PUSR USR-TCP232-302 User manual

USR-TCP232-30x Series User Manual
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Serial to Ethernet
(Cost effective)
Be Honest & Do Best
Your Trustworthy Smart Industrial IoT Partner
User Manual
USR-TCP232-302/304/306
V2.0

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Content
1. Introduction ...............................................................................................................................................- 4 -
1.1. Overview...........................................................................................................................................- 4 -
1.2. Features............................................................................................................................................- 4 -
2. Get Started.................................................................................................................................................- 5 -
2.1. Hardware interface introduction........................................................................................................- 5 -
2.1.1. Power supply...........................................................................................................................- 5 -
2.1.2. Serial port................................................................................................................................- 6 -
2.1.3. Ethernet port............................................................................................................................- 6 -
2.1.4. LED indicators..........................................................................................................................- 7 -
2.1.5. Reload button..........................................................................................................................- 7 -
2.1.6. Factory default setting .............................................................................................................- 8 -
2.2. Quick test..........................................................................................................................................- 8 -
2.2.1. Download software..................................................................................................................- 8 -
2.2.2. Hardware connection.............................................................................................................- 10 -
2.2.3. Parameter configuration ........................................................................................................- 10 -
2.2.4. Data transmission test............................................................................................................- 13 -
2.2.5. Technical support and assistance...........................................................................................- 14 -
3. Configuration and parameter details ........................................................................................................- 14 -
3.1. Web interface..................................................................................................................................- 14 -
3.1.1. Status .................................................................................................................................... - 15 -
3.1.2. IP settings.............................................................................................................................. - 17 -
3.1.3. Serial port settings ................................................................................................................. - 18 -
3.1.4. Expand function settings........................................................................................................- 20 -
3.1.5. Miscellaneous settings ...........................................................................................................- 22 -
3.2. Configuration software....................................................................................................................- 23 -
3.2.1. Search device ........................................................................................................................- 23 -
3.2.2. Parameter settings................................................................................................................. - 24 -
3.2.3. Open web server....................................................................................................................- 24 -
3.2.4. Firmware upgrade .................................................................................................................- 25 -
3.2.5. Restart the device ..................................................................................................................- 26 -
3.2.6. Restore to factory default settings ..........................................................................................- 26 -

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4. Operation mode....................................................................................................................................... - 27 -
4.1. TCP server.......................................................................................................................................- 27 -
4.2. TCP client ........................................................................................................................................- 28 -
4.3. UDP server ......................................................................................................................................- 30 -
4.4. UDP client .......................................................................................................................................- 32 -
4.4.1. Transparent data transmission............................................................................................... - 32 -
4.4.2. Broadcast ..............................................................................................................................- 33 -
4.4.3. Multicast ...............................................................................................................................- 34 -
4.5. HTTP client ......................................................................................................................................- 35 -
5. Modbus Gateway .....................................................................................................................................- 36 -
5.1. Modbus RTU to Modbus TCP.............................................................................................................- 36 -
5.1.1. Ethernet master with serial slave ............................................................................................ - 37 -
5.1.2. Serial master with Ethernet slave............................................................................................ - 38 -
5.2. Multi-host Modbus polling...............................................................................................................- 40 -
6. Additional features...................................................................................................................................- 41 -
6.1. Built-in webpage ............................................................................................................................- 41 -
6.1.1. Edit webpage file....................................................................................................................- 41 -
6.1.2. Upgrade the webpage file......................................................................................................- 41 -
6.2. Index function.................................................................................................................................- 42 -
7. Warranty.................................................................................................................................................. - 43 -
8. Contact Us................................................................................................................................................ - 43 -
9. Disclaimer................................................................................................................................................- 44 -

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1. Introduction
1.1. Overview
USR-TCP232-302, USR-TCP232-304 and USR-TCP232-306 are cost-effective serial to Ethernet converter. They
adopt Cortex-M0 solution, which has a main frequency up to 48MHz, providing fast transmission speed.
Equipped with RS232/RS485/RS422 serial port and 10/100M Ethernet port, those products can connect to variety
of serial devices to achieve transparent transmission via simple configuration to save manpower and shorten the
development cycle. These products are widely used in smart traffic, unattended Weighing, manufacturing
industry etc.
USR-TCP232-302, 304 and 306 are identical in software features, they both support transparent data
transmission, Modbus gateway, user-defined webpage, heartbeat packet, registration packet, index function etc.
In hardware, TCP232-302 is RS232 to Ethernet converter, TCP232-304 is RS485 to Ethernet, TCP232-306
supports RS485/RS232/RS422, but RS485/RS232/RS422 can’t work at the same time.
Table 1. Ordering Guide
Model
Description
USR-TCP232-302
1 x RS232, DB9 female, DC 5.5*2.1 power supply: 5~7 V
USR-TCP232-304
1 x RS485, 3P connector, DC 5.5*2.1 power supply: 5~7 V
USR-TCP232-306
1 x RS232/485/422, 4P connector + DB9 male, DC 5.5*2.1 & block terminal power
supply:5 ~ 36V
1.2. Features
•ARM core, Cortex-M0 solution, equipped with deeply optimized TCP/IP protocol stack. It has low latency
and strong scalability, stable and reliable.
•Supports custom webpage function to help users improve brand influence.
•1.5KV built-in network Magnetic Isolation.
•Wide baud rate: 600~460.8 Kbps, multiple parity bit: NONE, Odd, Even, Space, Mark
•Supports Modbus RTU to Modbus TCP protocol conversion and multi-host polling.
•Supports keepalive mechanism to quickly detect the dead connections and reconnect.
•Supports hardware and software watchdog, automatically restarts when the device goes down.
•10/100Mbps Ethernet port and support Auto MDI/MDIX.
•Supports a wide industrial operating temperature, -25℃~75℃.
•Versatile operation modes: TCP Server, TCP Client, UDP, HTTP client.
•Support virtual COM, COM Port Redirector USR-VCOM (windows).

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•Easy to config: built-in webpage and AT command to set parameters.
2. Get Started
2.1. Hardware interface introduction
2.1.1. Power supply
The USR-TCP232-302 and USR-TCP232-304 provide DC jack power supply interface. Power supply range:
5~7V DC.
Figure 1. TCP232-302/304 DC power supply
The USR-TCP232-306 provides 2-pin power supply terminal blocks and DC jack. The power supply support
anti-reverse protection. Power supply range: 5~36V DC.
Figure 2. TCP232-306 power supply

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2.1.2. Serial port
Table 2. Serial port pin description
Model
Type
Description
USR-TCP232-302
RS232, DB9 female
2: RxD
3: TxD
5: GND
USR-TCP232-304
RS485
A: Data+
B: Data-
USR-TCP232-306
RS232, DB9 male
2: TxD
3: RxD
5: GND
RS485/RS422
For RS485
A: Data+
B: Data-
For RS422
T+: Transmit data (+)
T-: Transmit data (-)
R+: Receive data (+)
R-: Receive data (-)
2.1.3. Ethernet port
USR-TCP232-30x series adopt 10Base-T/100Base-TX adaptive Ethernet RJ45 interface which supports
automatic MDI/MDIX connection.
Figure 3. RJ45 with light

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Table 3. Ethernet pin assignment
Pin number
Signal name
1
Send data+(TD+)
2
Send data-(TD-)
3
Receive data+(RD+)
6
Receive data-(RD-)
4, 5, 7, 8
Unused
2.1.4. LED indicators
In USR-TCP232-30x series, only USR-TCP232-306 has LED indicators. The LED indicators description is in the
following table.
Table 4. LED indicators description
LED name
Status
Description
Power
ON
Power supply is normal
OFF
No power supply or abnormal power supply
Work
Blinking
System is booted up and running
Link
ON
TCP connection is established, or the device works
in UDP mode
TX
Blinking
Serial port is transmitting data
RX
Blinking
Serial port is receiving data
2.1.5. Reload button
After the USR-TCP232-30x is powered on, keep pressing the reload button for 3~15 seconds and then release
to restore the 30x device to the factory default settings.

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Figure 4. Reload button
2.1.6. Factory default setting
The USR-TCP232-30x serial device server comes with the following default setting.
Table 5. Default parameter
Parameter
Default Values
Username
admin
Password
admin
Device IP
192.168.0.7
Subnet Mask
255.255.255.0
Gateway IP
192.168.0.1
COM port
115200, N, 8, 1
COM operation mode
TCP client
2.2. Quick test
USR-TCP232-30x series serial server has a built-in Web server, which provides a convenient way to access
and configure the serial server. Users can use Edge, Firefox or Google browser to access it. This chapter is a quick
introduction to the USR-TCP232-30x series of serial server products. It is recommended that users read this
chapter and follow the instructions once for the system, and you will have a basic understanding of the product.
For specific function details and instructions, please refer to the subsequent chapters.
2.2.1. Download software
Download the software from PUSR’s website:
Config software: 插入设置软件下载链接
Test software: https://www.pusr.com/support/download/usr-tcp232-test-V13.html
After downloading, run the config software. It is strongly recommended for the users to set the Network
Parameters through configuration tool first. Other device-specific configurations can later be carried out via
user-friendly Web-Interface.

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Figure 5. Config software
Figure 6. Test software

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2.2.2. Hardware connection
For fast networking of USR-TCP232-30x series serial server, you need to prepare a PC, a router, a serial server,
a network cable, a serial cable, and a DC5V/1A power supply. The hardware connection is shown in following
figure. To establish a TCP / IP network all devices must be connected to the same network either locally or via
gateway connections.
Figure 7. Hardware connection
2.2.3. Parameter configuration
Using the config software,
1. Users can search out the 30x device,
2. Set the IP type as DHCP/Auto IP,
3. Save config,
4. Search the device again,
5. Open the webpage，the user will be navigated to the login page, the username and password are both
“admin”.

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Figure 8. Search and basic settings
After entering the username and password, click "OK" and the server will authenticate. After success, you will
enter the main page of the Web server, as shown in the following figure.
Figure 9. Current status
In serial port page, set the remote IP to 172.16.11.31, then save parameters and restart the module.

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Figure 10. Serial port parameters
After restarting, check the parameters via the config software. Form the picture, we can see the parameters has
already taken effect.
Figure 11. Parameters checking via config software
The IP address of the PC must be modified to ensure that it is in the same local area network as the IP of the
serial server if you want to connect 30x to PC directly via a net cable. The default IP address of serial server is:
192.168.0.7. Set the PC's IP address as: 192.168.0.X (X is any valid value from 2 to 253 except 7). The specific

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Windows system operation page is shown in the following figure. you can access the Web page of the USR-
TCP232-30X series serial server through browser as mentioned above.
Figure 12. IP setting of PC
2.2.4. Data transmission test
Run the test software on the PC, set the protocol as TCP Server, local IP keep the same with the remote IP of
30x device, local host port keeps the same with the remote port of 30x device. After the TCP connection is
established, users can check the link indicator, it will keep steady on.
In this test, we use the default serial port parameters (115200, N, 8, 1) to test. Users can also to modify the
baud rate, data bit and other parameters of the serial port via webpage or config software as needed.
The following picture shows an example of parameters setting to test transparent transmission.

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Figure 13. Data transmission test
2.2.5. Technical support and assistance
Please visit the USR IoT website: https://www.pusr.com where you can find the latest information about the
product. Contact your distributor, sales representative, or PUSR's support center:
http://h.usriot.com/index.php?c=frontTicket&m=sign for technical support if you need additional assistance.
Please have the following information ready before you submit a ticket:
–Product model
–Description of your peripheral attachments
–Description of your software (firmware version, application, function description, etc.) –A complete
description of the issue and steps to reproduce
3. Configuration and parameter details
3.1. Web interface
Every USR-TCP232-30X Industrial Serial Device Server is equipped with a built-in web server in the firmware.
Therefore, the device can be accessed by using a web browser for configuring by entering the device’s IP address
in the URL field of your web browser. An authentication will be required and you will have to enter the username
(Default value is “admin”) and password (Default value is “admin”) for accessing the web interface as shown

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in Figure 14. This approach (web interface) for configuring your device is the most user-friendly. It is the most
recommended and the most common method used for USR-TCP232-30X Serial Device Server Series. Please go to
its corresponding section for a detailed explanation
Figure 14. Login page
3.1.1. Status
After entering the correct username and password and the authentication is successful, you will enter the
main page of the Web, as shown in figure 15. The main page can be roughly divided into three areas. The upper
area displays the logo, the lower left area is the function menu area, the middle area is the main function display
area, and the lower right area is the help document area. Figure 15 illustrates the status page of the web
interface.

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Figure 15. Current status
The function of the device status part is to display some specific information of the current device, including
module name, IP address, MAC address, etc.
Table 6. Description of Current status
Parameter Item
Description
Module name
The name of the serial server, which can be customized by the user on the "Miscellaneous
settings" page.
IP address
The IP address of the serial server.
MAC address
The MAC address of the serial server.
Remote IP/TX/RX
IP：The IP of remote host, it displayed once the TCP connection is established,
Tx: The data count from serial to network
Rx: The data count from network to serial
When the TCO232-30X work in TCP server mode, the page can display up to 5 connection
information.

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3.1.2. IP settings
You must assign a valid IP address to the USR-TCP232-30x before it will work in your network environment.
The IP address must be unique within the network. If the device is connected to the Internet and should connect
to other servers over the Internet to get some services such as Network Time Protocol (NTP) server, you will
need to configure the DNS server to be able to resolve the host name of the NTP server. The detailed
description of the configuration parameters on this interface is shown in Table 7.
Figure 16. IP settings
Table 7. Detail description of IP settings
Parameter Item
Description
IP type
DHCP: To obtain required TCP/IP configuration information from router.
Static IP: User need to set the IP information manually.
IP address
IP address is a 32-bit address assigned to devices connected to the Internet. The IP
address consists of two fields: the network number field (Net-id) and host number field
(host-id). In order to facilitate the management of IP addresses, IP addresses are
divided into five categories: Class A, B, and C addresses are unicast addresses, Class D
addresses are multicast addresses, Class E addresses are reserved addresses for future
special purposes. The IP addresses currently in large numbers belong to three types of
addresses: A, B, and C.

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Subnet mask
The mask is a 32-bit number corresponding to an IP address. Some of these numbers
are 1, and the others are 0. The mask can divide the IP address into two parts: the
subnet address and the host address. The part of the IP address corresponding to the 1
bit in the mask is the subnet address, and the other bits are the host address. The mask
for class A addresses is 255.0.0.0, the mask for class B addresses is 255.255.0.0, the
mask for class C addresses is 255.255.255.0.
Default gateway
The default gateway in the host is usually called the default route. The default route
(Default route) is the route chosen by the router when no other route exists for the
destination address in the IP packet. All packets whose destination is not in the router's
routing table will use the default route.
DNS
The IP address of the DNS server.
When users need to access information online through domain name, like
www.pusr.com. DNS translates domain names to IP so browsers can load Internet
resources.
3.1.3. Serial port settings
The main function of the serial device server is to carry out two-way transparent transmission of standard
serial bus data (RS-232, RS-485, RS-422) and standard Ethernet data supporting TCP/IP protocol to solve
common serial equipment Networking problems on the Internet. The Port configuration page can configure the
parameters of the serial port and socket, as shown in following picture.

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Figure 17. Settings of serial port
Details on work mode connectivity protocols and its settings of TCP232-30X series are given in Chapter 4
Operation modes, this section will only focus on the part of parameter description. The description of the
configuration parameters on this interface is shown in Table 8.
Table 8. Detail description of serial port
Parameter Item
Description
Baud rate
This sets the port’s data transfer speed. Choices are from 600—230400. Set this to
match the baud rate setting of the connected device. Default is 115200.
Data size
This sets the number of bits used to transmit one character of data. Choices are: 7 and
8. Set this to match the data bit setting of the connected device. Default is 8 (which is
the default for the majority of serial devices).
Parity bits
This bit checks the integrity of the transmitted data. Choices are: None, Odd, Even. Set
this to match the parity setting of the connected device. Default is None (which is the
default for the majority of serial devices).
Stop bits
This indicates that a character has been transmitted. Set this to match the stop bit

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setting of the connected device. Choices are: 1 and 2. Default is 1 (which is the default
for the majority of serial devices).
Local Port Number
When TCP232-30X work in TCP server mode, the local port is the listening port.
Remote Port Number
When TCP232-30X work in TCP client mode, the remote port is the target port to
connect to.
Work mode
Please to check Chapter4 for more information.
Remote Server Addr
When TCP232-30X work in TCP client mode, the remote server address is the target
address to connect to.
RESET
This function is available in TCP client mode. The 30X device connect to TCP server
actively when works as TCP client. The 30X device will restart if the TCP connection
is not established after 30 attempts.
The Reset function is mainly used to initialize the 30X device by restarting when
the 30X program runs out or crashes and counter abnormal TCP connection. Then
to restore the 30X to normal operation under certain conditions.
LINK
The LINK indicator works only after the LINK function is enabled.
INDEX
See more information in chapter 6.1.1.
Similar RFC2217
Enabling this function allows users to use customized RFC2217 commands on the
network to dynamically modify the serial port's baud rate, data bits, stop bits, and
parity bits. This function is only allowed when the working mode is TCP Server and
TCP Client. Note that this protocol is used to change the serial port parameters of
TCP232-30X.
Tcp Quick Ack
3.1.4. Expand function settings
USR-TCP232-30X series provide rich additional function which is displayed in this function tab page. The
function detail information will be described in the following table, some more important function is introduced
in relevant chapters.