Ebyte ME31-XXXA0006 User manual

ME31-XXXA0006
Network I/O Networking Module
This manual may be updated with product improvements, please refer to the latest version of the
manual! Chengdu Yibaite Electronic Technology Co., Ltd. reserves the final interpretation and
modification rights for all contents in this instruction!

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Contents
I. Overview .......................................................................................................................................... 3
1.1 Product Introduction .........................................................................................................................................3
1.2 Functional Features .......................................................................................................................................... 3
1.3 Product Application Topology Diagram .......................................................................................................... 3
II.Quick use .................................................................................................................................................................... 5
2.1 Device preparation ........................................................................................................................................... 5
2.2 Device connection ............................................................................................................................................ 6
2.2.1 RS485 connection ................................................................................................................................. 6
2.2.2 AO analog output connection ................................................................................................................6
2.2.3 Simple use ............................................................................................................................................. 7
2.3 Parameter Configuration .................................................................................................................................. 7
2.4 Control Testing ................................................................................................................................................. 8
2.4.1 Modbus TCP control ............................................................................................................................. 8
2.4.2 Modbus RTU control .............................................................................................................................9
III. Technical Specification .......................................................................................................................................... 10
3.1 Specifications ................................................................................................................................................. 10
3.2 Device Default Parameters .............................................................................................................................10
3.3 Mechanical Dimensional Drawing .................................................................................................................11
3.4 Port and indicator light description ................................................................................................................12
IV. Product Function Introduction ................................................................................................................................14
4.1 AO output ....................................................................................................................................................... 14
4.1.1. AO output range ................................................................................................................................. 14
4.2 Modbus Gateway ............................................................................................................................................14
4.2.1. Modbus TCP/RTU protocol conversion ............................................................................................ 14
4.2.2. Modbus Address Filtering ..................................................................................................................14
4.2.3. Modbus TCP Protocol Data Frame Description ................................................................................ 14
4.2.4. Modbus RTU protocol data frame description .................................................................................. 15
4.3 Custom Module Information ..........................................................................................................................15
4.3.1. Modbus Address .................................................................................................................................15
4.3.2. Module Name .....................................................................................................................................15
4.3.3. Network parameters ........................................................................................................................... 15
4.3.4. Serial Port Parameters ........................................................................................................................ 16
4.4 OLED display and parameter configuration .................................................................................................. 16
4.4.1. Information Display Interface ............................................................................................................17
4.4.2. Equipment parameter display interface ............................................................................................. 17
4.4.3. Equipment Parameter Configuration Interface .................................................................................. 17
4.4.4. Screen Sleep ....................................................................................................................................... 18
4.5 MODBUS parameter configuration ............................................................................................................... 18
4.5.1. AO Register List .................................................................................................................................18
4.5.2. Module related registers .....................................................................................................................19
4.5.3. Network related registers ................................................................................................................... 19

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4.5.4. Examples of Modbus command operation instructions .....................................................................20
V. Configuration Software ............................................................................................................................................23
5.1. Acquisition and Control ................................................................................................................................ 23
5.2. Parameter configuration interface .................................................................................................................24

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I. Overview
1.1 Product Introduction
ME31-XXXA0006 is a network I/O networking module with 6 analog outputs
(0-20mA/4-20mA) and supports Modbus TCP protocol or Modbus RTU protocol
for acquisition and control. The device can also be used as a simple Modbus
gateway (automatically send commands with non-local Modbus addresses through
the serial port/network port).
1.2 Functional Features
Support standard Modbus RTU protocol and Modbus TCP protocol;
Support various configuration software/PLC/touch screen;
RS485 acquisition control I/O;
RJ45 acquisition control I/O, support 4-way host access;
Support OLED display to display status information, and configure device parameters through buttons;
6 analog outputs (0-20mA/4-20mA)；
Support custom Modbus address setting;
Support 8 common baud rate configurations;
Support DHCP and static IP;
Support DNS function, domain name resolution;
Support Modbus gateway function;
1.3 Product Application Topology Diagram
Network interface application topology diagram

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Serial port application topology diagram

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II.Quick use
【Note】This test needs to be carried out with the default factory parameters.
2.1 Device preparation
The following table lists the items required for this test:
ME31-XXXA0006
12V switching power
supply
USB to RS485 Cable
A computer
A network cable
Several cables

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2.2 Device connection
2.2.1 RS485 connection
Note: When the 485 bus high-frequency signal is transmitted, the signal wavelength is shorter than the transmission
line, and the signal will form a reflected wave at the end of the transmission line, which will interfere with the original
signal. Therefore, it is necessary to add a terminal resistor at the end of the transmission line so that the signal does not
reflect after reaching the end of the transmission line. The terminal resistance should be the same as the impedance of the
communication cable, the typical value is 120 ohms. Its function is to match the bus impedance and improve the
anti-interference and reliability of data communication.
2.2.2 AO analog output connection
RS485 wiring diagram
External power supply
ME31 Device
User’s RS485 Device
Signal Generator/Sensor

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2.2.3 Simple use
Wiring: The computer is connected to the RS485 interface of ME31-XXXA0006 through USB to RS485, A is
connected to A, and B is connected to B.
Networking: Insert the network cable into the RJ45 port and connect to the PC.
Power supply: Use DC-12V switching power supply (DC 8~28V) to power ME31-XXXA0006.
2.3 Parameter Configuration
Step 1: Modify the IP address of the computer to be consistent with the device. Here I am modifying it to
192.168.3.100 to ensure that it is on the same network segment as the device and that the IP is different. If you
cannot connect to the device after the above steps, please turn off the firewall and try again;
Step 2: Open the network assistant, select the TCP client, enter the remote host IP192.168.3.7 (default parameter),
enter the port number 502 (default parameter), and select HEX to send.
Network port

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2.4 Control Testing
2.4.1 Modbus TCP control
Use the network assistant to control the first AO output of ME31-XXXA0006 to 10mA.
Other functions can be tested through the commands in the table below.
Function (function code)
Command
Control AO1 output 10mA (0x10)
01 00 00 00 00 0B 01 10 00 00 00 02 04 41 20 00 00
Read AO1 output (0x03)
01 00 00 00 00 06 01 03 00 00 00 02
The device is in server mode, and the
computer connects to the device as a client.
Enter the IP address of the device.
Enter the port number of the device.
Select HEX display to facilitate observation
of data.
Select HEX to send

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2.4.2 Modbus RTU control
Use the serial port assistant to read the current AO1 output of ME31-XXXA0006.
Other functions can be tested through the commands in the table below.
Function (function code)
Command
Read current AO1 output (0x03)
01 03 00 00 00 02 C4 0B
Control AO1 current output 10mA (0x10)
01 10 00 00 00 02 04 41 20 00 00 E6 59

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III. Technical Specification
3.1 Specifications
Category
Name
Parameters
Power supply
Operating Voltage
DC8～28V
Power indicator
Blue LED indication
Serial port
Communication
Interface
RJ45, RS485
Baud rate
9600bps (customizable)
Protocol
Standard Modbus TCP, Modbus RTU protocol
MODBUS
Device address
Can be modified by Modbus command and host
computer
AO output
Number of AO
channels
6 way
AO output type
Current output, 2-wire connection
AO output range
0～20mA \4～20mA
AO resolution
16 bits
Output accuracy
3‰
Output indication
OLED screen display
Other
Product Size
121mm * 72mm * 34mm (L*W*H)
Product weight
135 ±5 g
Working
temperature and
humidity
-40 ～+85℃, 5% ～95%RH (no condensation)
Storage
temperature and
humidity
-40 ～+105℃, 5% ～95%RH (no
condensation)
Installation method
Din-rail installation
3.2 Device Default Parameters
Category
Name
Parameters
Ethernet parameters
Operating mode
TCP server (up to 4-way client
access)
Local IP
192.168.3.7
local port
502
Subnet mask
255.255.255.0

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Gateway address
192.168.3.1
DHCP
Close
Native MAC
Determined by the chip (fixed)
Target IP
192.168.3.3
Target port
502
DNS server
114.114.114.114
Active upload
Close
Serial parameters
Baud rate
9600bps (8 types)
Check method
None (default), Odd, Even
Data bit
8
Stop bit
1
MODBUS parameter
Modbus master-slave
Slave
Address
1
3.3 Mechanical Dimensional Drawing

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3.4 Port and indicator light description
No.
Label
Illustrate
1
TX（LED）
Serial port send data indicator light
2
RX（LED）
Serial port receiving data indicator light
3
LINK（LED）
Network connection light
4
NET（LED）
Network data sending and receiving indicator light
5
PWR（LED）
Power input indicator
6
GND
Negative pole of power input terminal, DC 8V~28V, 5.08mm Phoenix terminal.
7
VCC
Positive pole of power input terminal, DC 8V~28V, 5.08mm Phoenix terminal.
8
AO3
Analog output current (positive pole), channel 3, 5.08mm Phoenix terminal.
9
AGND
Analog output current (negative pole), channel 3, 5.08mm Phoenix terminal.
10
AO4
Analog output current (positive pole), channel 4, 5.08mm Phoenix terminal.
11
AGND
Analog output current (negative pole), channel 4, 5.08mm Phoenix terminal.
12
AO5
Analog output current (positive pole), channel 5, 5.08mm Phoenix terminal.
13
AGND
Analog output current (negative pole), channel 5, 5.08mm Phoenix terminal.
14
AO6
Analog output current (positive pole), channel 6, 5.08mm Phoenix terminal.
15
AGND
Analog output current (negative pole), channel 6, 5.08mm Phoenix terminal.
16
Ethernet
Ethernet interface, standard RJ45 interface.
17
AGND
Analog output current (negative pole), channel 2, 5.08mm Phoenix terminal.
18
AO2
Analog output current (positive pole), channel 2, 5.08mm Phoenix terminal.

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19
AGND
Analog output current (negative pole), channel 1, 5.08mm Phoenix terminal.
20
AO1
Analog output current (positive pole), channel 1, 5.08mm Phoenix terminal.
21
GND
Signal ground, 5.08mm Phoenix terminal.
22
485-A
The A of the serial port is connected to the A interface of the external device,
and the 5.08mm Phoenix terminal.
23
485-B
The B of the serial port is connected to the B interface of the external device,
and the 5.08mm Phoenix terminal.

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IV. Product Function Introduction
4.1 AO output
4.1.1. AO output range
Analog output (AO), the current output type can be configured as 0~20mA or 4~20mA, the precision is 3‰,
and the resolution is 16 bits.
The power-on default output value can be set (when the working mode is switched, the power-on value will be
output according to the lowest value of the current range).
4.2 Modbus Gateway
The device can transparently transmit non-native Modbus commands from the network/serial port to the serial
port/network, and the local Modbus commands are directly executed.
4.2.1. Modbus TCP/RTU protocol conversion
After it is turned on, the Modbus TCP data on the network side will be converted to Modbus RTU data.
4.2.2. Modbus Address Filtering
This function can be used when some host software or configuration screen is used as the host to access the
serial port of the device, and the gateway function of the device is used, the slave is at the network end, and the
Modbus TCP to RTU function is turned on. Multiple slaves on the bus may cause data confusion. At this time,
enabling address filtering can ensure that only the specified address can pass through the device; when the
parameter is 0, the data will be transparently transmitted; when the parameter is 1-255, only the set slave machine
address data.
4.2.3. Modbus TCP Protocol Data Frame Description
TCP frame format：
Transaction ID
Protocol ID
Length
Device address
Function code
Data segment
2 Bit
2 Bit
N+2 Bit
1 Bit
1 Bit
N Bit
Transaction ID: It can be understood as the serial number of the message. Generally, 1 is added after each

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communication to distinguish different communication data messages.
Protocol identifier: 00 00 means Modbus TCP protocol.
Length: Indicates the length of the next data in bytes.
Example: get DI status
01 00
00 00
00 06
01
02
00 00 00 04
Transaction ID
Protocol ID
Length
Device address
Function code
Data segment
4.2.4. Modbus RTU protocol data frame description
RTU frame format：
Device address
Function code
Data segment
Check codeCRC
1 Bit
1 Bit
N Bit
2 Bit
Example: get DI status command
01
02
00 00 00 04
79 C9
Device Modbus address
Function code
Data segment
CRC check code
4.3 Custom Module Information
4.3.1. Modbus Address
The device address is 1 by default, and the address can be modified, and the address range is 1-247.
4.3.2. Module Name
Users can configure the device name according to their own needs to distinguish, support English, digital
format, up to 20 bytes.
4.3.3. Network parameters
Unless otherwise specified: the following network-related parameters default to IPV4-related
parameters.
(1) MAC of the device: the user can obtain it by reading the specified register, and this parameter cannot be
written.
(2) IP address: device IP address, readable and writable.
(3) Modbus TCP port: the port number of the device, readable and writable.
(4) Subnet mask: address mask, readable and writable.
(5) Gateway address: gateway.

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(6) DHCP: Set the way the device obtains IP: static (0), dynamic (1).
(7) Target IP: When the device works in client mode, the target IP or domain name of the device connection.
(8) Destination port: When the device is working in client mode, the destination port of the device
connection.
(9) DNS server: The device is in the client mode and resolves the domain name of the server.
(10) Module working mode: switch the working mode of the module. Server: The device is equivalent to a
server, waiting for the user's client to connect. The maximum number of connections is 4. Client: The device
actively connects to the target IP and port set by the user.
(11) Active upload: When this parameter is not 0, and the device is in the client mode, the discrete input status
of the device will be uploaded to the server when it is connected for the first time or the input changes, and the
analog input will be uploaded according to the configured time period.
4.3.4. Serial Port Parameters
Parameters for setting serial communication:
Default parameters:
Baud rate: 9600 (03);
Data bit: 8bit;
Stop bit: 1bit;
Check digit: NONE(00);
(1) Baud rate：
Baud rate code value table
0x0000
1200
0x0001
2400
0x0002
4800
0x0003
（default）
9600
0x0004
19200
0x0005
38400
0x0006
57600
0x0007
115200
(2) Check Digit：
Check Digit
0x0000(default)
NONE
0x0001
ODD
0x0002
EVEN
4.4 OLED display and parameter configuration
The display interface includes an information display page (AO input value display page) and a parameter
setting page (some parameters).

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4.4.1. Information Display Interface
Including the AO input value display page, short press the up and down buttons to switch the interface.
4.4.2. Equipment parameter display interface
Press the left button or right button to enter the password input interface, complete the correct password input,
and the device parameter information interface will be displayed (password interface: default password: 0000; short
press the middle to verify the password, the left and right buttons switch the password bit, and the up and down
buttons switch the current bit value, the password has a total of 4 digits, and each input is a number ranging from
0-9):
The parameter setting interface from top to bottom is:
1. Modbus address;
2. Baud rate;
3. Data bits;
4. Check Digit;
5. Stop bit;
6. Local port;
7. Local IP address;
8. Gateway;
9. Subnet mask;
10. DNS;
11. MAC address;
12. DHCP;
13. Target IP;
14. Destination port;
15. Modbus TCP/RTU protocol conversion;
16. Active upload;
17. Modbus address filtering;
4.4.3. Equipment Parameter Configuration Interface
Press and hold the confirmation button to enter the password input interface, complete the correct password
input, and enter the configuration interface (password interface: default password: 0000; short press the middle to
verify the password, the left and right buttons switch the password bit, and the up and down buttons switch the
value of the current bit , the password has a total of 4 digits, and each input range is a number from 0-9).
Select the setting item, enter the parameter configuration page and short press the up and down keys to switch
the setting item;
Select the setting item, short press to confirm or right click, the setting item gets the cursor to represent the
selection and enter the setting item;
Adjust the parameter value: After selecting the setting item, the up and down keys can change the value or
optional value; the left and right keys move the cursor in the parameter item;
Confirm the parameter value: After adjusting the parameter value, press the enter key to exit the current

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setting item.
Save parameter settings and restart: After setting the parameters, move the cursor to save and restart, then
short press the confirmation key to enter the confirmation save and restart state. Short press the confirmation key
(press other keys to exit the confirmation state) to save the parameters and restart the device.
Exit without saving parameters: move the cursor to exit, then short press the confirmation key to enter the
confirmation exit state, short press the confirmation key (press other keys to exit the confirmation state), and then
exit the parameter configuration interface without saving the parameters .
Among them, the data bit and stop bit cannot be set. After the DHCP mode is turned on, the local IP address,
gateway, and subnet mask cannot be configured and are only assigned by the router;
4.4.4. Screen Sleep
The device screen has a sleep function, which is off by default and can be set to on in the configuration
interface.
In any interface, when there is no button operation for 180 seconds, the screen will enter the sleep mode. At
this time, the interface displays Ebyte robot. Press any button can exit the sleep mode.
When the screen is in sleep mode, the running efficiency of device programs will be improved.
4.5 MODBUS parameter configuration
4.5.1. AO Register List
Register function
Register
address
Register
type
Number
Operate
Data Range/Remarks
Related
function code
Analog output
value
0x0000
Holding
register
12
RW
32-bit floating point
type, unit mA
R：0x03
W：0x10
Analog output
value
0x0064
Holding
register
6
RW
Analog channel output
quantity, 2-byte integer,
unit (uA)
R：0x03
W：0x10
AO output mode
0x0514
Holding
register
6
RW
AO channel output
range
0x0000: 0~20mA
0x0001: 4-20mA
R：0x03
W：0x06、0x10
AO power-on
output initial value
0x00C8
Holding
register
12
RW
Output engineering
quantity when the
analog channel is
powered on, a 4-byte
floating point number,
the default is 0
R 0x03
W 0x10

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4.5.2. Module related registers
4.5.3. Network related registers
Register function
Register
address
Register
type
Number
Operate
Data Range/Remarks
Related function
code
Module MAC
address
0x0898
Holding
register
3
R
Device MAC parameters
R：0x03
Local IP address
0x089B
Holding
register
2
RW
Default: 192.168.3.7
R：0x03
W：0x06、0x10
local port
0x089D
Holding
register
1
RW
1～65535, default: 502
R：0x03
W：0x06、0x10
Subnet mask
address
0x089E
Holding
register
2
RW
Default: 255.255.255.0
R：0x03
W：0x06、0x10
Gateway address
0x08A0
Holding
register
2
RW
Default: 192.168.3.1
R：0x03
W：0x06、0x10
DHCP mode
0x08A2
Holding
1
RW
0x0000 static IP
R：0x03
Register function
Register
address
Register
type
Number
Operate
Data Range/Remarks
Related function
code
Module address
0x07E8
Holding
register
1
RW
Modbus address,
1～247 configurable
addresses
R：0x03
W：0x06
Module model
0x07D0
Holding
register
12
R
Get the current model
R：0x03
Firmware version
0x07DC
Holding
register
1
R
Get firmware version
number
R：0x03
Module name
0x07DE
Holding
register
10
RW
Custom module name
R：0x03
W：0x10
Module restart
0x07EA
Holding
register
1
W
Write any value to
restart
W：0x06
Restore factory
parameters
0x07E9
Holding
register
1
W
Write random value to
restore factory
parameters
W：0x06
Serial baud rate
0x0834
Holding
register
1
RW
See baud rate code table,
Default is 9600
(0x0003)
R：0x03
W：0x06、0x10
Serial check digit
0x0836
Holding
register
1
RW
0x0000 no checksum
(default)
0x0001 odd parity
0x0002 even parity
R：0x03
W：0x06、0x10