MQTT Unit

The MQTT Unit is an Ethernet communication module specifically designed for MQTT communication. It features an embedded W5500 Ethernet chip, which enables seamless connectivity to Ethernet networks. The module also includes a UART communication interface, allowing for control via AT commands. In addition, it integrates an RJ45 adaptive 10/100M network port for easy network connectivity.

Support the following products:

MqttUnit

Micropython Example:

import os, sys, io
import M5
from M5 import *
from unit import MQTTUnit
import time

def mqtt_0_SubTopic_event(data):
    global mqtt_0
    print(data[0])
    print(data[1])

mqtt_0 = MQTTUnit(port=(18, 17))

mqtt_0.set_client('m5-mqtt-2024', 'mqtt.m5stack.com', 1883, '', '', 120)
mqtt_0.set_subscribe('SubTopic', mqtt_0_SubTopic_event, 0)
mqtt_0.set_connect()

while True:
    mqtt_0.check_msg()
    time.sleep_ms(50)

UIFLOW2 Example:

example.png

mqtt_demo.m5f2

class MQTTUnit

Constructors

class MQTTUnit(port=(, ))

Create a MQTTUnit object

The parameters is:

  • port uart pin tuple, which contains: (tx_pin, rx_pin).

UIFLOW2:

init.png

Methods

MQTTUnit.set_client(client_id, server, port, username, password, keepalive)
Parameters:

  • client_id (str) – the unique client id string used when connecting to the broker.

  • server (str) – the hostname or IP address of the remote broker.

  • port (int) – the network port of the server host to connect to.

  • username (str or None) – a username for broker authentication.

  • password (str or None) – a password for broker authentication.

  • keepalive (int) – maximum period in seconds allowed between communications with the broker. If no other messages are being exchanged, this controls the rate at which the client will send ping messages to the broker.

UIFLOW2:

set_client.png

MQTTUnit.set_connect()

Connect to a server.

UIFLOW2:

set_connect.png

MQTTUnit.set_disconnect()

Disconnect from a server, release resources.

UIFLOW2:

set_disconnect.png

MQTTUnit.set_publish(topic, msg, qos=0)

Publish a message.

Parameters:

  • topic (str or bytes or bytearray) – the topic that the message should be published on.

  • msg (str or bytes or bytearray) – the message to send as a will.

  • qos (int) – the quality of service level to use

UIFLOW2:

set_publish.png

MQTTUnit.set_subscribe(topic, handler, qos=0)

Subscribe to a topic.

Parameters:

  • topic (str or bytes or bytearray) – a string specifying the subscription topic to subscribe to.

  • handler (function) – called when a message has been received on a topic that the client subscribes to and the message does match an existing topic filter callback.

  • qos (int) – the desired quality of service level for the subscription. Defaults to 0.

Note

  1. When using this block, the “MQTT connect” block must be set after this block

  2. The server can only subscribe to four topics at a time

UIFLOW2:

set_subscribe.png

An handler showing a message has been received:

def mqtt_0_SubTopic_event(data):
    print("topic:", data[0])
    print("msg:", data[1])

On uiflow2, you can get the topic and message of the current handler through get_topic.png and get_msg.png.

MQTTUnit.check_msg()

Important

check_msg() is “main loop iteration” methods, blocking and non-blocking version. They should be called periodically in a loop, check_msg() if you don’t have any other foreground tasks to perform (i.e. your app just reacts to subscribed MQTT messages).

Note that you don’t need to call check_msg() if you only publish messages.

check for a server message.

UIFLOW2:

check_msg.png

MQTTUnit.check_modem_is_ready()

To check whether the communication with the MQTT unit has been successful.

  • Return: bool: True or False

UIFLOW2:

modem_is_ready.png

MQTTUnit.get_firmware_version()

Get the current firmware version number.

  • Return: string

UIFLOW2:

get_firmware_version.png

MQTTUnit.get_baudrate()

Get the current baud rate of the module and the default baud rate is 9600.

  • Return: int: 4800, 9600, 19200, 34800, 115200, 230400

UIFLOW2:

get_baudrate.png

MQTTUnit.get_network_status()

To check whether the network status is connected or disconnected.

  • Return: int: 0 ~ 1

UIFLOW2:

get_network_status.png

MQTTUnit.get_network_parameters(param)

Get the current actual IP address, subnet mask, gateway and DNS server of the module.

The parameters is:

  • param: IP address = 0, subnet mask = 1, gateway = 2, DNS server = 3.

UIFLOW2:

get_network_parameters.png

MQTTUnit.get_mac_address()

Get the current MAC address of the module and MAC address the format is: XX-XX-XX-XX-XX-XX.

  • Return: string: “XX-XX-XX-XX-XX-XX”

UIFLOW2:

get_mac_address.png

MQTTUnit.get_static_ip(param)

Get the current actual IP address, subnet mask and gateway of the module.

The parameters is:

  • param: IP address = 0, subnet mask = 1, gateway = 2, DNS server = 3.

UIFLOW2:

get_static_ip.png

MQTTUnit.get_dhcp_status()

Get the inquire about enable/disable DHCP status

  • Return: int: 1: Enable, 0: Disable

UIFLOW2:

get_dhcp_status.png

MQTTUnit.set_dhcp_state(state)

Set the enable/disable DHCP

The parameters is:

  • state: Disable = 0, Enable = 1.

UIFLOW2:

set_dhcp_state.png

MQTTUnit.set_static_ip(ip, subnet, gateway)

Set the static IP address of the MQTT module.

Note

When the DHCP function is enabled, the static IP setting will not be enabled.

The parameters is:

  • ip: “xxx.xxx.xxx.xxx”

  • subnet: “xxx.xxx.xxx.xxx”

  • gateway: “xxx.xxx.xxx.xxx”

UIFLOW2:

set_static_ip.png