USC520 / USC540 User Manual www.usconverters.com
U.S. Converters LLC 12 / 52 Copyrights © U.S.
Converters
3.1.2. TCP Server Mode
1) Different from UDP, in this mode, connection has status of disconnected and active. Connection is
still active although USC520/USC540 does not send data.
2) USC520/USC540 listens to local port set firstly, respond and build connection when there is a
connection request. Serial port will send data to all client which connected with USC520/USC540 at
the same time once serial port received data.
3) It supports USR Synchronous baud rate (Similar RCF2217), which can revise USC520/USC540
serial parameter as baud rate accordingly. This function should be combined with USR-VCOM.
4) It support 8 clients connections at max. (32 clients will be improved in the following.)
5) Support Modbus TCP function.
6) Under TCP Server mode, USC520/USC540 listens to local port actively and will not monitor
connected IP and port. When the 9
th
client is connected, the oldest one will be ticked.
3.1.3. UDP Client Mode
1) It subjects to UDP protocol, no connection, just only sending data.
2) USC520/USC540 only communicates with destination port of IP. Otherwise, the data cannot be
received.
3) Under this mode, destination Address is 255.255.255.255, then it can make UDP broadcast and
receive broadcast data. Broadcast within segment as 192.168.0.255, it can be sent but cannot be
received currently.
4) Under UDP Client/ UDP Server mode, host PC allow data length 1460 bytes at max to
USC520/USC540.
3.1.4. UDP Server Mode
1) Based on normal UDP, it doesn't verify source IP address. Every time USC520/USC540 receives
one UDP data packet, it changes destination IP to where data comes and it sends the data to the IP
and port which communicate latest.
