Mitsubishi Electric MELSEC iQ-F Series User Manual page 53

• When receiving messages from a broker
FX5 CPU module
(ladder program)
SUBSCRIBE request
FB: MQTT_Subscribe FB: MQTT_Subscribe
i_bSubscribe=OFF→ON i_bSubscribe=OFF→ON
FB: MQTT_Subscribe: output FB: MQTT_Subscribe: output
o_bOK=ON o_bOK=ON
PUBLISH message receive
(when there is no receive data)
FB: MQTT_Receive FB: MQTT_Receive
i_bEN=OFF→ON i_bEN=OFF→ON
FB: MQTT_Receive: output FB: MQTT_Receive: output
o_bOK=ON o_bOK=ON
o_uReceiveTopicSize=0 o_uReceiveTopicSize=0
o_uReceiveMessageSize=0 o_uReceiveMessageSize=0
PUBLISH message receive
(when there is receive data)
FB: MQTT_Receive FB: MQTT_Receive
i_bEN=OFF→ON i_bEN=OFF→ON
FB: MQTT_Receive: output FB: MQTT_Receive: output
o_bOK=ON o_bOK=ON
o_uReceiveTopicSize = 1 or more
o_uReceiveMessageSize = 1 or more
Subscribing processing
UNSUBSCRIBE request
FB: MQTT_Subscribe FB: MQTT_Subscribe
i_bUnSubscribe=OFF→ON i_bUnSubscribe=OFF→ON
FB: MQTT_Subscribe: output FB: MQTT_Subscribe: output
o_bOK=ON o_bOK=ON
Ethernet module
SUBSCRIBE (Topic) SUBSCRIBE (Topic)
SUBACK SUBACK
PUBLISH (Topic, Data) PUBLISH (Topic, Data)
UNSUBSCRIBE (Topic) UNSUBSCRIBE (Topic)
UNSUBACK UNSUBACK
PUBLISH PUBLISH
Cloud
Broker
PUBLISH (Topic, Data) PUBLISH (Topic, Data)
*QoS=0 *QoS=0
PUBLISH (Topic, Data) PUBLISH (Topic, Data)
*QoS=0 *QoS=0
IoT
Device
Publisher
4 FUNCTION LIST
51
4.3 Other Functions
4