W55RP20-EVB-PICO and AWS IoT MQTT Connectivity Issues

Question

I'm encountering difficulties establishing an MQTT connection between my W55RP20-EVB-PICO and AWS IoT, despite following the setup guide at https://docs.wiznet.io/Product/ioNIC/W55RP20/W55RP20-S2E/mqtt-connection-guide-en. Setup Details: Hardware: W55RP20-EVB-PICO with W55RP20-S2E_Bin_Files_V112.zip. Process: Firmware flashed, MAC address configured and verified via wizconfig, AWS IoT thing and certificates set up and downloaded. Configuration: MQTT settings applied using wizconfig_s2e_tool_1.5.6.3. Communication: Serial communication via DATA_TX (GP4) and DATA_RX (GP5) on the W55RP20-EVB-PICO. Observed Issue: No data exchange occurs during MQTT publish/subscribe tests within the AWS IoT test client. The AWS IoT test client's topic subscriptions do not receive messages from the W55RP20-EVB-PICO. Conversely, the W55RP20-EVB-PICO does not receive messages published from the AWS IoT test client. Switching between MQTT5 and MQTT3 protocols did not resolve the issue. Inquiry: What could be causing this communication failure, and what troubleshooting steps should I take?"

WIZnet AI assistant (automated answer) · Accepted Answer

Thank you for reaching out about your MQTT connection issues between the W55RP20-EVB-PICO and AWS IoT. Based on your detailed description, I can suggest several troubleshooting steps to help identify and resolve the communication failure. First, let's verify some key aspects of your setup: 1. Certificate Configuration: - Ensure all three certificate files (Root CA, Client Certificate, and Private Key) are properly loaded into the device - Verify the Root CA section is correctly configured in the Certificate Manager tab - Confirm you've pressed "Save to device" for each certificate and "Apply settings" afterward 2. MQTT Configuration: - Double-check that your Client ID matches exactly with the Thing name you created in AWS - Verify the endpoint URL is correctly copied from AWS IoT - Confirm port 8883 is being used for secure MQTT connections - Ensure the Topic paths are correctly formatted (e.g., $aws/things/your_thing_name/shadow/update) 3. Network Connectivity: - Verify the device has a stable network connection - Check if the device can successfully connect to other services or websites - Ensure no firewall is blocking outbound connections on port 8883 4. Specific Troubleshooting Steps: - Check the device's status indicators - does it show as connected to the MQTT broker? - Try simplifying your topic paths temporarily for testing - Monitor the serial output for any error messages during connection attempts - Verify AWS IoT policy permissions allow publish/subscribe on your topics - Try using the AWS IoT MQTT test client to both publish and subscribe to the same topic 5. Firmware Considerations: - Consider trying an older or newer firmware version if available - Ensure the firmware you're using (V112) fully supports MQTT with AWS IoT If these steps don't resolve the issue, please provide: - Any error messages you see in the serial terminal - Screenshots of your configuration settings - The exact topic strings you're using for publish/subscribe This will help us…