SIM800_MQTT

AutoConnect CallBack function

• Use this function if you want to use autoconnect(and auto reconnect) facility
• This function is called whenever TCP connection is established (or re-established).

connect function

• This function can be used to connect your client to MQTT broker.
• Use only if you do not use Auto connect functionality.
• Optionally you can use username, password, WILL topic and WILL Message.

OnConnect CallBack function

• This call back function is called when MQTT connection is established.
• You can call subscription and publish functions inside it (according to your need).

Publish function

• This function can be used to publish messages to different topics.
• You can select QoS levels and RETAIN flag according to your need.

Subscribe function

• This function can be used to subscribe messages from different topics.

OnMessage CallBack function

• This callback function is called when messages are received from subscribed topics
• Topic, TopicLength, Message, MessageLength are the arguments of OnMessage callback function.
• Inside this, you can write your custom code.

unsubscribe function

• This function can be used to unsubscribe from a previously subscribed topic.

disconnect function

• This function can be used to disconnect your client from MQTT broker.

available function

• return true when connection with mqtt brocker is existing

Other Features :

• You can specify your KeepAlive duration while initializing.
• Ping requests are sent and received automatically.
• QoS 0,1,2

Note:

Use the examples as a template.

To Do:

• [ ] Move the functions Autoconnect, OnConnect and OnMessage to the source code
• [ ] Implement a generic way to include external functions and their parameters to the funtions AutoConnect and OnConnect
• [ ] Change the function OnMessage to be a callback