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RS485 TO ETH (B)
User Manual
Figure 1 RS485 TO ETH (B)
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1. OVERVIEW
RS485 TO ETH (B), a RS485 device data collector/IoT gateway, is designed for Industrial
control system. Integrating multiple functions such as serial server, Modbus gateway, MQTT
gateway, RS485 to JSON and so on, it features an RS485 interface and an Ethernet interface. It is
rail-mount, compact and easy to install, and it has terminals for 9~24V power input. As the
RS232 interface is not commonly used in industrial instruments, there is only RS485 interface on
RS485 TO ETH (B), which saves cost and volumes, and is cost-effective compared with other
products.
When used it as a common serial port server, you can connect the network port of RS485
TO ETH (B) to the Ethernet, and the host computer software can send data to RS485 TO ETH (B)
on the RS485 interface by TCP/UDP transparent transmission or the virtual serial port mode; and
the data received on the RS485 interface will also be transmitted to the software or the virtual
serial port on the TCP side. In the virtual serial port mode, the connection can be set up without
the serial software.
When used as a Modbus gateway, RS485 TO ETH (B) supports Modbus TCP to Modbus RTU,
so that the host computer collects data from RS485 Modbus RTU devices with Modbus TCP
protocol.The RS485 terminal also can be used as the master station and its multi-master
function allows multiple host computers to access one of RS485 slave devices at the same time.
When used as an MQTT gateway, the device can transparently upload the serial port data
to the MQTT server with the MQTT protocol. Supported servers include Baidu Cloud MQTT,
Alibaba Cloud MQTT, China Mobile OneNet platform, etc. Also, it can parse the data from the
Modbus RTU or non-standard serial port into JSON format, upload it in MQTT data package.
Support the collected data in JSON format , automatic data collection, and the collected
data supports Modbus RTU, 645 meter 97 version, 645 meter 07 version, and various nonstandard RS485 protocols. Users can configure the uploaded data format and JSON keywords
with Vircom. When uploading, it supports MQTT protocol, HTTP POST protocol, HTTP GET
protocol, transparent transmission protocol, and various non-standard network protocols.
RS485 TO ETH (B) has various IoT gateway functions, which is very suitable for collecting
various RS485 instruments and sensors in the industrial field, including local network collection
or uploading to the cloud server.
RS485 TO ETH (B) can be applied to
As a loT gateway for connecting the device and the cloud;
：
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2. FEATURES
2.1 .HARD WARE FEATURES
2.2 .SOFTW AR E FEATURES
Monitoring electricity, smart meters and energy consumption;
Remote monitoring and program downloading of various automated PLCs;
Various configuration software and equipment communication interfaces;
Provides network for the access control and security;
A typical application connection is shown in Figure 2. The original serial device RS485 is
connected to the RS485 port of RS485 TO ETH (B), and RS485 TO ETH (B) is connected to the
computer through a network cable. The software on the computer establishes a connection with
RS485 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 that is sent by
the software to RS485 TO ETH (B) will also be transparently sent to the serial devices.
Figure 2 Connection diagram
Rail design: suitable for the inside cabinets in the industrial field
Small size: Compared with ordinary serial server, the width is smaller and does not take up space
Terminal type power supply, 9~24V wide voltage input, with reverse power protection
RS485 terminal interface, support 32 slave devices, the baud rate supports 300~115200bps
Abundant panel indicators: In terms of connection, there are not only LINK lights that
indicate whether the network cable is connected, but also LINK lights that indicate the
establishment of a TCP connection; the data indicator includes "serial port to network
port" and "network port to serial port.
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2.3.ADVANCED SOFTWARE FEATURES
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 can send MAC address on the device connection, which is convenient for the cloud management
in the device.
Provide the searching function on the computer, and come with the customized library for
developing DDL.
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.
Support Modbus gateway, Modbus RTU to Modbus TCP. It also support storage Modbus, which
can automatically collect device data and store it; it also supports non-storage mode Modbus
gateways.
Support multi-host: 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.
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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3. TECHNICAL PARAMETER
Appearance
Communication interface
RS485, wiring terminal mode
Power supply
terminal mode
Dimensions
L x W x H =8.7cm×3.6cm×5.9cm
Communication interface
Ethernet
RJ45 interface, 2 KV surge protection
Serial port
RS485×1：RXD，TXD，GND
Serial port parameters
Baud rate
300~115200bps
Check Digit
None, Odd, Even, Mark, Space
Data bits
5~9 bits
Flow control
No flow control
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
9~24V DC
Environmental requirements
Operating temperature
-40~85℃
Storage temperature
-45~165℃
Humidity range
5~95% relative humidity
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.
Table 1 Technical parameters
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CONTENT
1.
Overview
.................................................................................................................................2
2.
Features
2.1.
2.2.
2.3.
3.
technical parameter
4.
Instructions for use
4.1.
4.2.
4.3.
4.4.
4.5.
4.6.
4.7.
4.8.
5.
Working mode and conversion agreement
5.1.
.................................................................................................................................. 3
Hardware features............................................................................................................ 3
Software features..............................................................................................................3
Advanced software features............................................................................................ 4
...............................................................................................................5
................................................................................................................ 8
Hardware description
...................................................................................................... 8
Hardware connection.................................................................................................... 11
Software Installation
..................................................................................................... 11
Parameter configuration............................................................................................... 11
TCP communication test
Virtual serial port test
Modbus TCP test
............................................................................................................21
................................................................................................17
....................................................................................................19
Web configuration......................................................................................................... 23
........................................................................24
Virtual serial port mode................................................................................................ 25
5.2.
Direct TCP/IP communication mode
5.2.1.
TCP client mode.................................................................................................. 26
5.2.2.
Client connects to multiple servers
5.2.3.
TCP server mode.................................................................................................29
5.2.4.
Acting as both a client and a server
5.2.5.
UDP mode........................................................................................................... 30
5.3.
Device couplet way
6.
Equipment debugging..........................................................................................................33
6.1.
Network physical connection
6.2.
Network TCP connection
6.3.
Data sending and receiving
6.4.
Vircom remote monitoring data................................................................................... 34
7.
Modbus advanced functions
7.1.
Enable Modbus gateway............................................................................................... 36
7.2.
Storage Modbus Gateway
7.3.
Disable storage functions
........................................................................................................31
...............................................................................................33
........................................................................................... 34
...............................................................................................36
.............................................................................................37
.............................................................................................. 39
.............................................................................26
................................................................... 27
...................................................................29
........................................................................................33
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7.4.
Multi-host function
........................................................................................................39
7.5.
Multi-host parameters
7.6.
Modbus under multi-destination IP..............................................................................42
8.
Registration package and heartbeat package
8.1.
Registration package
8.1.1.
Send MAC address on connection
8.1.2.
Realcom Agreement
8.1.3.
Custom registration package
8.1.4.
Configuration file................................................................................................ 45
8.2.
Heartbeat package
8.2.1.
Implied heartbeat
8.2.2.
REALCOM protocol
8.2.3.
Custom heartbeat package
9.
Remote device management............................................................................................. 47
10.
MQTT and JSON.................................................................................................................49
11.
Firmware upgrade method
.................................................................................................. 40
....................................................................42
..................................................................................................... 43
..................................................................... 43
...........................................................................................43
............................................................................. 44
.........................................................................................................46
...............................................................................................46
............................................................................................. 47
................................................................................ 47
...............................................................................................49
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4.1. HARDWARE DESCRIPTION
4. INSTRUCTIONS FOR USE
The RS485 TO ETH (B) module is used to the 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 data of the
serial port level, and the Ethernet port side is the network data packet. The setting is simple:
with the built-in webpage or the setting software, the parameters can be set and the settings
can be saved forever.
This chapter is about how to use RS485 TO ETH (B). It is recommended that users read this
chapter systematically and follow the instructions to get start. 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/RS485_TO_ETH_(B)_
The front view of the RS485 TO ETH (B) serial server is shown in the figure above, using a
35mm standard rail enclosure.
Figure 3 Front view
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1
Power input: Wiring terminal: 5.08mm terminal. The input voltage is 9~24V.
Figure 4 Power supply, network port
2
RS485: Use RS485 to connect to 485B and 485A. Among them, 485B means 485 negative line,
485A means 485 positive line; 485 can carry 32 sets of load. The longest communication distance
is 1200 meters. Generally, the terminal resistance is only necessary when the RS485 line exceeds
300 meters. The 485 terminal resistance is 120 ohms.
3
Network port: Connect the network cable and support automatic crossover.
4
Indicators: Power (PWR), Link (Link), Active (ACT) lights. Respectively indicate power
supply, connection, and data.
5
Reset: Short-circuit the two NC pins in the above picture for more than 5 seconds, the
module will be reset to the IP as 192.168.1.254, and various downloaded configuration files
will not be loaded.
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Table 2 Indicator light meaning
Indicator light
PWR
Power Indicator
LINK
(1)
Link is green when the network cable is connected.
(2)
When the TCP connection is established (or in UDP mode),
Link is blue (actually with a faint green light). It can be used to
check whether the serial port server has established a
communication link with the host computer software.
ACT
(1)
When the network port sends data to the serial port, the
indicator is green. The flashing time is 1 second longer than
the actual communication time, which makes it easier to find
the communication with short data.
(2)
When the serial port sends data to the network port, the
indicator is blue and green at the same time. Since blue is
brighter, it indicates that there is a serial port returning data to
the network port if you see blue. This can determine whether
the device responds to commands from the host computer. If
there is no response, it indicates that the serial port baud rate is
incorrect or the serial port is not connected properly.
Use indicators to debug communication method:
1)
If the Link light is not green, the network cable is not connected properly, please check the
network cable.
2)
If the Link light is not blue (only consider the TCP working mode), it means that the
host computer software does not establish the connection with the serial server, please
check whether the IP address is in the same network segment.
3)
If the Active light is green, it means that the network port has sent data, but the serial
device has not returned the data. Please check whether the baud rate is configured correctly
or whether the RS485 are connected reversely.
6 Installation method: The shell is equipped with a 35mm standard guide rail. When there is a guide rail,
the equipment can be directly installed with it.
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4.2. HARDWARE CONNECTION
4.3. SOFTWARE INSTALLATION
4.4. PARAMETER CONFIGURATION
Figure 5 The back of the device
name of software
illustrate
VirCom
Chinese version configuration software
VirCom_en
English version configuration software
Virtual-serial-port
Virtual serial port software
Generally speaking, the serial server only needs to be connected to the power supply, the
serialport, and network cable.
The power supply can be a 2-wire power supply on site, which can be directly connected to
the terminals of the power supply.
The serial port needs to be connected according to the user's serial device. Connect 485
positive to 485A and 485 negative to 485B.
The network port is connected to a common networkcable, which can be directly connected
to a computer or connected to the network through a switch.
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.
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
Table 3 Software description
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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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Figure 8 Device parameters
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
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
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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 there are many connections with the
device may be fake. Generally, the host computer
closes the old connection when the module
restarts; specified non-zero port will close the old
connection. (2) When the local port is 0, TCP reestablishes the connection is faster. When the
serial port server is in TCP clientmode, 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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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 entered the 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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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 “reconnection
time" will re-initiate TCP connectionto the
computer. It can be 0~254 seconds. If you set
255, it means that you will never reconnect.
Note that TCP connection for the first time (such
as hardware power-on, device restart via Vircom
software, no data indicator) will generally be
carried out immediately, and only after the first
connection fails will it wait for the "reconnection
time" and try again, so "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:
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
Table 5 Functions supported by the device
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4.5. TCP COMMUNICATION TEST
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.
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 RS485) 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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Figure 10 SSCOM1: USB TO RS485 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 to send, the data will be transferred to the RS485 interface through the
serial server network port, next it will be sent to the USB TO RS485, and finally be displayed in
the serial debugging assistant SSCOM. In turn, input "USB TO RS485: Waveshare Test" in
SSCOM1, and click to send to SSCOM2 and display it.
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4.6. VIRTUAL SERIAL PORT TEST
The SSCOM2 in the figure communicates directly with the serial server via TCP. In order to
allow the serial software that has been developed by the user to communicate with the serial
server, a virtual serial port needs to be added between the user’s program and the serial server.
As shown in the figure, Vircom and the user’s program run on the same computer, and Vircom
virtualizes a COM port, so that this COM port corresponds to the serial server. When the user
program opens the COM communication, it can be sent to the user serial device through the
Vircom serial server. The following demonstrates this operation step:
Figure 12 Application example of virtual serial port
Click "Serial" on the main interface of Vircom, then click "Add", and choose to add COM2,
where COM5 is the COM port that does not exist in the computer.
Add virtual serial port
Then enter the device management, and double-click the device that needs to be bound to
COM2. As shown in the figure, select COM2 in the "Virtual Serial Port" list in the upper left
corner. Then click "Modify Setting", and then click "Restart Dev". And return to the main
interface of Vircom. You can see that COM2 has been connected to the device with IP
192.168.1.200. At this time, COM2 can be used instead of SSCOM2 for communication.
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The virtual serial port has been connected
Open SSCOM to simulate the user's serial port program, open COM2 (the virtual serial port
above), open another SSCOM to simulate a serial device, and open COM3 (hardware serial port).
At this time, the COM2 sending data link is as follows: COM2 —"Vircom —"Serial server network
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4.7. MODBUS TCP TEST
port —"Serial server serial port —"COM3. In turn, COM3 to COM2 can also transmit data:
COM3 —"Serial server serial port —"Serial server network port —"Vircom —" COM2. The
following figure shows the situation of both parties sending and receiving data.
If COM4 is replaced by the user serial port device, COM5 can communicate with the
user device.
Communication via virtual serial port
By default, the data of the serial and network port is transparently transmitted. If you need
to convert Modbus TCP to RTU, you need to select "Modbus_TCP Protocol" as the conversion
protocol in the device setting, as shown in the figure below.
At this time, the device port is automatically changed to 502, the user's Modbus TCP tool is
connected to the 502 port of the serial server's IP, the Modbus TCP commands that have been
sent will be converted into RTU commands and output via the serial port.
For example, if the serial port server receives the Modbus TCP command of 00 00 00 00 00
06 01 03 00 00 0a, the serial port outputs the command of 01 03 00 00 00 0a c5 cd.
Note: The serial port may send multiple commands of 01 03 00 00 00 0a c5 cd. This is
because the default Modbus adopts the storage mode and will automatically train and query
commands in turn. How to switch to non-storage mode will be explained later.
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Enable Modbus TCP function
If the user's Modbus TCP software is used as a slave, you need to change the working mode
to client based on the conversion protocol, and change the destination IP to the IP of the
computer where the Modbus TCP software is located, and the destination port is 502, as shown
in the figure blow.
Modbus TCP as client
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4.8. WEB CONFIGURATION
Using Vircom, you can search and configure device parameters in different network
segments. The Web configuration requires that the computer and serial server are in the same IP
segment, and the IP address of the serial server must be known in advance. But the Web
configuration can be done on any computer without Vircom.
1.
Enter the IP address of the serial port server in the browser, for example http://192.168.1.200,
and open the following web page:
2.
Enter the password in Password: there is no password set by the factory default, and the
password needs to be set through Modify Web Login Key to take effect.
Web login interface
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5. WORKING MODE AND CONVERSION AGREEMENT
Web configuration interface
3.
In the web page that appears, you can modify the serial server parameters. For related
parameters, please refer to Table 4 for the meaning of the parameters.
4.
After modifying the parameters, click the "Submit" button.
Different serial server working modes and conversion protocols can be selected in different
application occasions, so that it can be used more stably and reliably, which will be described in
detail below.
The use of the serial port server is basically divided into two types: with virtual serial port
and non-virtual serial port, as shown in Figure 9 TCP communication diagram and Figure 12 the
function of virtual serial port. The virtual serial mode is for the serial interface (COM) on
the user software, that is, the user software and devices are serial ports. The user
software with the non-virtual serial port mode directly adopt TCP/IP communication, but the user
devices still use the serial port.
In the non-virtual serial port mode, the "conversion protocol" is classified as three modes:
transparent transmission, Modbus TCP to RTU and Realcom protocol. If the user software is
with a fixed Modbus TCP protocol and the lower computer adopts Modbus RTU, you
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5.1. VIRTUAL SERIAL PORT MODE
need to select Modbus TCP to RTU mode. Only w h e n u s i n g t h e multi-serial server as a
NO.
Virtual
serial
port
Device
working
mode
Conversion protocol
Description
1
Use
TCP server
None
Suitable for the user software
opening the COM port to
collect data automatically.
2
Use
TCP client
None
Suitable for the device actively
sends data. If you choose a TCP
server, the device may be failto
reconnect after disconnecting.
3
Do not
use
TCP server
Modbus TCP to RTU
Applicable to the user software is
Modbus TCP, the user device is
Modbus RTU, and Modbus TCP is
the master station.
4
Do not
use
TCP client
Modbus TCP to RTU
Applicable to the user software is
Modbus TCP, the user device is
Modbus RTU, and the Modbus RTU
is the master station.
5
Use
TCP client
Realcom protocol
Multi-serial server as TCP client, and
when using virtual serial port, it is
best to use Realcom protocol.
6
Do not
use
TCP client
None
Applicable to a large number of
devices connected to a cloud, and
in general, the cloud is a public IP
server on the Internet.
7
Do not
use
TCP server
None
Suitable for devices and computers
in the same local network,
monitoring locally, without
cross-Internet communication.
TCP client to connect to one server and the virtual serial port is used on the server, Realcom
protocol can be used.
The usage is summarized as follows:
Table 6 Network configuration mode
If the user software communicates via COM, it must use the virtual serial mode including
PLC software, configuration software, instrument software, etc.
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5.2. DIRECT TCP/IP COMMUNICATION MODE
Check 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 to let the device connect to the server. At this point, 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 or the ① method must be used.
If neither Modbus TCP protocol conversion nor the virtual serial port are required, the user
software may directly communicate with the network port of the serial server by TCP/IP
communication, and the serial server converts TCP/IP data into serial data and sends it to the
serial device.
Generally, the above operation is adopted by the users that develop the upper computer to
communicate by themselves, 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" briefly describes how to communicate when the
serial port server is used as a TCP server. Here we will describe how TCP client, UDP mode, and
multiple TCP connections to 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 terminals that
complies with this protocol can communicate with the serial server. For any 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, only the
client can access the server. If they all are the servers or the clients, the communication is invalid.
When the serial 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.
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(2) IP address correspondence: The destination IP of the serial port server must be the IP
address of the computer where the network tool is located.
(3) Port correspondence: The destination portof the serial server must be the local port of
the network tool. After this setting, the serial server can automatically connect to the network tool,
and data can be sent and received after the connection is established.
Serial server as a client
5.2.2.
CLIENT CONNECTS TO MULTIPLE SERVERS
When the serial server is used as a TCP client, it can connect to 7 destination IP addresses at
the same time, and the data sent by the serial port will be sent to 7 destination IPs too. If there
are not so many servers, leave the rest of the destination IP vacant. The method is as follow：
Figure 14 The first destination IP and port
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Figure 15 The remaining 2~7 IPs and ports
The first IP is set in the device setting interface as shown in Figure 14. The first IP can be a
domain name. For the remaining 2~7 destination IPs, click the "More Advanced Setting..." button
in the device setting interface to open More Advanced Settings for setting.
After all 7 destination IPs are set up, they can be connected automatically. If they are not
connected, they will wait for the "Reconnect Time" time and then reconnect repeatedly.
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5.2.3.
TCP SERVER MODE
When the serial port server is used as the server, there are also three corresponding
relationships, as shown in Figure 16, which will not be explained here. After setting, click the
open button of the network tool to establish a TCP connection with the serial server, and then
you can send and receive data after the connection is established.
Figure 16 Serial port server as TCP server
When the serial port server is used as a server, it can accept 30 TCP connections at the same
time. The data received by the serial port will be forwarded to all established TCP connections. If
you need to realize that data is only sent to the TCP that has recently received network packets,
you need to enable the multi-host function, please refer to 7.4 Multi-host function.
5.2.4.
ACTING AS BOTH A CLIENT AND A SERVER
The serial server can accept TCP connections even when the device is in the TCP client
mode, that is, it also has the TCP server function.
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Figure 17 Acting as both a client and a server
By default, when using Vircom for configuration, if you change the working mode to "TCP
client", the port (that is, the local port) will automatically become 0 (0 means a free port is
randomly selected). In order to support the TCP server mode, the computer software must get
the local port of the device, so a value needs to be specified here.
As shown in Figure 17, the computer software can now connect to the 1024 port of
192.168.1.200 for communication, and the device will also act as a client to connect the 1024
port of 192.168.1.189. It should be noted that since the local port 1024 is occupied by the server,
the local port when used as a client is "port+1", that is, the software on 192.168.1.189 sees that
the incoming port of the device is 1024+1 =1025.
5.2.5.
UDP MODE
In UDP mode, the parameter configuration is shown in Figure 18. The left side is the
configuration for the serial server in Vircom, and the right side is the setting for the serial
debugging tool SSCOM. First of all, both sides must be in UDP working modes. In addition,
indicated by the red arrow, the destination IP and the destination port of the network tool
must point to the local IP and local port of the serial server.
As indicated by the blue arrow, the destination IP of the serial server must be the
computer IP where the network tool is located, and the destination port of the serial server
must be the local port of the network debugging tool. Only after these network parameters
are configured can two-way UDP data communication be ensured.
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5.3. DEVICE C O N N E C T I N G WAY
Figure 18 UDP mode parameter configuration
If the host computer does not adopt the SSCOM program or the virtual serial port, but two
devices are connected through a network port, the configuration method is similar. First, the
user needs to connect two devices and one computer to the same local area network. The
computer runs Vircom, and the purpose of connecting to the computer is only for configuration.
After the configuration is completed, the computer does not need to be connected.
Click on Vircom's device management to find these two devices, as shown in Figure 20.
Then click "Edit Device" to configure the device. Device connections can be divided into TCP and
UDP. If it is TCP connection, the parameters of the two devices are shown in Figure 19. The
parameters shown by the arrows must correspond like the way of connecting with a PC. After
the TCP connection is successful, you can view the connection status by returning to the "Device
Management" dialog box, as shown in Figure 20. If the statuses of the two devices are both
"Connected", it means that the TCP link between the two devices has been established.
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Figure 19 TCP device pairing parameter configuration
Figure 20 TCP device pairing parameter configuration
If it is in UDP mode, the configuration parameters are shown in Figure 21, and the
parameters corresponding to the arrows must be one-to-one. The UDP connection does not
need to check the connection as long as the parameter configuration is correct, the sent data
will be automatically sent to the designated device.
Figure 21 UDP device pairing parameter configuration
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6. EQUIPMENT DEBUGGING
6.1. NETWORK PHYSICAL CONNECTION
6.2. NETWORK TCP CONNECTION
Finally, I need to remind that if the device is connected, in addition to the network port
parameters set according to the above, the correct serial port parameters must also be set.
Mainly, the baud rate of the serial server needs to be consistent with the user device’s. After
setting, the user equipment can send data to each other through the serial ports of the two
serial servers.
The serial server can use a crossover cable or a network cable to connect to the switch or
the computer network port directly.
After the connection is established, the first step is to check whether the Link light is green,
otherwise, please check whether the network cable is connected.
When the device is used as a way to dynamically obtain IP, it cannot be directly connected
to the computer network port. Because there is no DHCP server available (generally a DHCP
server is a router in the LAN). So please specify the IP when connecting directly. At the same time,
the computer also needs to specify a fixed IP.
Configured in the same network segment
Whether it is directly connected or through a switch, when configured as a static IP, the
device and the computer need to be in the same network segment (unless it is cross-gateway
communication), as shown in Figure above.
Since Vircom supports searching and configuration across network segments, the IP address
that can be searched but cannot be communicated is generally not configured correctly. In this
case, you can use Vircom to configure the device in the same network segment.
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6.3. DATA SENDING AND RECEIVING
6.4. VIRCOM REMOTE MONITORING DATA
After configuration, please use 4.5 TCP communication test or 4.6 virtual serial port test,
you can see that the Link light turns blue when the TCP connection is established. The blue link
light can also be seen through Vircom. For example, in the device management list, if the TCP
connection column is "established", it means the link light is blue, as shown in Figure 22. This can
facilitate remote diagnosis.
Figure 22 Connection status and data receiving and sending status
When the Link light turns blue, data can be sent and received between the software and
the serial server. By now, if the software sends a data, the Active light will turn green, and the
duration will generally be at least 1 second. The data will also be output from the serial port of
the serial server, but whether the output data is correct depends on whether the serial port
parameters (including the baud rate, data bit, stop bit and parity bit) are configured. For the
serial device that has send the correct demand. It will respond. Once there is a reply (the serial
port sends data to the network port), the Active indicator will turn blue. Otherwise, please
check the serial port parameters or whether the serial cable is connected.
In order to facilitate remote debugging, Vircom also supports remote viewing of data sent
and received. As shown in Figure 22, TXD is the amount of data sent by the serial port server
serial port. When the device list is refreshed, if this value changes, it indicates that there is data
sent. The Active light will also be green; if you see the value of RXD changing, it indicates that
the serial device has returned data, and Active is blue.
When using the virtual serial port, Vircom supports real-time capture of the data of the
virtual serial port. It is convenient for users to debug the system, and the method is as follows:
It is assumed that the communication of the virtual serial port has been established
according to the method of 4.6 virtual serial port test. Now you need to monitor the data
through the virtual serial port. Open Vircom's menu/Config/software setting/open the Vircom
configuration dialog box.
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Figure 31 Enable Virocm monitoring
Check in front of the three options: open monitoring, hexadecimal monitoring mode, and
display data sending and receiving time, as shown in Figure 23. Then click OK. Assuming that data
has been sent and received before, now select a virtual serial port to be monitored in the main
interface, and then select Menu/View/Monitor, as shown in Figure 24.
Figure 32 Open Virocm monitoring
From the opened dialog box, you can see the instructions issued by the host computer and
the instructions returned by the device, as shown in Figure 25. This function can facilitate on-site
communication debugging.
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7. MODBUS ADVANCED FUNCTIONS
Figure 33 Monitor sending and receiving data
7.1. ENABLE MODBUS GATEWAY
The serial port server with Modbus gateway function does not have station address and
registers. However, it can act as a communication bridge. It will output the specified Modbus RTU
according to the Salve ID, function code, the register number and quantity in Modbus gateway
sent by the user software.
First of all, the serial port server should support Modbus gateway, that is, the "Modbus TCP
to RTU" function in Table 5 Device Supported Functions in the Device Settings dialog box should
be checked.
By default, the serial server is in normal transparent transmission mode. If you need to
switch to Modbus gateway mode, please select the option "Modbus TCP Protocol" in
"Conversion Protocol". After that, the device automatically changes the "port" parameter to 502
(the port of the Modbus server). Then the Modbus gateway is enabled.
If the serial port RTU device is used as a slave station, the host computer Modbus TCP
software connects to port 502 of the Modbus gateway. At this time, the Modbus gateway needs
to work in TCP server mode; if the serial port RTU is used as the master station, the Modbus
gateway works as a TCP client and the destination IP is the IP of the computer where the
Modbus TCP software is located, and the destination port is generally 502.
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7.2. STORAGE MODBUS GATEWAY
This product can save the content of the read register inside the gateway, so that the query
speed of Modbus TCP can be significantly improved, and the performance is even better when it
supports multi-host access.
As shown in Figure 26: The general sending way of the Modbus TCP data is (1) (2) (3) (4).
That is,the Modbus TCP command is converted into the corresponding command of Modbus
RTU at first, the device responds to the Modbus RTU command to the Modbus gateway, and
then the Modbus gateway is converted to Modbus TCP again and sent to the monitoring host
computer.
As Modbus TCP is the network communication, and the transmission speed is very fast.
Generally, it can respond within 3ms, while Modbus RTU adopts RS485, which generally has a
speed of 9600bps. It usually takes at least 30ms to send and return a command. The response
time of such ordinary non-storage Modbus gateways is relatively long. In addition, if there are
a lot of host computers at the same time to query data at the same time, then the serial port
will be congested. If the network is like an expressway, and the serial port is like a single-plank
Figure 26 Working Mode of Storage Modbus Gateway
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bridge, then the original method is to pass the traffic flow of the expressway on the single-plank
bridge.
The register-saving Modbus gateway solves the above problems. It can temporarily save
the register data obtained in the Modbus gateway, so that when the Modbus TCP query, the
Modbus gateway can immediately return the command, which demonstrates Modbus TCP can
be operated quickly. On the other hand, the serial port server can take the initiative to send
instructions from the serial port to automatically update the contents of the currently saved
register data, and save a copy of the latest register value.
In addition, this serial server is a fully automatic configuration-free Modbus gateway,
users do not need to configure the required register address, function code, slave address, etc.
The serial server will automatically recognize and dynamically add these registers according to
the Modbus TCP commands sent from the network port.
RS485 TO ETH (B) can response quickly when monitored by multiple computers. No
matter what baud rate of the serial port is, it can generally response the data to the host
within 3ms, which showed a good updating speed of serial port data.
The register-saving Modbus gateway is a real Modbus TCP to Modbus RTU. It really takes
advantage of the fast speed of Modbus TCP and the ability to query by multiple hosts at the
same time.
Note that when the serial port server is used as a TCP client, it does not have the storage
function and will automatically switch to the non-storage type.
The characteristics of storage Modbus are listed below:
The first Modbus TCP query command is non-storage type. Because you must wait for the
RTU device to return data slowly before returning the register content to the network port.
If a specific command is no longer inquired by the host computer on the network side
within 5 seconds, this command will be automatically deleted and no longer sent to the RTU
device from the serial port.
At present, it can store 10K Modbus cache. For ordinary single-register query, about 500
instructions can be stored at the same time.
When more commands are being queried at the same time, they are sent in order. The
first command sends the first command response and waits for 485 anti-collision time (refer to
the multi-host section). The second command sends... Return to the first command after the
last command has been answered.
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7.4. MULTI-HOST FUNCTION
7.3. DISABLE STORAGE FUNCTIONS
Although the storage Modbus has a faster response speed, some users do not want the
RTU device to receive a large number of query commands, which affects the internal
processing speed of the instrument. The storage function can be turned off at this time.
The method to disable the storage type is to click the "More Advanced Settings" button in
the "Parameter Configuration" dialog box, remove one support and one enable as shown in
Figure 27 and click OK. Then go back to the device settings and click Modify settings.
Note that when using the Web method to configure the conversion protocol, the default
is a non-storage Modbus gateway.
Figure 27 Disable storage function
As shown in Figure 27, "Enable RS485 Multi-Host" and "Enable RS485 bus conflict
detection" are multi-host functions. They are generally enabled and disabled at the same time.
After enabling, let the device whose conversion protocol is Modbus TCP has the storage
Modbus gateway function, otherwise it is a non-storage Modbus gateway; if the conversion
protocol is None, generally the user-defined RS485 protocol can also have serial devices
accessed by multiple hosts at the same time This function cannot be achieved in a pure RS485
network, because multiple master stations sending at the same time will cause conflicts on the
RS485 bus. The multiple hosts of this serial server can "coordinate" the RS485 bus to achieve
the purpose of multi-host access.
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7.5. MULTI-HOST PARAMETERS
Figure 28 Multi-host function demonstration
As shown in Figure 28, in the normal mode, when two hosts: host A and host B
are connected to the serial server at the same time, host A sends (1) command,
RS485 device receives (2) command, RS485 device returns (3) ) command, but the
serial port server will send (4) to host A and (5) to host B at the same time. Since
the host B did not send the query, but it also received the response command (5),
the host B may generate a communication abnormal error. In the multi-host mode,
there will only be command (4) but not command (5), because the serial server will
automatically remember the host that needs to be returned, and only return the
instructions to the most recent communication host, and the query of host A will
only reply to A, host B queries and replies to host B.
Another function is that in the normal mode, when the host A and the host B send data
at the same time, the combination of instructions will be generated on the RS485 bus, so
that it cannot be recognized normally; in the multi-host mode, the serial server can schedule
A and B touse the bus. Prioritize the conflict problem of simultaneous access by multiple
machines in an effective way.
When the conversion protocol is "None", the multi-host function is not enabled by
default.When you need to enable multiple hosts, please click "More Advanced Settings" in
the device configuration dialog box, and then check "RS485 multi-host support".
The meanings of "Enable RS485 Multi-Host" and "Enable RS485 bus conflict detection" are
introduced as follows.
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Figure 37 RS485 multi-host support
The RS485 command response timeout is: the maximum time interval from sending this
command to receiving the response from the serial server serial port.The time to fill in should
be greater than the actual maximum time interval. Because once it is determined to be timed
out, the next command will be sent.
Figure 30 RS485 anti-collision idle time
RS485 bus conflict time: indicates how many milliseconds the serial server waits after
receiving the reply of the first command before sending the second command. This parameter
actually defines the speed of the command rotation. The value is recommended to be more
than 20ms. The parameter "maximum waiting time 3 seconds" generally does not need to be
modified.
When the user uses Vircom to select the conversion protocol as "Modbus_TCP Protocol",
Vricom will automatically check the above two enabling boxes (unless the user manually
enters the advanced option to remove it), and the above two times will also be automatically
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7.6. MODBUS UNDER MULTI-DESTINATION IP
8. REGISTRATION PACKAGE AND HEARTBEAT PACKAGE
configured according to the baud rate . However, if the user's Modus command is relatively long
or the conversion protocol is "None", these two parameters need to be configured manually.
The following describes the recommended settings of the above parameters:
1.
Figure 30 shows the "RS485 bus anti-collision time". Generally, it can be set to twice the
"Packet Interval" in the lower right corner of the parameter configuration interface, but the
minimum should not be less than 20.
2.
Figure 29 shows the "RS485 command response timeout", which is generally
determined according to the length of the back and forth response command. If the sending
command is N bytes and the response is M bytes, the recommended value is: "Packet interval"
×(N+M+5)+100.
As shown in Figure 28, if the serial device (RTU device) is used as the master station and
the network port device (Modbus TCP device) is used as the slave station, and there are
multiple network port slave devices at the same time. At this time, you can use the method
described in 5.2.2 Client Connecting Multiple Servers to let the serial port server as a client
connect to these multiple network port devices at the same time.
The function that needs to be realized at this time is: when the serial port RTU sends a
command, it can be sent to multiple network port devices, the network port device recognizes
whether to send it to itself through the Slave ID field, and only the network port device
corresponding to the Slave ID responds. After the network port response is sent to the serial
server, it is converted into an RTU command and output from the serial port to the RTU device.
At this time, it should be noted that it is necessary to remove the two checkmarks shown
in Figure 30 as "RS485 bus anti-collision time" and Figure 29 as "RS485 command response
timeout time". Otherwise, the above forwarding function cannot be realized. Another
application method is: Although the serial server is connected to multiple network port devices
as a Client, the RTU device is not the master station, and the network port device still sends it
first, and the RTU device responds (as a slave station). At this time, the "RS485 bus anticollision time" and "RS485 command response timeout time" still need to be checked, so that
multiple hosts can access one RTU device at the same time.
The registration package and the heartbeat package are suitable for
communication between the device and the cloud software.
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8.1. REGISTRATION PACKAGE
The definition of the registration package is that when the computer software and the
serial server module (hereinafter referred to as the module) establish a TCP connection, the
module will send a string of codes to the software at first, so that the software can recognize
which module is communicating with. This string of codes is the registration package.
The registration package is very suitable for monitoring the Internet of Things, because
the cloud software generally runs on the public network server of the Internet, and the
modules are distributed at various collection and monitoring spots. It is essential to recognize
the module for the cloud software, which is necessary for realizing the IoT communication.
The serial server provides the following multiple registration package methods.
8.1.1.SEND MAC ADDRESS ON CONNECTION
Send the MAC address on the connection: This method is not only supported for 4 models
(such as RS485 TO ETH (B)), but also for ordinary models. Its method is to send its mac address
to the cloud when the module is connected to the cloud. Since the MAC address is unique, it
can identify the corresponding device. This method is simple and does not require writing a
registration package for each device, so it is simple and effective. How to use it: Click "More
Advanced Settings" in the device settings dialog box, find "Send MAC address when TCP is
establish" in the upper middle, tick the front, and then return to the setting interface and click
"Modify Settings".
8.1.1.
REALCOM AGREEMENT
Figure 31 Sending MAC address on connection
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The Realcom protocol is a protocol containing a registration package and a heartbeat package.
Users can use this protocol to realize the functions of the registration package and heartbeat
package. The method to enable the Realcom protocol is: in the "Device Settings" dialog box,
select "Conversion Protocol" to "REAL_COM Protocol", and note that the part of enabling the
registration package needs to be blank and unchecked.
Figure 32 Enable realcom protocol
After the Realcom protocol is enabled, it will not be transparent transmission
communication. It has the following characteristics:
1. After the device establishes a TCP connection with the cloud, the device automatically
sends a hexadecimal registration packet FA 07 13 02 FA 02 MAC[5] MAC[4] MAC[3] MAC[2]
MAC[1] MAC[0 ] FA FF. Among them, MAC[5]~MAC[0] is the MAC address of the device.
2. When the device sends data to the network, it will automatically add the 3-byte header
prefix of FA 01 01.
3. Every keep-alive timing interval, the device sends a 00 1-byte heartbeat packet to the
software. The REAL_COM protocol can be used as a device registration package because it
contains the MAC address in the registration package. However, due to its fixed format, only
the cloud software can design the REALCOM protocol to be compatible with this method
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8.1.2.
CUSTOM REGISTRATION PACKAGE
The custom registration package method is that the user can fill in an arbitrary registration
package format. The method is: in the device setting interface, the configuration is as follows:
Figure 33 Set registration package
The difference with the REAL_COM protocol is that the registration package is enabled here,
and the registration package information such as 31 32 33 34 is filled in. Note that this is
hexadecimal, that is, the actual data sent is the string 1234. If you need to display a string, click
the "ASCII" option next to it.
When the device is connected to the cloud software, it can automatically send the
hexadecimal registration package of 31 32 33 34. This registration package method is more
flexible, allowing the device to adapt to the existing cloud registration package format; however,
there is no wildcard such as MAC in the registration package, and different registration packages
need to be configured separately for each device, which is more cumbersome. The above two
methods of sending MAC address and REALCOM have the same configuration for each device,
but the registration package is naturally different due to different MACs.
The longest registration packet length is 33 bytes. This method supports registration packets
and heartbeat packets in UDP mode.
8.1.3.
CONFIGURATION FILE
Support serial server to write a configuration file, so as to realize user-defined registration
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package, and can use MAC address wildcard, which can solve the trouble of writing custom
8.2. HEARTBEAT PACKAGE
registration package for each device, and there is no limit to the length of registration package.
The heartbeat packet is mainly used to detect whether the communication link is
disconnected. The method of implementation is that the device sends a heartbeat packet data to
the server software at regular intervals. This data will be deleted after being received by the
server and will not be regarded as valid communication data.
The heartbeat packet has two main functions: First, it can let the host computer software
know that the device is active; secondly, if the device fails to send the heartbeat, the device at
the TCP client will automatically re-establish the TCP connection, so it is a recovery network
communication A means.
As shown in Figure 34, the sending time of the heartbeat packet is set by the "Keep Alive
Time".
8.2.1.
Even if you don't set any heartbeat packets, the implicit heartbeat function will be enabled
when the Waveshare device is on the TCP client.
Therefore, the implicit heartbeat function means that the device sends data, but the server
cannot actually receive the heartbeat data. Therefore, it cannot play the first function of the
heartbeat packet, that is, the server detects whether the device is active or not; but because the
Figure 34 Keep Alive Time
IMPLIED HEARTBEAT
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9. REMOTE DEVICE MANAGEMENT
device actually sends data, it can play the second function of the heartbeat packet, that is, the
device detects the TCP connection is normal, once the disconnection is detected, the TCP
connection can still be automatically re-established.
8.2.2.
REALCOM PROTOCOL
As described in 8.1.2 Realcom protocol, REALCOM protocol can send a 1-byte data of 00
every keep-alive time. This data is the heartbeat packet of realcom protocol.
8.2.3.
CUSTOM HEARTBEAT PACKAGE
First, fill in the registration package according to the method of 8.1.3 customizing the
registration package. Then add the heartbeat packet as follows: Click the "More Advanced
Settings" button in the device settings, write the hexadecimal heartbeat packet in the second
line of the multi-destination IP and port, and change the option on the right to "Param. Dest".
Figure 35 Customized registration package
Note that the sum of the registration packet and the heartbeat packet should be less than
33 bytes. The first line is actually the registration package.
The so-called remote device management refers to the ability to maintain and manage the
device through Vircom software, including restarting the device, modifying parameters, and
upgrading firmware. This function is suitable for users who use Vircom for device management.
For Vircom software, as long as the device can be found in the device list, it can be managed
remotely. The remote management of equipment is divided into the following situations:
1.
Automatic search: The device and the computer are on the same switch. At this time, no
matter whether they are in the same network segment or not, the Vircom search method on the
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computer is: Vircom sends a broadcast query. After receiving the query, all devices will reply with
their own parameters. Vircom tools. This method searches all devices at once.
2.
Manually add: There are two situations:
a)
Large-scale routers divide the network: In some large-scale networks, broadcast packets
are divided by routers, so that the broadcast packets cannot reach the device end, but the ping
device IP is all connected. At this time, it generally needs to be added manually to solve the
problem. The method of adding manually is to click "Add manually" in the "Device Management"
dialog box to add the first and last IP to query the devices one by one.
b)
The public network server queries the internal network equipment: the serial port server
is in the internal network and acts as a TCP server mode, and Vircom is on the public network IP
server. At this time, you need to do a 1092 UDP port mapping on the router of the network
where the device is located, and map it to the IP where the device is located, and then Vircom
manually adds the device. The IP is the public network IP of the device.
3.
TCP client: When the device acts as a TCP client, it will initiate a TCP connection to port 4196
of the destination IP (116.15.2.3). After the connection is established, it will automatically send
its own parameter system to the UDP port (note that it is not the TCP port) of the destination
port (here 4196) at each keepalive timing, so that Vircom can be able to do so on this computer
(116.15.2.3) The device is found. If the destination port is not 4196, you need to modify the
Vircom's default parameter receiving port. The method is to modify the
menu/configuration/software configuration/default listening port, and then start Vircom. If a
TCP port conflict pops up, just ignore it and continue execution.
4.
Sending parameters at regular intervals: Even in a serial server in TCP server mode, you can
check the "Send parameters at regular intervals" function, and the parameters will be sent to the
destination port of the destination IP (here 116.15.2.3) every 5 minutes. Vircom that receives
parameters on this port of this server can manage these devices.
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10. MQTT AND JSON
11. FIRMWARE UPGRADE METHOD
Figure 39 Timing sending parameters
In order to facilitate the identification of the device, if you need to perform remote
management, please give the device a name that is easy to remember.
For related usage, please refer to： MQTT and JSON Manual
RS485 TO ETH (B) can upgrade their own programs, but not mutually upgrade programs.
Whether it is by automatic search, manual addition, or P2P search or other methods found in
the device list, you can use this method to upgrade the firmware.
1
Obtain the firmware file of RS485 TO ETH (B) from Waveshare.
2
Search for the device that needs to be upgraded in Vircom tool at first, and then enter the
device parameter editing dialog box. Click on "Restart Dev".
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Figure 40 Restart the device
After the device restarts, use the same method to search for the device again, and enter this
dialog box again. Click the "Firmware/Config" button in the lower right corner of the dialog box.
Figure 41 Upgrade firmware
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3
As shown in Figure 42, select the "Program File Download" option. In the program file, select
the firmware file. The IP address part of the serial server has been filled in automatically, and
there is no need to write it again. The module type/model has been automatically selected. Then
click download.
Figure 42 RS485 TO ETH (B) firmware upgrade method
4
By now, the download progress bar starts to move, and the download time is about 30
seconds. During the download, you will see the ACT light of the device flashing, and at the end of
the download, you will see the LINK light flashing a few times. Then the program pops up a
prompt box "Do not power off the device when the LINK light flashes after the transmission is
complete". Note: This is only the completion of the transfer. The flash writing process takes
about 3 seconds. At this time, the LINK light will flash. Please do not cut off the power during this
period.
5
After the download is complete, the general program will restart automatically, and there is
generally no need to cut off the power. If you see the running indicator flashing, if it does not
restart automatically, please stop flashing the LINK indicator for more than 30 seconds, and then
power on again.
6
Web configuration interface update: After firmware upgrade, the internal configuration
webpage of the module also needs to be updated, otherwise it will no longer be able to
configure via Web, but it will not affect communication. It is not necessary to download the web
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page if there is no need for web configuration. The way to download the Web is: as shown in
Figure 43, change the "program file" download mode to "web directory download". And select
the root directory where the local webpage is located as the directory where the webpage file to
be downloaded is located (the directory from Waveshare), click download, and download all the
files in the local webpage directory to the internal file system of the device.
Figure 43 RS485 TO ETH (B) web upgrade method
7
Notice:
7.1
If it prompts that the download failed and the device will not be damaged, please restart
the download. In addition, at the end of the download, when the LINK light is flashing, do not
power off, otherwise the device will be damaged.
7.2
Check the firmware version number by Vircom, and you can know whether the new
firmware has been downloaded successfully.
Figure 50 Check the firmware version after the level is completed
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