require external pull-up resistors. For example, in our project, the temperature sensor's SDA channel required a 4.3kΩ pull-up resistor between VDD and SDA, which significantly improved reading consistency.

#include <Wire.h>

void setup() {
  Wire.begin();
  Serial.begin(9600);
  while (!Serial); // Wait for Serial Monitor to open
  Serial.println("I2C Scanner");
}

void loop() {
  byte error, address;
  int nDevices = 0;

  Serial.println("Scanning...");

  for (address = 1; address < 127; address++) {
    Wire.beginTransmission(address);
    error = Wire.endTransmission();

    if (error == 0) {
      Serial.print("I2C device found at address 0x");
      if (address < 16) Serial.print("0");
      Serial.print(address, HEX);
      Serial.println("  !");
      nDevices++;
    } else if (error == 4) {
      Serial.print("Unknown error at address 0x");
      if (address < 16) Serial.print("0");
      Serial.println(address, HEX);
    }
  }
  
  if (nDevices == 0)
    Serial.println("No I2C devices found\n");
  else
    Serial.println("Done\n");

  delay(5000); // Wait 5 seconds for next scan
}

Stepper Motor Control with TMC2209

For the TMC2209 driver we used, the motor current is regulated by adjusting the screw on the top-right corner of the board. Ensure that all pins are properly connected, as we found that the 5V input for the internal logic of the TMC2209 was not connected, preventing the stepper motor from functioning correctly. To identify the correct motor wiring, use a multimeter to check continuity between motor wires. If the multimeter beeps, those two wires should be connected to the A1 and A2 (or B1 and B2) pins on the TMC2209. Incorrect wiring may result in the motor vibrating without rotation or not functioning at all.

Sensor Address Verification

Always verify that you are using the correct addresses for the illuminance, distance, and temperature sensors. This will prevent issues during communication and ensure proper sensor functionality.