Waveshare UART TO ETH User manual

RS485 TO ETH ( B)
UART TO ETH (B)
User Manual
Figure 1 UART TO ETH (B)
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RS485 TO ETH ( B)
1 . OVERVIEW
It is a UART to Ethernet module designed for industrial environments, small in size, easy to
embed and integrate, with device data collector/IoT gateway, serial server, Modbus gateway, MQTT
gateway, UART to JSON, and many other functions in one. It has a UART interface and an Ethernet
interface.You can directly integrate it into the device application of your own UART/RS232/RS485
port
When used as a common serial port server, connect the UART TO ETH (B) network port to
the Ethernet, and the host computer software can use TCP/ UDP transparent transmission or
virtual serial port mode to send data to UART TO ETH (B) On the UART interface; the data
received on the UART interface will also be transmitted to the software or virtual serial port on
the TCP side. In the virtual serial port mode, the serial port software connected to the virtual
serial port can be used without any need.
When used as a Modbus gateway, UART TO ETH (B) supports Modbus TCP to Modbus RTU,
so that the host computer uses Modbus TCP protocol to collect data from UART/RS485
Modbus RTU devices. On the contrary, if the UART/RS485 terminal is used as the master
station, it can also be used. The supported multi-master function allows multiple computer
masters to access an RS485 slave device at the same time. In this application scenario, you need
to add some TTL to RS485 circuits, or use our ready-made RS485 to network port modules, such as
RS485 TO ETH (B), RS485 TO POE ETH (B),etc.
When used as an MQTT gateway, the device can transparently upload serial port data to the
MQTT server using the MQTT protocol. Supported servers include Baidu Cloud MQTT, Alibaba
Cloud MQTT, China Mobile OneNet platform, etc. Support to parse the collected Modbus RTU or
non- standard serial port data into JSON format, encapsulate it in MQTT data package and upload
it. Support JSON format to upload collected data, automatic data collection, collected data
support Modbus RTU, 645 meter 97 version, 645 meter 07 version, various non-standard RS485
protocols. Users can configure the uploaded data format and JSON keywords with Vircom. When
uploading, it can support MQTT protocol, HTTP POST protocol, HTTP GET protocol, transparent
transmission protocol, and various non-standard network protocols. RS485 TO ETH (B) has
various functions of a powerful IoT gateway, which is very suitable for collecting various RS48 5
instruments and sensors in the industrial field, including local network collection or uploading to
the cloud server.
UART/RS485 TO ETH (B) can be applied to ：
As a gateway of the Internet of Things as a communication bridge between the device and
the cloud;
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Electricity, smart meters and energy consumption monitoring;
Remote monitoring and program downloading of various automated PLCs;
Various configuration software and equipment communication interfaces;
Equipment networking in the field of access control and security;
A typical application connection is shown in Figure 2. The original serial device UART is
connected to the UART port of RS485 TO ETH (B), and UART TO ETH (B) is connected to the
computer through a network cable. The software on the computer establishes a connection with
UART TO ETH (B) through TCP/ IP or virtual serial port. After that, any data sent by the serial
device will be transparently transmitted to the computer software, and the data sent by the
software via the network UART TO ETH (B) will also be transparently transmitted to the serial
device
Figure 2 Connection diagram
2 . FEATURES
2 . 1 . HARDWARE FEATURES
Compact And Easy Integration
Castellated Holes With Immersion Gold Design, Highly Integrated Packaging
Supports Multiple Ways To Be Embedded Into Various Product Applications

RS485 TO ETH ( B)
2 . 2 . SOFTWARE FEATURES
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Support TCP server, TCP client, UDP mode, UDP multicast. As a TCP client, it also supports
TCP server functions. As a TCP server, it supports 30 TCP connections, and as a TCP client, it
supports 7 destination IPs.
The baud rate supports 1200—115200bps, the data bit supports 5-9 digits, and the parity
bit can be five modes: no parity, odd parity, even parity, mark, and space.
It supports the function of sending MAC address on the device connection, which is
convenient for cloud management of the device.
Provide the secondary development kit DLL development library for searching and
configuring equipment on the computer side.
Support Web browser configuration, DHCP dynamic acquisition of IP, DNS protocol to
connect to the domain name server address.
Support cloud remote search for devices, configuration of device parameters, and device
program upgrades.
Support remote viewing of the device's TCP connection status, serial port data sending and
receiving status through software. Virtual serial port supports data monitoring function.
2 . 3 . ADVANCED SOFTWARE FEATURES
Support Modbus gateway function, support Modbus RTU to Modbus TCP. It can support
storage Modbus, which can automatically collect device data and store it; it also supports
non- storage mode Modbus gateways
Support multi-host function: In the query mode of one question and one answer, the
support network port allows multiple computers to access the same serial device at the
same time.
Support MQTT gateway function.
Support JSON to Modbus RTU and 645 instrument protocol, support HTTP POST, HTTP GET
format to upload data.
Support NTP protocol to obtain network time, which is used for serial port output and the
latter is used for protocol content uploading.
Support custom heartbeat package and registration package function: it can facilitate
communication and device identification with the cloud.
Support the function of password authentication required for TCP connection establishment
to ensure connection security.
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RS485 TO ETH ( B)
Supports the http method of data submission and distribution. The cloud can directly use
the http GET command to interact with the device's serial port data.
3 . TECHNICAL PARAMETER
Table 1 Technical parameters
Appearance
Communication interface
UART
Power supply
3.3V/5V, pin header or pad
Dimensions
L x W x H =3.4cm×2.3cm×1.15cm
Communication interface
Ethernet
RJ45 interface
Serial port
RXD ，TXD，GND
Serial port parameters
Baud rate
300~115200bps
Check Digit
None, Odd, Even, Mark, Space
Data bits
5~9 bits
Flow control
optional
software
Protocol
ETHERNET、IP、TCP、UDP、HTTP 、ARP 、ICMP 、DHCP、
DNS
Configuration method
VirCOM tool, WEB browser, device management function
library
Communication mode
TCP/ IP direct communication, virtual serial port mode
Operating mode
TCP server, TCP client (TCP server coexists at the same time), UDP, UDP multicast
Power requirements
Power
3.3V/5V
Environmental requirements
Operating temperature
-40~85C
Humidity range
5~95% relative humidity
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d
CONTENT
目录
Figure 2 Connection diagram ....................................................................................................................... 3
2 . 1 . HARDWARE FEATURES.......................................................................................................... 3
2 . 2 . SOFTWARE FEATURES ........................................................................................................... 4
Table 1 Technical parameters ......................................................................................................................6
4 . 1 . HARDWARE DESCRIPTION ................................................................................................... 9
Figure 3 Front view...................................................................................................................................... 9
Figure 4 Power supply, network port........................................................................................................ 10
Figure 5 The back of the device................................................................................. 错误！未定义书签。
4 . 2 . HARDWARE CONNECTION.................................................................................................13
4 . 3 . SOFTWARE INSTALLATION ................................................................................................ 13
Table 3 Software description..................................................................................................................... 13
Figure 7 Device list..................................................................................................................................... 14
Figure 8 Device parameters ....................................................................................................................... 15
Table 4 Parameter meaning.......................................................................................................................15
Add virtual serial port................................................................................................................................ 21
Enable Modbus TCP function..................................................................................................................... 24
Modbus TCP as client................................................................................................................................. 24
Web login interface ....................................................................................................................................25
Web configuration interface ......................................................................................................................26
5 . 2 . DIRECT TCP/ IP COMMUNICATION MODE
..........................................................................................................................................................28
5 . 2 . 1 . TCP CLIENT MODE .................................................................................................................. 28
5 . 2 . 2 . CLIENT CONNECTS TO MULTIPLE SERVERS................................................... 29
5 . 2 . 3 . TCP SERVER MODE ................................................................................................ 31
5 . 2 . 4 . ACTING AS BOTH A CLIENT AND A SERVER...................................................31
5 . 2 . 5 . UDP MODE................................................................................................................................ 32
6 . 1 . NETWORK PHYSICAL CONNECTION................................................................................ 35
6 . 2 . NETWORK TCP CONNECTION........................................................................................... 35
6 . 3 . DATA SENDING AND RECEIVING..................................................................................... 36
6 . 4 . VIRCOM REMOTE MONITORING DATA......................................................................... 36
7 . MODBUS ADVANCED FUNCTIONS ............................................................................................ 38
7 . 1 . ENABLE MODBUS GATEWAY ............................................................................................ 38
7 . 4 . MULTI - HOST FUNCTION .....................................................................................................41
7 . 6 . MODBUS UNDER MULTI - DESTINATION IP................................................................... 44
8 . REGISTRATION PACKAGE AND HEARTBEAT PACKAGE ....................................................... 44
8 . 1 . 1 . SEND MAC ADDRESS ON CONNECTION.......................................................... 45
8 . 1 . 2 . REALCOM AGREEMENT.........................................................................................................45
8 . 1 . 3 . CUSTOM REGISTRATION PACKAGE.................................................................. 46
8 . 1 . 4 . CONFIGURATION FILE ........................................................................................................... 47
8 . 2 . HEARTBEAT PACKAGE .........................................................................................................48
8 . 2 . 1 . IMPLIED HEARTBEAT............................................................................................................. 48
8 . 2 . 2 . REALCOM PROTOCOL........................................................................................... 49
8 . 2 . 3 . CUSTOM HEARTBEAT PACKAGE ........................................................................ 49
9 . REMOTE DEVICE MANAGEMENT.............................................................................................. 49

RS485 TO ETH ( B)
7.4. Multi-host function............................................................................................................39
7.5. Multi-host parameters.......................................................................................................40
7.6. Modbus under multi-destination IP.................................................................................42
8 . Registration package and heartbeat package...................................................................... 4 2
8.1. Registration package.........................................................................................................4 3
8.1.1. Send MAC address on connection....................................................................... 4 3
8.1.2. Realcom Agreement.............................................................................................. 43
8. 1.3 . Custom registration package................................................................................4 4
8.1.4. Configuration file................................................................................................... 45
8.2. Heartbeat package.............................................................................................................46
8.2.1. Implied heartbeat.................................................................................................. 46
8.2.2. REALCOM protocol................................................................................................ 47
8.2.3. Custom heartbeat package...................................................................................47
9 . Remote device management................................................................................................. 4 7
10. MQTT and JSON..................................................................................................................... 49
11 . firmware upgrade method................................................................................................... 4 9
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RS485 TO ETH ( B)
4 . INSTRUCTIONS FOR USE
The UART TO ETH (B) module is used to realize the two-way transparent transmission of
data from the serial port to the Ethernet port. The user does not need to care about the specific
details, and the module completes the protocol conversion inside. The serial port side is the
serial port level data, and the Ethernet port side is the network data packet. You can specify the
work details through simple settings. The parameters can be set through the built-in webpage or
through the setting software, and the settings can be saved forever.
This chapter is the user manual for the product UART TO ETH (B). It is recommended that
users read this chapter systematically and follow the instructions to get a systemic
understanding of this product. Users can also choose the chapters they are interested in to read
according to their needs. For specific details and instructions, please refer to the subsequent
chapters.
In addition to this manual, we also provide configuration software and other materials
based on this product for user design reference download link :
http://www.waveshare.com/wiki/UART_TO_ETH_( B)_
4 . 1 . HARDWARE DESCRIPTION
Figure 3 Front view
The front view of the U A R T TO ETH ( B) serial server is shown in the figure above.
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RS485 TO ETH ( B)
Figure 4 UART TO ETH (B)
UART TO ETH (B) Pinout
Pin
Model
Description
5V
Power
5V Power Input
3.3V
Power
3.3V Power Input
GND
Ground
Ground
RST
Reset
Reset pin, low active. It is recommended to use
max811reus or a similar reset chip. Noise can be
filtered by a 0.1u capacitor. Low-level minimum time
100ns.
TXD
OUT
Serial data transmitting pin of the module, 3.3V TTL
level, can be connected to RXD of user MCU.
RXD
IN
Serial data receiving pin of the module, 3.3V TTL level,
can be connected to the user MCU's TXD.
DEF
IN
When the parameter is reset to 0 and held for more

RS485 TO ETH ( B)
than 1 second, the module will restart with the default
IP of 192.168.1.254, static IP mode, 255.255.255.0
gateway, and 192.168.1.1 gateway. You can also set
your own reset parameters with the param.txt
configuration file.
RUN
OUT
Working indicator, the chip works properly, and will
output a square wave with a period of 2 seconds. You
can connect a 4.7K resistor and then connect the LED
to the ground and the LED is on indicating the chip
has been working.
EN
OUT
The 485 transmit controller, normally 0, becomes 1
when the module sends data to the serial port. It can
be connected directly to the TXD_EN pin of the
MAX485 chip.
RTS
OUT
Hardware flow control output. After the flow control is
set to CTS/RTS, DTR/DSR, RTS=0 normally, if RTS=1, it
means the module can't receive data and the user
MCU should stop sending data to the module.
CTS
IN
Hardware flow control input, when the chip is
configured for CTS/RTS, DSR/DTR serial mode, only
when CTS=0, the chip serial port will output data to
the outside.
GND
Ground
Ground
LINK2
OUT
When it is 0, it indicates that the module RJ45 network
cable is connected.
ACT
OUT
Data indicator. When it is 0, it indicates that there is
data being sent and received at the serial port. But
when there is data, this pin will jump between 0 and 1.
ACT=1, which cannot be used as a flag for no data
communication.
LINK
OUT
TCP connection indicator. When it is 0, the module has
established TCP/UDP connection with the network
server, and the module can send and receive data
normally. If the network cable is unplugged at this

RS485 TO ETH ( B)
time, the LINK will change to 1.
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RS485 TO ETH ( B)
4 . 2 . HARDWARE CONNECTION
Generally speaking, the serial server only needs to be connected to the power supply, serial
port, and network cable.
The network port is connected to a common network cable, which can be directly connected
to a computer or connected to the network through a switch.
4 . 3 . SOFTWARE INSTALLATION
Vircom can be used to configure parameters such as device IP and create virtual serial ports.
If you do not need the virtual serial port function, you can only download the
installation- free version of the configuration software.
Table 3 Software description
name of software
illustrate
VirCom
Chinese version configuration software
VirCom_ en
English version configuration software
Virtual- serial- port
Virtual serial port software
4 . 4 . PARAMETER CONFIGURATION
After Vircom is installed and the device hardware is connected, run the software as shown
in the figure, and then click "Device Management" as shown in the figure. Using Vircom, you can
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RS485 TO ETH ( B)
search and configure device parameters in different network segments, which is very convenient,
as long as the device and the computer running Vircom are under the same switch.
Figure 6 Vircom main interface
Figure 7 Device list
See all currently online devices from the device list. Click "Edit Device" to configure the
parameters.
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RS485 TO ETH ( B)
Figure 8 Device parameters
In this interface, the user can set the parameters of the device, and then click "Modify
Setting" , the parameters will be set to the flash of the device, and they will not be lost after
power failure. At the same time, the device will automatically restart.
The main configuration parameters here are: baud rate, data bit, parity bit in serial port
settings; IP address, subnet mask, gateway in network settings; sometimes according to
computer software, you also need to configure the work of the serial server model.
The detailed meanings of other parameters are as follows:
Table 4 Parameter meaning
parameter name
Ranges
meaning
Virtual serial
port Unused, created
virtual serial port
You can bind the current device with a created
virtual serial port. Please add a COM port in the
"Serial Port Management" on the main interface
first.
Device model
Only display the model of the core module
Device name
Any
You can give the device an easy-to-read name, up
to 9 characters long
Device ID
Factory unique ID, cannot be modified.
Firmware
version
The firmware version of the core module
Supported
Refer to Table 5 Supported functions of the
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RS485 TO ETH ( B)
functions
device
IP mode
static, DHCP
users can choose static or DHCP (dynamically
obtain IP)
IP address
The IP address of the serial server
Port
0~65535
The listening port when the serial port server is in
TCP Server or UDP mode. As a client, it is best to
specify the port as port 0, which helps to increase
the connection speed. When port 0 is used, the
system will randomly allocate a local port. The
difference between this and non-zero port is: (1)
When the local port is 0, a new TCP connection
will be established with the PC when the module
restarts, the old TCP connection may not be
closed, and the device may have multiple fakes.
connect. Generally, the host computer hopes to
close the old connection when the module
restarts; specifying a non-zero port will close the
old connection. (2) When the local port is 0, the
time for TCP to re-establish the connection is
faster. When the serial port server is in TCP client
mode, it also acts as a TCP server to monitor
connections on the port. At the same time, the
local port number used by the TCP client to
connect to the server is "port+1" .
Working mode
TCP server mode,
TCP client mode,
UDP mode, UDP
multicast
When set to TCP server, the serial port server
waits for the computer to connect; when set to
TCP client, the serial port server actively initiates a
connection to the network server specified by the
destination IP.
Subnet mask
For example:
255.255.255.0
must be the same as the subnet mask of the local
LAN.
Gateway
For example:
192.168.1.1
must be the same as the local LAN gateway.
Destination IP or
domain name
In TCP client or UDP mode, data will be sent to
the computer indicated by the destination IP or
domain name.
Destination port
In TCP client or UDP mode, data will be sent to
the destination port of the destination IP.
Baud rate
300 、600 、1200 、2400、
4800、7200 、9600、
14400 、19200 、28800、
38400 、57600 、76800、
115200、230400、460800
Serial port baud rate
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RS485 TO ETH ( B)
Data bits
5、6、7、8、9
Check Digit
None, Even, Odd, Mark,
Space
Stop bit
1、2
Flow control
No flow control,
Hard flow control
CTS/ RTS, hard flow
control DTR/ DCR, soft
flow control XON/ XOFF
only valid for RS232 serial port
DNS server
When the destination IP is described by a domain
name, this DNS server needs to be filled in.
Server IP. When the IP mode is DHCP, there is no
need to specify DNS
Server, it will be automatically obtained from the
DHCP server.
Destination
mode
In static and dynamic
TCP client mode: After using the static destination
mode, the device will automatically restart the
device after 5 consecutive failures to connect to
the server.
Conversion
agreement
NONE 、
Modbus TCP<-> RTU、
Real_COM
NONE means that the data forwarding from the
serial port to the network is transparent;
Modbus TCP<-> RTU will directly convert Modbus
TCP protocol to RTU protocol, which is convenient
to cooperate with Modbus TCP protocol; RealCOM
is designed to be compatible with the old version
of REAL_COM protocol. It is a protocol of virtual
serial port mode, but it uses virtual serial port. At
this time, it is not necessary to choose the
RealCom protocol.
Keep-alive
timing time
0~255
Heartbeat interval. (1) When the selection is
1~255, if the device is in the TCP client working
mode, it will automatically send TCP heartbeats
every "Keep Alive Time". This can ensure the TCP
validity of the link. When set to 0, there will be no
TCP heartbeat. (2) When it is set to 0~254, when
the conversion protocol is selected as REAL_COM,
the device will send a data with a length of 1 and a
content of 0 every keep-alive timing time, which
realizes the heartbeat mechanism in the Realcom
protocol. When set to 255, there will be no
realcom heartbeat. (3) When it is set to 0~254, if
the device works as a TCP client, the device will
send device parameters to the destination
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RS485 TO ETH ( B)
computer every keep-alive time. When it is set to
255, there will be no parameter sending function,
which can realize remote device management.
Disconnection
reconnection
time
0~255
0~255 When in TCP client mode, when the
connection is not successful, each "disconnection
reconnection time" will re- initiate TCP connection
to the computer. It can be 0~254 seconds. If you
set 255, it means that you will never reconnect.
Note that the first TCP connection (such as
hardware power- on, device restart via Vircom
software, no data light) will generally be carried
out immediately, and only after the first
connection fails will it wait for the "disconnected
reconnection time" and try again, so
" Disconnected reconnection time" will not affect
the connection establishment time of the network
and the server under normal conditions.
Web access port
1~65535
The default is 80
Adress of
multicast
Used in UDP multicast
Enabling the
registration
package
When the TCP connection is established, the
registration package is sent to the computer. After
enabling the registration package, the realcom
protocol must be selected. Support TCP server and
TCP client mode.
Data packet
length
1~1400
1~1400 One of the serial framing rules. After the
serial port server serial port receives the length of
data, it sends the received data to the network as
a frame.
Data packet
interval
0~255
The functions supported by the device are explained as follows:
Table 5 Functions supported by the device
Name
Description
Domain Name
System
The destination IP can be a domain name (such as the www server
address at the beginning).
REAL_ COM Protocol
A non-transparent serial port server protocol, suitable for multiple
serial port servers to bind virtual serial ports through the Internet.
Because the MAC address of the device is contained in the protocol, it
is helpful for the host computer to identify the device. Under normal
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circumstances, it can not be used.
Modbus TCP to RTU
can be converted from Modbus TCP to RTU . It also supports
multi- host function.
Serial port
modification
parameters
Support serial port AT commands to configure and read device
parameters.
Obtain IP
automatically
support DHCP client protocol
Storage expansion EX
function
Subsequent expansion
Multiple TCP
connections
When acting as a TCP server, it supports more than 1 TCP connection.
IO port control
Supports any custom commands to control 8 IO outputs.
UDP multicast
UDP multicast
Multi- destination IP
As a TCP client, it supports simultaneous connection to 7 destination
IPs.
4 . 5 . TCP COMMUNICATION TEST
After configuring the device parameters, you can use the serial port tool and TCP debugging
tool to test the TCP connection communication.
Figure 9 Schematic diagram of TCP communication
The serial port server's serial port to network port, network port to serial port data
transparent forwarding function.
Assuming that the COM port (USB TO TTL) of the PC is connected to the serial port of the
serial server, then open the serial debugging assistant window and open the corresponding COM
port, as shown in the figure below:
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RS485 TO ETH ( B)
Figure 10 SSCOM1: USB TO TTL transceiver interface
In addition, open one more serial port debugging assistant window and use it as a TCP client
mode. Fill in the destination IP as the IP of the serial server (currently 192.168.1.200) and the
destination port as 4196, and then click the "Open" button, as shown in the figure below:
Figure 11 SSCOM2: TCP Client transceiver interface
Enter "TCPClient : Waveshare Test" in the serial debugging assistant SSCOM2 set as
TCPClient and click send, then the data will be transferred to the RS485 interface through the
serial server's network port, and then sent to the USB TO RS485, and then displayed in the serial
debugging assistant SSCOM1 Come out; conversely, input "USB TO TTL: Waveshare Test" in
SSCOM1, and click Send to send to SSCOM2 and display it.
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