Ebyte NB183 User manual

Chengdu Ebyte Electronic Technology Co.,Ltd. NB183S&NB183_User Manual
Copyright ©2012–2022，Chengdu Ebyte Electronic Technology Co.,Ltd.
1
NB183
Eight Serial Port Server User Manual

Chengdu Ebyte Electronic Technology Co.,Ltd. NB183S&NB183_User Manual
Copyright ©2012–2022，Chengdu Ebyte Electronic Technology Co.,Ltd.
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Content
Disclaimer........................................................................................................................................................................................................................................4
1. Overview ..................................................................................................................................................................................................................................... 5
1.1 Features .................................................................................................................................................................................................5
2. Quick Start .................................................................................................................................................................................................................................. 6
2.1 Hardware Preparation ...........................................................................................................................................................................6
2.2 Software Preparation .............................................................................................................................................................................7
2.3 Test steps of device default parameters............................................................................................................................................7
2.3.1 Connecting the hardware ..............................................................................................................................................................7
2.3.2 Device parameter configuration ................................................................................................................................................. 7
2.3.3 Turn off the computer firewall ....................................................................................................................................................8
2.3.4 Open "Serial Debug Assistant" ...................................................................................................................................................9
2.3.5 Open Network Assistant ...............................................................................................................................................................9
2.3.6 Send and receive data test ..........................................................................................................................................................10
3. Product Overview ...................................................................................................................................................................................................................10
3.1 Technical parameters..........................................................................................................................................................................10
3.2 Interface description ........................................................................................................................................................................... 12
3.3 Indicator light description................................................................................................................................................................. 14
3.4 Dimensions ........................................................................................................................................................................................... 16
4. Basic Functions ....................................................................................................................................................................................................................... 17
4.1 Correspondence between channel and serial port....................................................................................................................... 17
4.2 Local network parameters .................................................................................................................................................................17
4.2.1 Local IP ..........................................................................................................................................................................................17
4.2.2 DNS (Domain Name Resolution)............................................................................................................................................17
4.2.3 Network disconnection and reconnection cycle ...................................................................................................................17
4.2.4 Timeout restart (no data restart)...............................................................................................................................................17
4.3 Hardware reset to factory .................................................................................................................................................................. 18
4.4 Device working mode ........................................................................................................................................................................ 18
4.4.1 TCP Server .................................................................................................................................................................................... 18
4.4.2 TCP Client .....................................................................................................................................................................................18
4.4.3 UDP Server................................................................................................................................................................................... 18
4.4.4 UDP Client.................................................................................................................................................................................... 18
4.4.5 HTTP Client..................................................................................................................................................................................19
4.4.6 MQTT Client................................................................................................................................................................................ 21
4.5 Channel ports ........................................................................................................................................................................................24
5. Advanced Functions...............................................................................................................................................................................................................25
5.1 Heartbeat package and registration package ................................................................................................................................ 25
5.1.1 Heartbeat Packet.......................................................................................................................................................................... 25
5.1.2 Registration Package.................................................................................................................................................................. 25
5.2 Short connection ..................................................................................................................................................................................25
5.3 Serial port cache cleaning ................................................................................................................................................................. 26
5.4 Modbus Gateway .................................................................................................................................................................................26
5.4.1 Protocol Conversion ................................................................................................................................................................... 26

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5.4.2 Simple Protocol Conversion .....................................................................................................................................................26
5.4.3 Multi-host mode...........................................................................................................................................................................28
5.4.4 Storage Gateway ..........................................................................................................................................................................29
5.4.5 Configurable Gateway ................................................................................................................................................................30
5.4.6 Automatic upload .........................................................................................................................................................................31
5.5 Firmware Upgrade .............................................................................................................................................................................. 32
5.5.1 UDP upgrade.................................................................................................................................................................................32
5.5.2 Serial port upgrade...................................................................................................................................................................... 33
Revision history........................................................................................................................................................................................................................... 35
About us ......................................................................................................................................................................................................................................... 35

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Disclaimer
EBYTE reserves all rights to this document and the information contained herein.
Products, names, logos and designs described herein may in whole or in part be
subject to intellectual property rights. Reproduction, use, modification or disclosure to
third parties of this document or any part thereof without the express permission of
EBYTE is strictly prohibited.
The information contained herein is provided “as is” and EBYTE assumes no
liability for the use of the information. No warranty, either express or implied, is given,
including but not limited, with respect to the accuracy, correctness, reliability and
fitness for a particular purpose of the information. This document may be revised by
EBYTE at any time. For most recent documents, visit www.ebyte.com.

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1. Overview
The serial server series products independently developed by Ebyte integrate the TCP/IP protocol stack, which can
realize two-way transparent transmission of data from serial port to Ethernet port, Modbus protocol conversion, serial
port device cloud and other functions. The industrial design ensures the stability of the equipment in the harsh working
environment, and the rich indicator light effects are used to feedback the different working states of the equipment.
It supports the configuration of the host computer. With simple configuration, the networking and cloud access of serial
devices can be easily realized.
Widely used in computer room monitoring, environmental monitoring, intelligent transportation, gate control, intelligent
express cabinet and other industries.
1.1 Features
Industrial design is stable and reliable, high-level port protection;
Abundant LED status indicators to quickly locate the working status of the equipment;
Support terminal or DC head power supply, 8-28V DC wide voltage input, support reverse connection protection;
Support terminal interface (RS485) and standard DB9 interface (RS232);
Baud rate supports 2400～115200bps, supports multiple verification methods;
Support a variety of registration packets and heartbeat packet sending, such as connecting to send MAC,
connecting to send custom, etc.;
Support stable and reliable host computer and AT command configuration, independent configuration of eight
channels does not affect each other;
Support configurable domain name resolution service, namely DNS;
Support DHCP to dynamically obtain IP, subnet mask, default gateway, DNS server address;
Support multiple working modes TCP client, TCP server, UDP client, UDP server, MQTT client, HTTP client;
Can open 8-way server mode at the same time, support 16 clients to dynamically allocate access, a single server
supports 9 client access,
Support the UDP server mode of memory mode, record the UDP address of the last communication, and use it for
the destination address of the next communication;
Support a variety of Modbus gateways, which can realize the active reporting of RTU devices, support the
inter-conversion of Modbus TCP and Modbus RTU protocols, can be configured to automatically collect device
data in storage mode, and can also use multi-host mode with one question and one answer;
Support MQTT gateway function, quickly access Alibaba Cloud and standard MQTT3.1.1 servers (OneNET,
Baidu Cloud, Huawei Cloud, etc.);
Support Modbus data to actively report TCP transparent transmission server, MQTT server and other servers;
Support HTTP client mode, use HTTP/1.1 protocol, can be configured as GET, POST two request methods

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Can use TCP/IP direct communication or connect communication through "virtual serial port";
Rich independent LED status indicators, support status feedback such as link, network cable, data transmission
and reception, and quickly locate problems;
Support firmware upgrade or firmware replacement by the host computer through UDP or serial port;
The isolated version supports 8-channel serial port independent hardware isolation(Supported only on NB183)
2. Quick Start
2.1 Hardware Preparation
One notebook with RJ45 network port;
One NB183/NB183S serial server;
One DC12V 1A power adapter;
a network cable;
One USB to RS485 serial cable;
The specific hardware equipment is prepared as shown in the following figure:
Computer
cable
NB183
DC 12V1A
USB to RS45
several wires
【Note】Only use the RS485 interface for demonstration, and use the corresponding USB converter for other interfaces;

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2.2 Software Preparation
Serial debugging assistant (XCOM), network debugging assistant (TCP/IP debugging assistant), Ebyte network
configuration tool (configuring the host computer), official website address: www.ebyte.com, product details provide
download interface.
Network Assistant
XCOM
亿佰特网络配置工具
[Note] The host computer displayed in the manual may be different from the superior version provided on the official
website. The host computer provided on the official website shall prevail.
2.3 Test steps of device default parameters
Different channels use the same IP and different local ports. For example, the factory-configured channel 1 corresponds
to port 8001 and channel 8 corresponds to port 8008 in turn. For details, see the "Correspondence between Channels and
Serial Ports" chapter.
2.3.1 Connecting the hardware
1. Use a network cable to connect the serial port server network port and the computer network port;
2. Use a USB to RS485 serial cable to connect the USB port of the computer and the RS485 interface of the serial server;
3. Use the power adapter (DC 8-28V) to power on the device, and observe whether the indicator light is normal after
power-on, refer to "Indicator Indicator";
4. After confirming that there is no problem with the status, proceed to the next configuration;
2.3.2 Device parameter configuration
In order to enable users to quickly have a simple understanding of the serial port server, we use the default parameters of
the serial port server to conduct data transparent transmission test. The default parameters of the NB183 serial server
device are shown in the table below.
Project
default parameters

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IP address
192.168.3.7
subnet mask
255.255.255.0
gateway
192.168.3.1
The working mode of channel
1
TCP_SERVER
The working mode of channel
1
8001
Serial port baud rate
115200
Serial port parameters
NONE/8/1/NONE
Make sure that the IP of the computer and the IP of the serial port server are in the same network segment and cannot
conflict. The inspection method is shown in the figure below.
2.3.3 Turn off the computer firewall
If the communication is unsuccessful, the user can try to turn off the firewall of the computer and try again.

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2.3.4 Open "Serial Debug Assistant"
Select the correct serial port number, configure the correct serial port parameters (115200-8N1), and open the serial port,
as shown in the following figure:
2.3.5 Open Network Assistant
Select "TCP Client" mode, configure the remote IP as "192.168.3.7", and configure the remote port as "8001" as shown
in the following figure:

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2.3.6 Send and receive data test
Click the [Send] button on the "Network Debugging Assistant" and "Serial Debugging Assistant" respectively to realize
the transparent transmission of network and serial data, as shown in the figure below.
3. Product Overview
3.1 Technical parameters
project
interface
explanation
Power
crimp terminal
DC 8～28 V, can not input power at the same time;

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Crimping terminal: 5.08mm*2 phoenix terminal;
DC female head: in-line round hole, outer diameter
5.5mm, inner diameter 2.0mm;
DC female
network port
RJ45
10M
serial port
Channel 1 to
Channel 4
Interface 1 (RS485, 3.81mm phoenix terminal, support
isolation);
Interface 2 (RS232, standard RS232 line sequence DB9
female)；
Channel 5 to
Channel 8
RS485, 3.81mm Phoenix terminal, support isolation
Operating mode
TCP Server、TCP Client、UDP Server、UDP Client、HTTP Client、MQTT Client
（default TCP Server）
Network
protocol
IP、TCP/UDP、IPv4、ICMP、APR、DHCP、DNS、HTTP、MQTT
How to get IP
DHCP、Static IP (default static IP)
DNS
support
Configuration
method
Configuration tools, AT commands
IP address
Customizable (default, 192.168.3.7)
local port
Customizable (default, channel 1 to channel 8: 8001-8008)
subnet mask
Customizable (default, 255.255.255.0)
gateway
Customizable（default，192.168.3.1）
Serial port cache
512 Byte
Serial port
packaging
mechanism
512 Byte
Serial port baud
rate
2400 ～115200 bps（default115200）
data bits
8
stop bit
1, 2 (default 1)
Check Digit
None、Odd、Even（defaultNone）
Flow Control
not support
Installation
method
Positioning hole installation
Product Size
198mm * 109mm * 26.5mm （length*width*height）
product weight
518g ± 5g
Working
temperature and
humidity
-40 to +85℃, 5% to 95%RH (non-condensing)
Storage
temperature and
humidity
-40 ~ +105℃, 5% ~ 95%RH (non-condensing)

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3.2 Interface description
No
Name
Function
Explanation
1
RS485-1-A
channel1-RS485
InterfaceA
3.81mm Phoenix Terminal
2
RS485-1-B
channel1-RS485
InterfaceB
3.81mm Phoenix Terminal
3
RS485-1-G
channel1-RS485
InterfaceG
3.81mm Phoenix Terminal
4
RS485-2-A
channel2-RS485
InterfaceA
3.81mm Phoenix Terminal
5
RS485-2-B
channel2-RS485
InterfaceB
3.81mm Phoenix Terminal
6
RS485-2-G
channel2-RS485
InterfaceG
3.81mm Phoenix Terminal
7
RS485-3-A
channel3-RS485
3.81mm Phoenix Terminal

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InterfaceA
8
RS485-3-B
channel3-RS485
InterfaceB
3.81mm Phoenix Terminal
9
RS485-3-G
channel3-RS485
InterfaceG
3.81mm Phoenix Terminal
10
RS485-4-A
channel4-RS485
InterfaceA
3.81mm Phoenix Terminal
11
RS485-4-B
channel4-RS485
InterfaceB
3.81mm Phoenix Terminal
12
RS485-4-G
channel4-RS485
InterfaceG
3.81mm Phoenix Terminal
13
RS485-5-A
channel5-RS485
InterfaceA
3.81mm Phoenix Terminal
14
RS485-5-B
channel5-RS485
InterfaceB
3.81mm Phoenix Terminal
15
RS485-5-G
channel5-RS485
InterfaceG
3.81mm Phoenix Terminal
16
RS485-6-A
channel6-RS485
InterfaceA
3.81mm Phoenix Terminal
17
RS485-6-B
channel6-RS485
InterfaceB
3.81mm Phoenix Terminal
18
RS485-6-G
channel6-RS485
InterfaceG
3.81mm Phoenix Terminal
19
RS485-7-A
channel7-RS485
InterfaceA
3.81mm Phoenix Terminal
20
RS485-7-B
channel7-RS485
InterfaceB
3.81mm Phoenix Terminal
21
RS485-7-G
channel7-RS485
InterfaceG
3.81mm Phoenix Terminal
22
RS485-8-A
channel8-RS485
InterfaceA
3.81mm Phoenix Terminal
23
RS485-8-B
channel8-RS485
InterfaceB
3.81mm Phoenix Terminal
24
RS485-8-G
channel8-RS485
InterfaceG
3.81mm Phoenix Terminal
25
-
Negative pole of DC 8-28
V
DC 8-28 V, 2*5.08mm phoenix terminal input;
Do not supply power at the same time as the
socket；
26
+
Positive pole of DC 8-28 V
DC 8-28 V, 2*5.08mm phoenix terminal input;
Do not supply power at the same time as the
socket;
27
DC-IN
DC power input
DC 8-28 V;
In-line round hole, outer diameter 5.5mm, inner

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diameter 2.5mm;
Do not supply power with the terminals at the
same time;
28
Ethernet
Ethernet Interface
Standard RJ45 Ethernet Interface, 10/100M
adaptive
29
Reload
Factory reset button
After long press for 5s, NET is always on for 5s,
and the device is reset to factory
30
RS232-4
channel4-RS232 Interface
Standard DB9 female, 2-TXD, 3-RXD, 5-GND
31
RS232-3
channel3-RS232 Interface
Standard DB9 female, 2-TXD, 3-RXD, 5-GND
32
RS232-2
channel2-RS232 Interface
Standard DB9 female, 2-TXD, 3-RXD, 5-GND
33
RS232-1
channel1-RS232 Interface
Standard DB9 female, 2-TXD, 3-RXD, 5-GND
3.3 Indicator light description
Label
Function
Explanation
POWER
Power Indicator
DC 8-28V power input
NET
Running lights
Unconnected network cable: 100ms on and 900ms off, flashing
periodically;
Connect the network cable: 1s is a period of flashing;
PORT1
Channel 1 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT2
Channel 2 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT3
Channel 3 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；

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UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT4
Channel 4 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT5
Channel 5 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT6
Channel 6 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT7
Channel 7 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
PORT8
Channel 8 Status
Indicator
The link is not connected: the indicator light is off;
The link connection is successful: the indicator light is always
on；
UDP mode: the indicator light is always on；
Data sending and receiving indication: flashes when network or
serial port sends and receives data;
[Note] The status of some special working mode indicator lights:
1. Restore the factory, NET is always on for 5s, and the other indicators remain in the state until the NET goes out and then goes out;
2. Wait for the firmware to be burned, and the rest of the lights except the power indicator will flash with a cycle of 50ms, until the
upgrade file starts to be transferred, or the firmware burning is exited;
3. During the firmware burning operation, the other indicators except the power indicator flash in a cycle of 500ms until the upgrade is
completed;

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3.4 Dimensions

4. Basic Functions
4.1 Correspondence between channel and serial port
Baud rate: 2400, 4800, 9600, 14400, 19200, 38400, 57600, 76800, 115200bps;
Data bits: only 8 bits are supported;
Check digit: support no check (NONE), odd check (ODD), even check (EVEN);
Hardware flow control: not supported
Channel
Serial Port
pilot lamp
Serial protocol
Factory port, mode
Channel1
COM1
PORT1
RS232、RS485
8001、TCPS
Channel2
COM2
PORT2
RS232、RS485
8002、TCPS
Channel3
COM3
PORT3
RS232、RS485
8003、TCPS
Channel4
COM4
PORT4
RS232、RS485
8004、TCPS
Channel5
COM5
PORT5
RS485
8005、TCPS
Channel6
COM6
PORT6
RS485
8006、TCPS
Channel7
COM7
PORT7
RS485
8007、TCPS
Channel8
COM8
PORT8
RS485
8008、TCPS
4.2 Local network parameters
4.2.1 Local IP
STATIC (Static IP): Users can define configuration IP, subnet mask, default gateway, domain name resolution server
(DNS server);
DHCP (Dynamic IP Acquisition): The device logs in to the server to automatically obtain the IP address, subnet mask,
gateway address, and DNS server address parameters assigned by the server and configure and use
4.2.2 DNS (Domain Name Resolution)
When the user enters the domain name, the DNS server will be automatically queried, the database will be retrieved by
the DNS server, and the corresponding IP address will be obtained. In the static IP mode, the user can customize the
domain name resolution server, which is used to resolve the private domain name server data. In the dynamic IP mode
The device automatically follows the domain name resolution server configured by the routing device. Users only need
to modify the DNS server of the routing device without configuring the device.
4.2.3 Network disconnection and reconnection cycle
When the device detects that it is disconnected from the server, it periodically initiates a reconnection request. Therefore,
the "disconnection reconnection time" does not affect the connection establishment time under normal conditions. The
user can customize the configuration request period, and the default is 5s.
4.2.4 Timeout restart (no data restart)
The device monitors the data sending and receiving status. If the device does not send and receive data for a long time,
the device automatically restarts to ensure the stability of long-term work. The default turn-on period of this function is 5

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minutes, and the user can customize the turn-on or turn-off timeout restart period or the period of no data restart.
4.3 Hardware reset to factory
Press and hold the Reload pin of the device for 5s until the NET indicator no longer flashes, keep the NET indicator on
for 5s, and the device is restored to the factory.
4.4 Device working mode
4.4.1 TCP Server
TCP Server is the TCP server. In TCP Server mode, the device listens to the local port, accepts the client's connection
request and establishes a connection for data communication. When the Modbus gateway function is turned off, the
device sends the data received by the serial port to all client devices that establish a connection with the device.
The number of clients that can be accessed by the server is dynamically adjusted. First, ensure that each channel of the
eight channels can establish a complete communication link. In addition, the device also has 8 dynamic access
communication links. For example, if the device turns on the eight-channel server mode, each server Two client devices
can be connected, or if one server is enabled on the device, the server can connect to 9 client devices. If the number of
client devices exceeds the number of accesses, the device will refuse the connection.
4.4.2 TCP Client
TCP Client is the TCP client. When the device is working, it will actively initiate a connection request to the server and
establish a connection to realize the interaction between serial port data and server data.
To use the client, you need to configure the target IP address/domain name and target port accurately.
Eight channels can independently open eight TCP clients.
4.4.3 UDP Server
UDP Server means that the device does not verify the IP address of the data source when communicating with the UDP
protocol. After each UDP data packet is received, it saves the source IP address and source port of the data packet, and
sets it as the destination IP and port, so The data sent by the device only sends data packets to the source IP address and
port where the device received data last time.
This mode is usually used in scenarios where multiple network devices communicate with this device, and the frequency
is high, and the TCP Server cannot meet the conditions.
Using UDP Server requires the remote UDP device to send data first, otherwise the data cannot be sent normally.
[Note] In UDP mode, the data sent by the network to the device should be less than 512Bit per packet, otherwise it will
cause data loss.
4.4.4 UDP Client
UDP Client is a connectionless transmission protocol that provides transaction-oriented simple and unreliable
information transmission services. There is no connection establishment and disconnection, and data can be sent to the
other party only by configuring the destination IP and destination port. It is usually used in data transmission scenarios
where there is no requirement for the packet loss rate, the data packets are small and the transmission frequency is fast,
and the data is to be transmitted to the specified IP.
In UDP Client mode, the device will only communicate with the configured (target IP and target port) remote UDP

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devices.
In this mode, the target address is set to 255.255.255.255, and the sent data will be broadcast on the entire network
segment, but the transceiver device needs to ensure that the ports are consistent, and the device can also receive broadcast
data.
[Note] In UDP mode, the data sent by the network to the device should be less than 512Bit per packet, otherwise it will
cause data loss.
4.4.5 HTTP Client
This mode can realize the function of HTTP automatic packet grouping. It provides two methods: GET and POST.
Customers can configure URL, Header and other parameters by themselves, and the device will send packets to achieve
fast communication between serial data and HTTP server. URL and Header are the most important. It supports 128 bytes
of data for a long time, and the eight channels can independently open the HTTP client mode without affecting each
other.
The HTTP request data should be less than the packet length (512 bytes), otherwise the device will divide the request
data into multiple packets for request, resulting in abnormal request.
Supports configuring whether to return HTTP protocol headers. The returned data is shown in the following figure:

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Configuration instructions, open the host computer, search for the device and enter the device configuration interface,
first configure the "network parameters", it is recommended to use the DHCP function to avoid incorrect configuration
leading to abnormal device IP (network segment error, IP conflict, etc.), you need to use the HTTP function in the
configuration It supports eight channels and configures HTTP client mode at the same time. Here is an example of
requesting a "Baidu" webpage through GET (URL: empty, HEADER: Host: www.baidu.com, target domain name:
www.baidu.com, target Port: 80, the local port is recommended to use a random port), the specific configuration is shown
in the following figure:
The request data is "/", use the serial port assistant to get the webpage: