Chengdu Ebyte Electronic Technology Co., Ltd.
NB1A1User Manual
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Chengdu Ebyte Electronic Technology Co., Ltd.
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4.4.7 Port Mapping
The port mapping function maps any serial port to implement data exchange between serial ports.
It is usually used when the parameters of the serial ports on both ends of the system are inconsistent.
After port mapping is enabled, other functions are unavailable.
4.5 Channel terminal
Random port
：
TCP clients, UDP clients, HTTP clients, MQTT clients can configure the local port to 0 (using
random local ports), server mode cannot use random ports, otherwise the client cannot establish a
connection correctly (the device is not listening to the port properly).
Random port connection can be quickly reestablished when the device disconnects the server
unexpectedly, preventing the server from rejecting the connection due to four incomplete waves. You
are advised to use random port in client mode.
The device automatically configures random ports when the TCP client, HTTP client, and
MQTT client modes are configured AT. You can cancel the configuration.
Static port
：
Device fixed port (factory default: 8001-8016), TCP server mode device listens to the
configuration port, receives the connection request from the client and establishes the connection for
data communication, TCP client mode device fixed port initiates the connection request.