Chengdu Ebyte Electronic Technology Co.,Ltd.
EBT3001 User Manual
Copyright ©2012–2022，Chengdu Ebyte Electronic Technology Co.,Ltd.
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Alibaba Cloud MQTT platform communication test:
4.3 Advanced Features
4.3.1 Random native port
TCP client, UDP client, HTTP client, MQTT client can configure the local port to 0 (use random local port), and server
mode cannot use random port, otherwise the client cannot establish a connection correctly.
Using a random port connection can quickly re-establish the connection when the device disconnects the server
unexpectedly, preventing the server from rejecting the connection due to four waves of incompleteness. It is
recommended to use a random port in client mode .
The device will automatically enable random ports when configuring the TCP client, HTTP client, and MQTT client
modes.
4.3.2 Heartbeat Packet Function
In client mode, users can choose to send heartbeat packets and set the time of heartbeat packets by themselves. The
heartbeat packet can be selected in two modes: network heartbeat packet and serial port heartbeat packet. It supports
hexadecimal and ASCII transmission. This heartbeat packet is not MQTT heartbeat and needs to be turned off in MQTT
client mode. MQTT heartbeat only needs to configure KeepAlive in "MQTT function settings" Time, it is recommended
not to configure less than 60s, for example, 120s is recommended in the Alibaba Cloud manual.
Heartbeat packet sending mode:
(1) The default is to turn off the heartbeat packet mode.
(2) Serial port mode -> The device sends heartbeat content to the serial bus according to the set heartbeat interval.
(3) Network port mode -> The device sends heartbeat content to the network port bus according to the set heartbeat
interval.
Customize heartbeat packet content (maximum support 40 bytes (ASCII) data, 20 bytes (HEX) data)
