Ebyte E821-RTU User manual

Chengdu Ebyte Electronic Technology Co.,Ltd E821-RTU (0400-ETH)User Manual
Copyright ©2012–2019, Chengdu Ebyte Electronic Technology Co.,Ltd
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Contents
Features...................................................................................................................................................................................3
1. Quick start...........................................................................................................................................................................4
1.1 Port Connection........................................................................................................................................................4
1.1.1 RS485 connection......................................................................................................................................... 4
1.1.2 Analog input connection............................................................................................................................... 4
1.2 Basic operation.........................................................................................................................................................5
1.2.1 RS485 Bus control........................................................................................................................................ 5
1.2.2 Ethernet control.............................................................................................................................................7
2. Product description............................................................................................................................................................. 9
2.1 Basic parameters...................................................................................................................................................... 9
2.2 Size and Interface description................................................................................................................................ 10
2.3 Reset button description......................................................................................................................................... 12
3. Modbus............................................................................................................................................................................. 13
3.1 Register Address Table...................................................................................................................................................13
3.2 Modbus address table..................................................................................................................................................... 14
3.3 RS485 serial port baud rate code value table..................................................................................................................14
3.4 RS485 serial port parity bit value table.......................................................................................................................... 14
3.5 Configure parameters by setting software...................................................................................................................... 15
4. Product Function...............................................................................................................................................................16
4.1 Working mode................................................................................................................................................................ 16
4.1.1 Slave mode..................................................................................................................................................16
4.1.2 Master mode................................................................................................................................................16
4.2 RTU basic function.........................................................................................................................................................17
4.2.1 Read analog-data AI input.......................................................................................................................... 17
4.2.2 Analog AI acquisition range setting........................................................................................................... 18
4.3 Network related functions...............................................................................................................................................18
4.3.1 Device MAC address reading..................................................................................................................... 18
4.3.2 Device SN code reading..............................................................................................................................19
4.3.3 Network function parameter validation command (Ethernet restart command)........................................ 19
4.3.4 WAN port IP info configuration................................................................................................................. 20
4.3.5 Set DNS...................................................................................................................................................... 20
4.3.6 Set network protocol parameters................................................................................................................ 21
4.3.7 Set the registration package mode.............................................................................................................. 22
4.3.8 Set the registration package contents..........................................................................................................22
4.3.9 Set heartbeat package mode........................................................................................................................23
4.3.10 Set heartbeat package content...................................................................................................................24
4.3.11 Set heartbeat package time........................................................................................................................24
4.3.12 Clear the cache..........................................................................................................................................25
4.3.13 Set keep-alive parameters......................................................................................................................... 25
4.3.14 Set local port number................................................................................................................................ 26
4.3.15 Set cloud transparent transmission function............................................................................................. 27
4.3.16 Set timeout restart time............................................................................................................................. 27

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Important Statement..............................................................................................................................................................28
Reversion History................................................................................................................................................................. 28
About Us...............................................................................................................................................................................28

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Features
Support 4 analog inputs, default current acquisition;
Support Ethernet port, you can use socket to connect to remote server, support TCP/UDP;
Support Modbus TCP/RTU protocol;
Support Ebyte Cloud, can be controlled by commands;
Support 2 working modes, master mode and slave mode, slave can cascade multiple devices by RS485;
Support Reload touch button, long press for 5s, Modbus device address, RS485 serial port baud rate and check digit
will restore factory settings;
Hardware watchdog with high reliability;
Multiple indicators to show device working status;
The power supply has static and surge level 3 protection, and has over-current, over-voltage, anti-reverse and other
protections.
Note: Support customization of functions, such as conditional control (how to output based on input state)

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1. Quick start
This chapter is a quick introduction to E821-RTU (0400-ETH). It is recommended that users carefully read this
chapter and follow the instructions before using the product. It will have a systematic understanding of the product, and
users can also choose the one you are interested in according to your needs. For specific details and instructions, please
refer to the following sections.
1.1 Port Connection
1.1.1 RS485 connection
The E821-RTU device has a master-slave mode and can be cascaded by the RS485 port.
Note: 120R (matching resistor) is added and not added according to the actual line matching (default is not added).
1.1.2 Analog input connection

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1.2 Basic operation
Connection: The computer connects to E821-RTU (0400-ETH) by USB to RS485 cable or the computer connects to
E821-RTU (0400-ETH) by Ethernet cable.
Power supply: E821-RTU (0400-ETH) working voltage is DC 8~28V, and the power supply has at least 0.2A power
supply capability.E821-RTU(0400-ETH).
1.2.1 RS485 Bus control
Select the device model, port number, set the baud rate check, and click “Search” to search for the device.
After searching for the actual connected device, click “Stop”; the number of connected devices in the example is 1.

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At this time, you can see the address of the current device, check "Auto Refresh" to perform analog input reading.
The example shows that channel 4 has 10mA current input.

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1.2.2 Ethernet control
Click the parameter setting and parameter reading, we can see that the device address is "1", in "slave mode", the
local IP is "192.168.4.101", the subnet mask is "255.255.255.0", the role is "TCP server", and the port number is 8666.
Click Local connection, set the computer IP: "192.168.4.10", subnet mask: "255.255.255.0", gateway: 192.168.4.1.

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Open the network debugging assistant, set the port number and other parameters, click the connection, you can find
that the device LINK light is on to indicate the connection is successful.
Send Modbus command: 01 03 00 10 00 04 45 CC, to read the current value collected by 4 analog channels.

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2. Product description
E821-RTU (0400-ETH) is a data acquisition product which supports four analog (current) inputs and supports
Modbus TCP/RTU protocol. The product is highly easy to use and can be easily and quickly integrated into your system
for remote network-based data acquisition.
2.1 Basic parameters
Item
Description
Network parameters
Ethernet Specification
RJ45, 10/100Mbps
Network Protocol
IP, TCP/UDP, ARP, ICMP, IPV4
IP acquisition method
Static IP, DHCP
DNS
Available
Hardware parameters
Size (H*W*D)
108*75*37mm
Weight
230.8±5g
Working temperature
-20℃~+70℃
Storage temperature
-40℃~+85℃
Working humidity
5%~95%
Storage humidity
1%~95%
Working voltage
8V~28V, 8V/143mA, 12V/98mA, 24V/52mA,
28V/45mA
Current acquisition range
0mA~20mA or 4mA-20mA
Accuracy
0.2%
Data interface
RS485: 1200~115200bps, RJ45: 100M
Software parameters
Network type
Ethernet
Configuration command
Modbus TCP/RTU
Network Protocol
Modbus TCP/RTU
Working mode
Master mode, Slave mode
Data transmission mode
TCP/UDP

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No
Item
Function
Description
1
RJ45
Ethernet
tandard RJ45 interface, connected to device or PC
2
DC-IN
DC JACK 5.5*2.1mm
Power input, DC 8V~28V, 12V/24V recommended
3
DC-IN +
Crimping terminal
power input positive
Power input, DC 8V~28V, 12V/24V recommended
4
DC-IN -
Crimping terminal
power input negative
Power Ground
5
RS485 G
RS485 ground
Signal ground, can not be connected
6
RS485 A
RS485 A
RS485 B is connected to device A
7
RS485 B
RS485 B
RS485 B is connected to device B
8
Grounding screw
Connecting to ground
Connecting to ground
9
Reset
Reset button
Long Press for 5S effective
10
AI1+
Analog signal input
channel 1 positive
Analog signal input channel, used in combination
with the negative to collect analog data
11
AI1-
Analog signal input
channel 1 negative
Analog signal input channel, used in combination
with the positive to collect analog data
12
AI2+
Analog signal input
channel 2 positive
Analog signal input channel, used in combination
with the negative to collect analog data
13
AI2-
Analog signal input
channel 2 negative
Analog signal input channel, used in combination
with the positive to collect analog data
14
AI3+
Analog signal input
channel 3 positive
Analog signal input channel, used in combination
with the negative to collect analog data
15
AI3-
Analog signal input
channel 3 negative
Analog signal input channel, used in combination
with the positive to collect analog data
16
AI4+
Analog signal input
channel 4 positive
Analog signal input channel, used in combination
with the negative to collect analog data

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17
AI4-
Analog signal input
channel 4 negative
Analog signal input channel, used in combination
with the positive to collect analog data
LED Indicator light
1
PWR
Power supply indication
Red after power on, long bright
2
NET
Ethernet connection
indication
Blue and green two-color LED, the blue LED is long
bright after the Ethernet port TCP/UDP connection is
successful. After power-on, the green LED is lit,
indicating that it is initializing.
3
DATA/RST
Data indication/reset
indication
Blue and green two-color LED, blue LED flashes
when data is transmitted and received, green LED
flashes 3 times after reset
Note: It is recommended to connect the case to the ground..
2.3 Reset button description
Long press for 5S is valid. After the reset is successful, the RST LED flashes 3 times, the Modbus device address,
RS485 serial port baud rate and parity bit are restored to the factory settings, other configuration parameters are
unchanged.

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3. Modbus
3.1 Register Address Table
Register Address Table (Function table: 0x03H, 0x04H, 0x06H, 0x10H)
Register
Address
Number
of
registers
Register properties
Register
type
Register
value range
Default value
Function
Code
30017 (0x0010)
1
AI4 Input value/uA
Read only
0-20000
-
0x03
0x04
30018 (0x0011)
1
AI3 Input value/uA
Read only
-
30019 (0x0012)
1
AI2 Input value/uA
Read only
-
30020 (0x0013)
1
AI1 Input value/uA
Read only
-
Reserve
40078
(0x004D)
1
Device address
Read/Write
1 - 247
01
0x03
0x06
40079
(0x004E)
1
Baud rate
Read/Write
0 - 7
03
40080 (0x004F)
1
Parity bit
Read/Write
0 - 2
00
40081(0x0050)
1
Master mode or
slave mode
Read/Write
0 - 1
01
Reserve
40084(0x0053)
1
Set Analog range
Read/Write
0 - 1
01
Reserve
40098 (0x0061)
3
Set MAC address
Read
-
-
0x03
0x06
0x10
40104 (0x0067)
1
Ethernet restart
Read/Write
-
-
40108
(0x006B)
7
WAN port IP info
Read/Write
-
Static
192.168.4.101
255.255.255.0
192.168.4.1
40122 (0x0079)
4
Set DNS info
Read/Write
-
61.139.2.69
192.168.4.1
40130 (0x0081)
4
Set Network protocol
parameters
Read/Write
-
TCPS,192.168.
4.10, 8886
40146 (0x0091)
1
Set registration
package mode
Read/Write
0-4
“0” Close the
registration
package
40150 (0x0095)
21
Set registration
package content
Read/Write
-
regist msg
40234
(0x00E9)
21
Set heartbeat
package content
Read/Write
-
heartbeat msg
40318
(0x013D)
1
Set heartbeat
package mode
Read/Write
0-1
“0” Network
heartbeat
package
40322 (0x0141)
1
Set heartbeat time
Read/Write
0、2-65535
0
40330 (0x0149)
1
Set clear cache
Read/Write
0-1
Do not clear
the cache data
of the
SOCKET A1
link
40336 (0x014F)
3
Set keep-alive
parameters
Read/Write
-
Detection time:
10s, Detection
interval: 5s,
Detection
times: 30

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40350
(0x015D)
1
Set local port
Read/Write
0-65535
8886
40354 (0x0161)
1
Set cloud
transmission
function
Read/Write
0-1
Close
40356 (0x0163)
1
Set timeout restart
time
Read/Write
60-65535
3600
40358 (0x0165)
4
SN code
Read
-
-
3.2 Modbus address table
Modbus address table
1 (default)
1
2
2
3
3
…
…
245
245
246
246
247
247
3.3 RS485 serial port baud rate code value table
Baud rate code value table
0
1200
1
2400
2
4800
3 (default)
9600
4
19200
5
38400
6
57600
7
115200
3.4 RS485 serial port parity bit value table
Parity bit value table
0 (default)
No parity
1
Even parity
2
Odd parity

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3.5 Configure parameters by setting software
Select the “Parameter Setting” column to read parameters and write parameters. For specific functions, please refer
to the product function description below.

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4. Product Function
4.1 Working mode
The working mode has master mode and slave mode, which are configured by Modbus register 40081 (0x0050).
When the register value is 0, it is the master mode; when the register value is 1, it is the slave mode, and default is the
slave mode.
4.1.1 Slave mode
In slave mode (register value is 0x01), the data sent to the device by network or 485 bus (sender) conforms to
Modbus RTU or Modbus TCP protocols, and the address in the data is the device address. The device will respond to the
sender with the same protocol. If the data sent to the device by the network end or 485 bus end does not conform to the
Modbus RTU or Modbus TCP protocol, or meets the Modbus RTU or Modbus TCP protocol, but the data address is
different from that of the device, the data will be discarded.
In the slave mode, the device can directly connect to the device in master mode through the 485 bus. When the slave
is not connected to the network, the network can also access the data of the slave through the master.
4.1.2 Master mode
In slave mode (register value is 0x00), the data sent to the device by network or 485 bus (sender) conforms to
Modbus RTU or Modbus TCP protocols, and the address in the data is the device address. The device will respond to the
sender with the same protocol. If the data sent to the device by the network end or 485 bus end does not conform to the
Modbus RTU or Modbus TCP protocol, or meets the Modbus RTU or Modbus TCP protocol, but the data address is
different from that of the device, the data of 485 bus will be transmitted to the network, and the data on the network will
be transmitted to 485 bus.
This function of host mode can realize the cascade function of devices and the data transmission between 485 bus
and network.

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4.2 RTU basic function
4.2.1 Read analog-data AI input
Function code: 03, Read hold-register; 04, Read input-register
Address range: 30017(0x0010)~30020(0x0013)
Remark: The unit of analog input value is uA
E.g.:
Function code 0x03, read AI1 input, assuming AI1 input is 9946uA, the corresponding value should be 0x26 DA
Modbus RTU protocol read analog-data input:
Send
01
03
00 13
00 01
75 CF
Device ModBus
address
Function
code
Analog-data start
address
Read the number of
addresses
CRC check code
Receive
01
03
02
26 DA
23 BF
Device ModBus
address
Function
code
Number of bytes
returned
Analog-data input
value
CRC check code
Modbus TCP protocol read analog-data input:
Send
00 01
00 00
00 06
01
03
00 13
00 01
Transmiss
ion
identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Analog-data start
address
Read the number
of addresses
Receive
00 01
00 00
00 05
01
03
02
26 DA
Transmiss
ion
identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Number of bytes
returned
Analog-data input
value

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Function code 0x04, read AI1 input, assuming AI1 input is 9946uA, the corresponding value should be 0x26 DA
Modbus RTU protocol read analog-data input:
Send
01
04
00 13
00 01
C0 0F
Device ModBus
address
Function
code
Analog-data start
address
Read the number of
addresses
CRC check code
Receive
01
04
02
26 DA
22 CB
Device ModBus
address
Function
code
Number of bytes
returned
Analog-data input
value
CRC check code
Modbus TCP protocol read analog-data input:
Send
00 01
00 00
00 06
01
04
00 13
00 01
Transmiss
ion
identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Analog-data start
address
Read the number
of addresses
Receive
00 01
00 00
00 05
01
04
02
26 DA
Transmiss
ion
identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Number of bytes
returned
Analog-data input
value
4.2.2 Analog AI acquisition range setting
When the value of register 0x40084 (0x0053) is 0, the analog input range is 0 - 20mA;
When the value of register 0x40084 (0x0053) is 1, the analog input range is 4 - 20mA;
Note: When the range is 4-20mA, the input current is <4mA, the register value will be 0.
4.3 Network related functions
4.3.1 Device MAC address reading
Modbus RTU protocol write register:
Send
01
03
00 61
00 03
54 15
Device ModBus
address
Function
code
Start address
Read number of
registers
CRC check code
Receive
01
03
06
1A 00 1C C0 BB FF
16 53
Device ModBus
address
Function
code
Number of
bytes
Read value
CRC check code
Modbus TCP protocol write register:
Send
00 01
00 00
00 06
01
03
00 61
00 03
Transmissio
Protocol
Length
Unit
Functio
Address
Write value

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n identifier
identifier
identifier
n code
Receive
00 01
00 00
00 09
01
03
06
1A 00 1C C0 BB
FF
Transmissio
n identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Number of bytes
Read value
Note: 1A 00 1C C0 BB FF is the MAC address of the device, the device has a unique MAC address.
4.3.2 Device SN code reading
Modbus RTU protocol read register:
Send
01
03
01 65
00 04
55 EA
Device ModBus
address
Function
code
Start address
Read number of
registers
CRC check code
Receive
01
03
08
19 05 21 14 00 13 55 50
F9 AA
Device ModBus
address
Function
code
Number of
bytes
Read value
CRC check code
Modbus TCP protocol read register:
Send
00 01
00 00
00 06
01
03
01 65
00 04
Transmissio
n identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Address
Read number
Receive
00 01
00 00
00 0B
01
03
08
19 05 21 14 00 13 55 50
Transmissio
n identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Number
of bytes
Read value
Note: 19 05 21 14 00 13 55 50 is the device SN code, the devices have different SN codes.
4.3.3 Network function parameter validation command (Ethernet restart command)
Modbus RTU protocol write register:
Send
01
06
00 67
00 01
F9 D5
Device ModBus
address
Function
code
Address
Write value
CRC check code
Receive
01
06
00 67
00 01
F9 D5
Device ModBus
address
Function
code
Address
Write value
CRC check code
Modbus TCP protocol write register:
Send
00 01
00 00
00 06
01
06
00 67
00 01
Transmission
identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Address
Write value
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