MQTT Communication with Mosquitto Broker (Non Secure MQTT, Port 1883)

Lab Objective:

In this lab, participants will explore the fundamentals of MQTT (Message Queuing Telemetry Transport) communication using the Mosquitto public broker at https://test.mosquitto.org on port 1883, with a PSoC6 board.

The PSoC-6 board connects to the internet through a Wi-Fi hotspot, publishes a message such as “TURN ON LED”, and the PSoC-6 board will subscribes to receive the message and turns on its LED.

🔥 Requirements

🚩 Let start

Create Application

Coding

1. Edit wifi_config.h

• Use your mobile hotspot as an access point. Edit “wifi_config.h” to match your mobile SSID setting:

  • #define WIFI_SSID “mobile_ssid”

  • #define WIFI_PASSWORD “password”

2. Edit file mqtt_client.h

Edit the following in “configs/mqtt_client.h”:

• MQTT_BROKER_ADDRESS to “test.mosquitto.org”

• Set the macros MQTT_PORT to 1883

• MQTT_SECURE_CONNECTION to 1

• MQTT_USERNAME to “” MQTT_PUB_TOPIC to “unique_topic”

• MQTT_SUB_TOPIC to “unique_topic”

• MQTT_SNI_HOSTNAME to “test.mosquitto.org”

3. Save the file

4. Build and Launch the Application

Open Putty, baud rate 115200

Result

• Press user button

• The GPIO interrupt service routine (ISR) notifies the publisher task.

• The publisher task publishes a message on a topic.

• The MQTT broker sends back the message to the MQTT client because it is also subscribed to the same topic.

• When the message is received, the subscriber task turns the LED ON or OFF. As a result, the user LED toggles every time the user presses the button.

🎉 Congratulations! You can now complete this lab

Supported toolchains (make variable 'TOOLCHAIN')

• GNU Arm® embedded compiler v10.3.1 (GCC_ARM) - Default value of TOOLCHAIN

• Arm® compiler v6.16 (ARM)

• IAR C/C++ compiler v9.30.1 (IAR)

Supported kits (make variable 'TARGET')

• PSoC™ 62S2 Wi-Fi Bluetooth® pioneer kit (CY8CKIT-062S2-43012)

• PSoC™ 62S1 Wi-Fi Bluetooth® pioneer kit (CYW9P62S1-43438EVB-01)

• PSoC™ 62S1 Wi-Fi Bluetooth® pioneer kit (CYW9P62S1-43012EVB-01)

• PSoC™ 62S3 Wi-Fi Bluetooth® prototyping kit (CY8CPROTO-062S3-4343W)

Related resources

Other resources

Infineon provides a wealth of data at www.infineon.com to help you select the right device, and quickly and effectively integrate it into your design.

Document history

Authors:

• Assoc. Prof. Wiroon Sriborrirux

• Mr. Sriengchhun Chheang

• Mr. Sabol Socare

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