RS232/422/485 Universal Device Servers are devices that allow serial devices to communicate over Ethernet networks. They convert serial signals into Ethernet packets and vice versa. RS232 is a standard for the serial communication transmission of data, while RS422 and RS485 are standards for the serial communication transmission of data in a differential signal.
These device servers can provide remote access and control of serial devices such as modems, printers, and sensors. They can support multiple serial interfaces and provide features such as network connectivity, security, and management. They are commonly used in industrial automation, building automation, and other applications that require remote monitoring and control of serial devices.
Contents
- Product Overview
- Product parameters
- Product specification
- 4. Quick start
- 5. Product features
- 6. common problems
Product Overview
1.1 product introduction
The RS232/485/422-ETH module is a composite serial server, which not only has the function of a conventional serial server but also converts the standard RS-232/422/485 serial signal into TCP/IP signal, realizing the two-way data transparent transmission between RS-232/422/485 serial port and TCP/IP network interface. At the same time, it has the function of Modbus Gateway, realizes the conversion between Modbus CP and Modbus RTU, makes the serial port equipment have the function of TCP/IP network interface, connects local area network for data communication, greatly reduces the wiring engineering of serial port equipment, and is easy to maintain, and extend communication patterns and distances.
1.2 Features
- Modbus TCP to Modbus RTU, realizing the communication between Ethernet Modbus TCP Master Station Equipment and serial Port Modbus RTU slave station equipment.
- Modbus RTU to Modbus TCP, realizing the communication between the Serial Port Modbus RTU master station equipment and Ethernet Modbus slave station equipment.
- Web configuration parameters, convenient and fast; web configuration of different slave properties, modified 485 communication parameters and network parameters
- Independent TCP to RS485 transmission; communication parameters can be set through the web page; module as a server.
- Independent TCP to RS232 transmission; communication parameters can be set through the web page; module as a server.
- Independent TCP to RS422 transmission; communication parameters can be set through the web page; module as a server.
1.3 application scenarios
RS232/485/422-ETH can be widely used in industrial automation, PLC control, building automation, POS system, power monitoring, access control medical, attendance system, self-service banking system, Telecom Equipment Room Monitoring, information appliances, LED information display equipment, measuring instruments and environmental power monitoring system, etc. RS232/422/485 serial port equipment or systems.
Product parameters
COM1(RS485 communication parameter)
Support function | Modbus RTU to Modbus TCP Modbus TCP to Modbus RTU 485 and net mouth transmission |
Interface type | RS485, Stud Terminal |
Baud rate | 9600 ~ 115200(default baud rate 9600) |
Communication format | Modbus RTU; 8-bit data, 1-bit stop, no check (configurable) |
Transmission distance | 1,200 meters |
COM2(RS422 communication parameter)
Support function | TCP to RS422 transmission |
Interface type | RS485, Stud Terminal |
Baud rate | 9600 ~ 115200(default baud rate 9600) |
Communication format | Default: 8-bit data, 1-bit stop, no check (configurable) |
Transmission distance | 1,200 meters. Baud rate 9600 |
COM3(RS232 communication parameter)
Support function | TCP to RS232 transmission |
Interface type | RS232, DB9 terminal header |
Baud rate | 9600 ~ 115200(default baud rate 9600) |
Communication format | Modbus RTU; 8-bit data, 1-bit stop, no check (configurable) |
Ethernet interface parameters
Interface form | RJ45 |
Communication Protocol | Modbus TCP; TCP; HTTP; |
Rate | 10 Mbps; full duplex |
Modbus TCP parameters
Default IP | 192.168.1.15 |
Default port | 502 |
Power parameter
Operating voltage | DC 9V ~ 24V; with protection against reverse connection |
Power consumption | 0.5 W ~ 2W |
Working Environment
Operating temperature | 20 °C ~ + 70 °C |
Storage temperature | 40 °C ~ + 85 °C |
In the news
Installation Mode | Guide rail |
Dimensions | 96 * 60 * 25(L * W * H overall size) |
Product specification
3.1 Installation dimensions

3.2 interface specification

3.2.1 terminal definition
Function | Name | Instruction |
Power supply | VCC | 24V DC power supply Positive |
GND | 24V DC power supply Negative | |
RS422 | R + | Module RXD + (RS422), connected to 422 communication device TXD + |
R – | Module RXD-(RS422), connect 422 communication equipment txd – | |
T + | Module TXD + (RS422), connected to 422 communication device RXD + | |
T-minus | Module txd-(RS422), connect 422 communication equipment RXD- | |
RS485 | A | A (RS485) |
B | B (RS485) |
3.2.2 RS232C interface description

Pin sequence | PIN action | Pin name |
1 | Data carrier detection | DCD |
2 | (module) data reception | Rxd |
3 | (module) data transmission | TXD |
4 | Data terminal preparation | DTR |
5 | GND | GND |
6 | Data Equipment Preparation | DSR |
7 | Request send | RTS |
8 | Clear send | CTS |
9 | Ringing’s instructions | Ri |
3.2.3 Light instructions
Name | Function | Instruction |
PWR | Power Indicator | The green light is always on, indicating that the power supply is normal |
SYS | System light | ● Flash Mob: Network interface and 485 data normal exchange ● One second on, one second off Establish connection no data interaction ● One flash per second: 485 communication anomaly, no slave data set ● Long time on: Idle State, no 485 communication, no Modbus TCP Make the connection ● Out in 5 seconds: Resetting |
232 | 232, Comms Light | ● Flicker: Establish a TCP connection under the serial port or network port that has a data transceiver ● Long time on: Just establish a TCP connection with no data interaction ● Put Out: No data interaction, no TCP connection established |
422 | 422, Comms Light | ● Flicker: Establish a TCP connection under the serial port or network port that has a data transceiver ● Long time on: Just establish a TCP connection with no data interaction ● Put Out: No data interaction, no TCP connection established |
485 | 485 communication light | ● Flicker: Establish a TCP connection under the serial port or network port that has a data transceiver ● Long time on: Just establish a TCP connection with no data interaction ● Put Out: No data interaction, no TCP connection established |
3.2.4 reset function
After normal power, long press the reset button for 5 seconds, and release in 2 seconds, Sys indicator lights off for 5 seconds to restore normal light means a successful reset, and then power off the restart module. After the Reset, the system parameters are restored to the default state, as explained below:
✓The serial port parameters of RS485/232/422 are 9600,8, NONE, 1; the TCP communication mode of RS485 is Server
✓ This machine is IP 192.168.1.15, subnet mask 255.255.255.0, Gateway 192.168.1.1
✓ The remote host IP is 192.168.1.124, and the remote host IP port number is 8080
✓ Web login password is 123456
4. Quick start
This chapter is a quick introduction to the RS232/485/422-ETH module. Users will have a systematic understanding of this module after learning the contents of this chapter. Please refer to other chapters for more details.
4.1 How to connect
4.1.1
The power supply of the module uses screw terminals. First, select the correct DC power supply whose working voltage and current are by the electrical parameters of the module. Then connect the positive and negative poles of the power supply to the + and-terminals of the module respectively, pay attention to the positive and negative power supply, do not connect the reverse. The module power supply has the function of an anti-reverse connection to prevent damage to the module caused by the positive and negative poles of the reverse connection power supply.
4.1.2 serial connection
There are three kinds of RS485/232/422 serial port signals in the module, among which RS232 adopts DB9 header, RS485/422 adopts screw terminal, and the connection is made according to the interface instruction in chapter 3.2. Attention should be paid to the data transmission and reception between the module and the equipment. When RS485 is connected to Modbus RTU slave station equipment, the bus form of hand-in-hand should be adopted.
4.1.3 internet connection
The RJ45 bus is used for the module network interface. The user needs to connect the Ethernet device with a 10MBPS network cable (through the switch/router). Today’s Ethernet devices support Ethernet port automatic jumper, you can directly use the network cable and Ethernet device connection.
If the Ethernet device connected to this module does not support automatic polarity switching, you will need to use cross wires, which are made as follows:
I. The T568A standard describes the order of lines from left to right:
1-green white (the outer layer of green has some white, which is the same group of lines as green)
2.-green
3-orange white (orange with some white on the outer layer, the same set of lines as orange)
4-.-blue
5–bluish white (blue with some white on the outer layer, the same set of lines as blue)
6-.-orange
7–brownish-white (the outer layer of brown has some white, which is the same set of lines as Brown)
8-.-brown
II. The T568B standard describes the order of lines from left to right:
1–orange white (orange with some white on the outer layer, the same set of lines as orange)
2–orange
3–green white (green with some white on the outer layer, and green is the same group of lines)
4–blue
5–bluish white (blue with some white on the outer layer, the same set of lines as blue)
6–green
7–brownish-white (the outer layer of brown has some white, which is the same set of lines as Brown)
8–brown

4.2 Ethernet to RS485 communication
Module RS485 supports Modbus TCP to Modbus RTU, Modbus RTU to TCP, and TCP to RS485 transmission three communication modes, and factory default communication mode.
Before MODUBS switches to Modbus RTU communication, the module RS485 interface should be connected to the serial port equipment RS485, and the module network interface should be connected to the Ethernet equipment through the network line (wiring reference section 4.1.2) to complete the hardware connection. Then log on to the module IP page and view or configure the module’s serial port parameters and IP (operations refer to Section 5.1.2) to ensure that the Ethernet device segment is consistent with the module and does not conflict with IP, and the communication parameters of the serial device are consistent with the module. The Modbus TCP message format is referred to in section 5.1.2.
For the other two modes of communication, it is first necessary to switch the mode through the web page configuration and then to ensure that the device and module network parameters, and serial port parameters match (refer to section 5.2.2 or section 5.6.2 for specific operations).
4.3 Ethernet to RS232/RS422 communication
This module can realize the transmission of TCP data between RS232/RS422 serial port equipment and Ethernet equipment. Before communication, the module RS232/RS422 interface should be connected with the corresponding serial port equipment and the module network interface with Ethernet equipment (connection reference section 4.1.2).
Then through the module IP page, ensure that the device and module serial port and network parameters match (specific Operation Reference Section 5.4.2 or Section 5.5.2).
5. Product features
5.1 Modbus TCP to MODBUS RTU communication mode
The request of Modbus TCP is directly converted into a Modbus RTU request and sent to the slave station through the RS485 port, then the corresponding slave station data is converted into a Modbus TCP message and sent to the host computer.

5.1.1 Modbus TCP to Modbus RTU communication mode parameters
Parameter type | Detail |
Default module IP | 192.168.1.15 |
Default Module Port | 502 |
Number of supported connections | 1 |
Native TCP Mode | Server |
RS485 communication parameter | Line 2: A to the 485 bus B-minus on 485 bus Default communication parameters: Baud rate: 9600,8-bit data, no parity, 1-bit stop, web configurable |
5.1.2 Modbus TCP to Modbus RTU mode configuration
Step 1: Open the web page and go to the “Parameter configuration” screen. See section 5.3, “Page configuration parameters” for details
Step 2: select the 485 parameters as “Server”, as shown in the following figure

Step 3: configure the module’s IP and gateway on demand, as shown in the following figure

Step 4: Configure Module RS485 serial port parameters according to requirement, refer to section 5.3.2 for detailed operation
Step 5: Power Off and Restart the module
5.1.3 Modbus TCP message format
(1) Digital Input Signal Acquisition Command
Protocol statement
Function code: 0x02
Discrete input register 0x00-0x15 corresponds to input channels 1-16;
When the input port state is invalid, the indicator light goes out and returns to 0; when valid, the indicator light turns on and returns to 1;
Read the format description of the discrete input request message
Read discrete INPUT REQUEST -MODBUS TCP TCP packet format)
Serial number | Message Field | Length (bytes) | Bytes, storage mode | Instruction |
1 | Transaction identification | 2 | High Byte first | It’s usually a message serial number |
2 | Protocol identification | 2 | The default is 0000 | |
3 | Message length | 2 | High Byte first high Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x02 | The related function code of the Modbus communication protocol |
6 | Starting address | 2 | High Byte first | |
7 | Number of registers | 2 | High Byte first |
Read the format specification for discrete input reply messages
Read the discrete input reply (Modbus TCP message format)
Serial number | Message Field | Length (bytes) | Bytes, storage mode | Instruction |
1 | Transaction identification | 2 | High Byte first | Usually, a message serial number is the same as the request message |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x02 | The related function code of the Modbus communication protocol |
6 | Data Length | 1 | The data length is N bytes, and the data length value is n | |
7 | data | N | Low byte in front, high bit per byte, in front | 8-bit discrete input per 1 byte |
Example message description
Read out the input status of channels 1-16, only channel 7 is valid in the example Request message: 00 06 00 00 00 06 01 02 00 00 00 10 00060000000601020000010 Reply message 00 06 00 00 00 05 01 02 02 40 00 0006000000050102024000
(2) Digital output signal acquisition command
Protocol statement
Function code: 0x01
Discrete output register 0x00-0x015 corresponds to output channel 1-16; this instruction is used to read the current coil register state.
When the output state is invalid, the indicator light goes out and returns to 0; when valid, the indicator light comes on and returns to 1;
Description of a request message format for reading discrete output status
Read coil status request
Serial number | Message Field | Length (bytes) | Bytes, storage mode | Instruction |
1 | Transaction identification | 2 | High Byte first | It’s usually a message serial number |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x01 | The related function code of the Modbus communication protocol |
6 | Starting address | 2 | High Byte first | |
7 | Number of registers | 2 | High Byte first |
Description of the format of the read coil output reply message
Read coil status response
Serial number | Message Field | Length (bytes) | Bytes, storage mode | Instruction |
1 | Transaction identification | 2 | High Byte first | Usually, a message serial number is the same as the request message |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x01 | The related function code of the Modbus communication protocol |
6 | Data Length | 1 | The data length is N bytes, and the data length value is n | |
7 | Data | N | Low byte in front, high bit per byte, in front | 8-bit discrete output per 1 byte |
Example message description Read out the output status of channels 1-16. Only channels 2 and 13 are valid in the example Request message: 00 01 00 00 00 06 01 01 00 00 00 10 Reply message 00 01 00 00 00 05 01 01 02 02 10
(3) Digital output signal single control command
Protocol statement
Function code: 0x05
Discrete output register 0x00-0x15 corresponds to output channel 1-16; this instruction is used to read the state of the current coil register.
When the output state is invalid, the indicator light goes out and returns to 0; when valid, the indicator light comes on and returns to 1;
Write a request packet format specification for a single discrete output
Write a single coil request
Serial number | Message Field | Length (bytes) | Bytes, storage mode | I1nstruction |
1 | Transaction identification | 2 | High Byte first | It’s usually a message serial number |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x05 | The related function code of the Modbus communication protocol |
6 | Write address | 2 | High Byte first | |
7 | Write value | 2 | High Byte first | Write 0XFF00 to enable output; write 0X0000 to stop output; |
Write a format description of the reply message for a single discrete output
Write coil response
Serial number | Message Field | Length (bytes) | Bytes, storage mode | I1nstruction |
1 | Transaction identification | 2 | High Byte first | Usually, a message serial number is the same as the request message |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x05 | The related function code of the Modbus communication protocol |
6 | Write address | 2 | High Byte first | |
7 | Write value | 2 | High Byte first | Write 0XFF00 to enable output; write 0X0000 to stop output; |
Example message description Close the output of Channel 1 Request message: 31 A6 00 00 00 06 01 05 00 00 00 00 Reply message 31 A6 00 00 00 06 01 05 00 00 00 00 Enable the output of Channel 1 Request message: 31 A6 00 00 00 06 01 05 00 00 FF 00 Reply message 31 A6 00 00 00 06 01 05 00 00 FF 00
(4) Digital output signal multiple control commands
Protocol statement
Function code: 0x0F
Discrete output register 0x00-0x15 corresponds to output channel 1-16; this instruction is used to read the state of the current coil register.
When the output state is invalid, the indicator light goes out and returns to 0; when valid, the indicator light comes on and returns to 1;
Write a request packet format specification for multiple discrete outputs
Write multiple coil requests
Serial number | Message Field | Length (bytes) | Bytes, storage mode | Instruction |
1 | Transaction identification | 2 | High Byte first | It’s usually a message serial number |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x0F | The related function code of the Modbus communication protocol |
6 | Starting address | 2 | High Byte first | |
7 | Write length | 2 | High Byte first | |
8 | Number of bytes of data written | 1 | Writes a data length of N bytes, then writes a data byte value of n | |
9 | Write data | N | Low byte in front, high bit per byte, in front | Each byte corresponds to 8 bits of discrete output |
Write format specifications for multiple discrete output reply packets
Write multiple coil responses
Serial number | Message Field | Length (bytes) | Bytes, storage mode | I1nstruction |
1 | Transaction identification | 2 | High Byte first | It’s usually a message serial number |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x0F | The related function code of the Modbus communication protocol |
6 | Starting address | 2 | High Byte first | |
7 | Write value | 2 | High Byte first |
Example message description
1 ~ 16 channel output enable
Request message:
31 A6 00 00 00 09 01 0F 00 00 00 10 02 FF FF
Reply message
31 A6 00 00 00 06 01 0F 00 00 00 10
3 ~ 10 channel output enable
Request message:
31 A6 00 00 00 08 01 0F 00 02 00 08 01 FF
Reply message
31 A6 00 00 00 06 01 0F 00 02 00 08
(5) Input Register Acquisition Command
Protocol statement
Function code: 0x04
Input Register 0x00-0x05 corresponds to analog input channels 1-6
When the input port state is invalid, the indicator light goes out and returns to 0; when valid, the indicator light turns on and returns to 1;
Read Input Register request message format description
Read discrete INPUT REQUEST -MODBUS TCP packet format)
Serial number | Message Field | Length (bytes) | Bytes, storage mode | I1nstruction |
1 | Transaction identification | 2 | High Byte first | It’s usually a message serial number |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x04 | The related function code of the Modbus communication protocol |
6 | Starting address | 2 | High Byte first | |
7 | Number of registers | 2 | High Byte first |
Format description of read input register reply message
Read the discrete input reply (Modbus TCP message format)
Serial number | Message Field | Length (bytes) | Bytes, storage mode | I1nstruction |
1 | Transaction identification | 2 | High Byte first | Usually, a message serial number is the same as the request message |
2 | Protocol identification | 2 | High Byte first | The default is 0000 |
3 | Message length | 2 | High Byte first | The data length, excluding transaction identification, protocol identification, and message length |
4 | Unit identification | 1 | Range from 0x00 ~ 0xff; local bit 0 or 1; rest for RS485 ports; from machine address | |
5 | Function code | 1 | 0x04 | The related function code of the Modbus communication protocol |
6 | Data Length | 1 | High Byte first | N analog channels, data length value of 2n |
7 | Data | 2n | Analog current input in the front, the low word in front |
Example message description For example, the analog voltage input is 10V, the analog current input is 20ma, and the analog current input is 6 channels Request message: 00 04 00 00 00 06 01 04 00 00 00 06 Reply message 00 04 00 00 00 0F 01 04 0C 05 12 05 15 05 15 0F 80 0F 82 0F 88
5.2 Modbus RTU to MODBUT TCP Communication Mode
The module can transform the Modbus RTU message of 485 ports into a TCP message, and realize data conversion between Modbus RTU main station and the MDOBUC TCP server. Here’s how it works:

5.2.1. Modbus RTU to Modbus TCP communication mode parameters
Parameter type | Detail |
Default remote host IP | 192.168.1.124 |
Default remote host port | 8080 |
Number of supported connections | 1 |
Native TCP Mode | Client |
RS485 communication parameter | ➢ Line 2: A to the 485 bus B-minus on 485 bus ➢ Default communication parameters: Baud rate: 9600,8-bit data, no parity, 1-bit stop, web configurable |
5.2.2 Modbus RTU to Modbus TCP mode configuration
Step 1: Open the web page and go to the “Parameter configuration” screen. See section 5.3, “Page configuration parameters” for details
Step 2: select the 485 parameters as” Client”, as shown in the following figure

Step 3: Configure the IP and Port of the Modbus TCP server on demand, as shown in the following figure

Step 4: Configure Module RS485 serial port parameters according to requirement, refer to section 5.3.2 for detailed operation
Step 5: Power Off and Restart the module
5.3 Page configuration parameters
Here’s how it works:
- Connect the module (through the switch) to the computer using a common network cable.
- Connect the external power supply of DC 24V to the module and electrify it. Before electrifying, please check whether the positive and negative poles of the power supply are connected correctly.
- Open the browser with Google, Firefox, or Ie9 + and enter the current IP of the module (the default IP for the module is 192.168.1.15).
- Enter the login password, the default password is 123456; the password can be changed through the web page.
5.3.1 Web Login
Enter your password and click the “Log in” button to log in

Upon successful landing, the following is displayed:

5.3.2. Configure serial port parameters
Including the configuration of 485,232,422 port communication parameters, baud rate, stop bit and check bit.
Select the”[3] parameter configuration” button to enter, as shown in the following figure:

Take the configuration of 485 port communication parameters as an example
As shown below, configure the baud rate, check bit, stop bit, and communication mode in “485 parameters” under “Serial parameters”.

5.3.3 configure module IP
As shown in the following figure, under parameter configuration, configure the IP, Gateway, and subnet mask in the local network parameters.

5.3.4 Set a login password
As shown in the figure below, under “Parameter configuration”, under “Login password”, just enter 6 digits.

5.4.5. Factory settings are restored
As shown in the figure below, first select “Functional configuration”.

In the pop-up page, select “Restore factory settings” and power off to restart, as follows:

5.4 TCP to RS232 transmission
This module supports converting any received message of 232 ports into a TCP message and sending it; the TCP client receives the same message as the module 232 ports.
5.4.1 TCP to RS232 communication parameter description
Parameter type | Detail |
Default module IP | 192.168.1.15 |
Default Module Port | 9232(unmodifiable) |
Native TCP Mode | This machine acts as the TCP server |
RS232 communication parameter | Line 3: 2-RXD, 3- TXD, 5- ground Default communication parameters: Baud rate: 9600,8-bit data, no check, 1-bit stop. |
Explanation:
RS232 port communication parameters, baud rate, check bit, and stop bit can be set through the web page.
5.4.2 TCP to RS232 communication settings
Step 1: Open the web page and go to the “Parameter configuration” screen. See section 5.3, “Page configuration parameters” for details
Step 2: set the required RS232 serial port parameters as shown in the following figure

Step 3: set up the module IP on Demand, refer to section 5.3.3 for detailed operations
Step 4: Power Off and restart the module
5.5 TCP to RS422 transmission
This module supports the conversion of any received message of port 422 into a TCP message and sending it; the TCP client receives the same message as the module 422
5.5.1 TCP to RS422 default communication parameter description
Parameter type | Detail |
Default module IP | 192.168.1.15 |
Default Module Port | 9422(unmodifiable) |
Native TCP Mode | This machine acts as the TCP server |
RS422 communication parameter | Line 4: Module send: t + , T – Module receive: R + , R – Default communication parameters: Baud rate: 9600,8-bit data, no check, 1-bit stop. |
Explanation:
RS422 port communication parameters, baud rate, check bit, and stop bit can be set through the web page.
5.5.2 RS422 communication parameter setting
Step 1: Open the web page and go to the “Parameter configuration” screen. See section 5.3, “Page configuration parameters” for details
Step 2: set the required RS422 serial port parameters as shown in the following figure

Step 3: set up the module IP on Demand, refer to section 5.3.3 for detailed operations
Step 4: Power Off and restart the module
5.6 TCP to RS485 transmission
This module can convert any received message of port 485 to a TCP message and send it. The TCP client receives the same message as that of Port 485
5.6.1, TCP to RS485 communication parameter description
Parameter type | Detail |
Default module IP | 192.168.1.15 |
Default Module Port | 502(unmodifiable) |
Native TCP Mode | Server penetration |
RS485 communication parameter | Line 2: A to the 485 bus B-minus on 485 bus Default communication parameters: Baud rate: 9600,8-bit data, no check, 1-bit stop. |
Explanation:
RS485 port communication parameters, baud rate, check bit, and stop bit can be set through the web page.
5.6.2 TCP to RS485 configuration
Step 1: Open the web page and go to the “Parameter configuration” screen. See section 5.3, “Page configuration parameters” for details
Step 2: Select parameter 485 for “Server penetration”

Step 3:485 serial port parameters and IP modification, detailed Operation Reference Section 5.3.2 and 5.3.3
Step 4: Power Off and restart the module
6. common problems
6.1. The power light doesn’t work
- Check the power supply, whether the reverse connection, whether the DC power supply, voltage is at least 9v;
- If the power is normal, the module may be damaged, please contact us to send it back for repair.
6.2. The device is not communicating
- Whether through the module IP page to choose the correct 485 TCP communication mode and power off restart;
- Through the module IP page to see whether the module’s serial port parameters, network parameters, and equipment matching;
- Whether power off and restart after modifying module parameters
- Use section 4.1.3 to determine if the cable is available.
6.3. Unable to access module IP pages
- Section 4.1.3 to determine if the network cable is usable;
- Check if the login IP is the current module IP;
- Attempts to change browsers such as Google, Firefox, or IE9;
- The computer IP network segment is consistent with the module, whether the module IP and Computer IP conflict, whether the switch/router configuration is the correct IP to the computer, module, etc.
6.4. The page modification parameter did not succeed
- Click OK after the corresponding parameter;
- Power-off restart module modified parameters can be effective, whether there is a power-off restart;