RS485 TO ETH ( B)
Look at whether the monitoring computer and equipment are in the local network :
a) If the computer is a public IP server leased on the Internet, the device must use the TCP
client method to connect the device to the server. At this time, you can choose ② and ⑤ in
Table 6, if it is a multi-serial server, you must choose ⑤ .
b) If they are all on the local network (can ping each other), it depends on whether the host
computer actively inquires or the device actively sends data. If the device actively uploads, the
② method of using the device as a TCP client must be used, otherwise the ① method can be
selected.
5 . 2 . DIRECT TCP/ IP COMMUNICATION MODE
If Modbus TCP protocol conversion and virtual serial port are not needed, the user software
may directly communicate with the serial port server' s network port for TCP/ IP communication,
and the serial server converts TCP/ IP data into serial data and sends it to the serial device.
Generally, users of this kind of usage develop their own upper computer network
communication software, which integrates the analysis of the device's serial communication
protocol. This method is more flexible and efficient than the virtual serial port. Correspond to ⑥
and ⑦ in Table 6.
The section "4.5 TCP Communication Test" mainly briefly describes how to communicate
when the serial port server is used as a TCP server. Here will describe how TCP client, UDP mode,
and multiple TCP connections communicate with computer software. Among them, the
computer software takes SSCOM (serial port debugging, software that imitates user TCP/ IP
communication) as an example.
The serial server complies with the standard TCP/ IP protocol, so any network terminal that
complies with this protocol can communicate with the serial server. For two network terminals
(here, the network debugging tool and the serial server) to be able to communicate, their
parameter configuration must be paired.
5 . 2 . 1 . TCP CLIENT MODE
There are two working modes in TCP mode: TCP server and TCP client. Regardless of which
mode is adopted, one must be the server and the other must be the client. After that, the client
can access the server, both of which are either client or service. Communication cannot be
achieved at the end.
When the serial port server is used as a client, there must be three corresponding
relationships, as shown in Figure blow. (1 ) Working mode correspondence: The working mode of
the serial port server is the server mode of the client corresponding to the network tool, ( 2 ) IP
address correspondence: The destination IP of the serial port server must be the IP address of
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