Ebyte E90-DTU User manual

Chengdu Ebyte Electronic Technology Co.,Ltd. E90-DTU(xxxSL42) User Manual
Copyright ©2012–2023，Chengdu Ebyte Electronic Technology Co.,Ltd.

Chengdu Ebyte Electronic Technology Co.,Ltd. E90-DTU(xxxSL42) User Manual
Copyright ©2012–2023，Chengdu Ebyte Electronic Technology Co.,Ltd.
1
Catalogs
Disclaimer and Copyright Notice..........................................................................................................................1
Ⅰ Products.................................................................................................................................................................. 2
1.1 Product Description..................................................................................................................................2
1.2 Features........................................................................................................................................................2
Ⅱ Quick Start............................................................................................................................................................4
Ⅲ Product Size..........................................................................................................................................................5
3.1 Interfaces and Indications....................................................................................................................6
Ⅳ Interface definitions........................................................................................................................................7
4.1 Power connector description..................................................................................................................7
4.2 RS232 Interface Definition....................................................................................................................7
4.3 RS485 Interface Definition....................................................................................................................7
Ⅴ Technical indicators..........................................................................................................................................7
5.1 Model Specification ..................................................................................................................................7
5.2 General Specification Parameters ....................................................................................................... 8
5.3 Frequency range and number of channels........................................................................................... 8
5.4 Transmit power level ................................................................................................................................9
5.5 Airspeed rating..........................................................................................................................................9
5.6 Current parameter ......................................................................................................................................9
5.7 Receiving and dispatching lengths and subcontracting modalities.........................................9
Ⅵ Functions in detail..........................................................................................................................................10
6.1 Fixed-point launch (hexadecimal) ..................................................................................................... 10
6.2 Broadcast transmissions (hexadecimal) ........................................................................................... 10
6.3 Broadcast address ....................................................................................................................................11
6.4 Listening address ....................................................................................................................................11
6.5 Exception Work Status Log Printing Details......................................................................... 11
Ⅶ Operating mode ....................................................................................................................................................12
7.1 General mode..............................................................................................................................................12
7.2 Configuration Mode..................................................................................................................................12
Ⅷ Register read/write control..........................................................................................................................13
8.1 Command format..........................................................................................................................................13
8.2 Register description..............................................................................................................................13
8.3 Factory Default Parameters..................................................................................................................17
Ⅸ Relay Networking Mode Usage..........................................................................................................................18
Ⅹ Configuration instructions for the host computer............................................................................... 19
Xl IAP Online Firmware Upgrade..........................................................................................................................20
XII Related Products..............................................................................................................................................22
XIII Practical application areas ......................................................................................................................24
XIV Precautions for use........................................................................................................................................25
Important statement ................................................................................................................................................26
Eevision history......................................................................................................................................................26
About us ...................................................................................................................................................................... 26

Chengdu Ebyte Electronic Technology Co.,Ltd. E90-DTU(xxxSL42) User Manual
Copyright ©2012–2023，Chengdu Ebyte Electronic Technology Co.,Ltd.
1
Disclaimer and Copyright Notice
The information in this document, including the URL addresses for reference, is
subject to change without notice. this document is provided "as is" without warranty
of any kind, including any warranty of merchantability, fitness for a particular
purpose, or non-infringement, and any warranty that any proposal, specification, or
sample is referred to elsewhere. This document is provided without warranty of any
kind, including any warranty of merchantability, fitness for a particular purpose or
non-infringement, and any warranty mentioned elsewhere in any proposal, specification
or sample. This document does not grant any license, express or implied, by estoppel
or otherwise, to use any intellectual property.
The test data in this article are all obtained from EBYTE laboratory tests, and
the actual results may vary slightly.
All trade names, trademarks and registered trademarks mentioned herein are the
property of their respective owners and are hereby acknowledged.
The final explanation right belongs to Chengdu Ebyte Electronic Technology
Co.,Ltd.
Notice
The contents of this manual are subject to change due to product version upgrade or other reasons. Chengdu
Ebyte Electronic Technology Co.,Ltd.reserves the right to make changes to the contents of this manual without
notice or prompting. Chengdu Ebyte Electronic Technology Co.,Ltd. makes every effort to provide accurate
information in this manual, however,Chengdu Ebyte Electronic Technology Co.,Ltd.does not warrant that the contents
of this manual are error-free, and all statements, information and recommendations in this manual do not constitute
any warranty, express or implied.

Chengdu Ebyte Electronic Technology Co.,Ltd. E90-DTU(xxxSL42) User Manual
Copyright ©2012–2023，Chengdu Ebyte Electronic Technology Co.,Ltd.
Ⅰ Products
1.1 Product Description
E90-DTU (xxxSL42) series is a real high-quality industrial-grade wireless
digital transmission radio (the radio won the national design patent
ZL202030009845.3), the radio adopts the LORA spread spectrum technology, its
strong anti-interference ability, so that the wireless communication in the
industrial field is more stable and reliable.
It has a variety of transmission modes, and the radio provides transparent
RS232/RS485 interfaces.LoRa direct-sequence spread spectrum technology will
bring a longer communication distance, and has the advantage of strong
anti-interference ability. The module has software FEC forward error correction algorithm, which has high coding
efficiency and strong error correction capability, and can actively correct the interfered data packets in case
of sudden interference, greatly improving reliability and transmission distance. In the absence of FEC, such
packets can only be discarded. The radio has data encryption function, the data transmitted by the radio in the
air, with randomness, through the strict encryption and decryption algorithms, which makes the data interception
lose its significance; it supports the sub-packet length setting, and supports different real-time and data
packets.
Wireless digital transmission radio as a communication medium, and optical fiber, microwave, open-wire, there
is a certain scope of application: it provides some special conditions under the special network of real-time
monitoring signals, reliable data transmission, has a low cost, easy to install and maintain, strong ability to
bypass the shot, the flexible network structure, the coverage of the characteristics of the range of long distance,
suitable for multi-point and dispersed locations, complex geographic environments and so on occasions, and can
be connected with the PLC, RTU, rain gauge, liquid level meter, and other data terminals.
1.2 Features
Ambient field strength dynamic indication, packet RSSI dynamic indication;
Hardware and software dual watchdog;
Transmission distance up to 30+ KM ideally;
Dust and moisture proof;
Easy-to-use product and upper computer configuration;
Adopting the latest LoRa technology, it has a longer distance and more powerful performance than traditional
LoRa digital radio;
Adopting the latest LoRa technology, it has a longer distance and more powerful performance than traditional
LoRa digital radio;
Single packet supports 32~240 bytes;
Simple and efficient power supply design with crimped wires, supporting 12V power supply;
Transmit power up to 15W;
Support LBT function, the radio automatically waits for transmitting according to the current environment
noise intensity. It greatly improves the communication success rate of the module in harsh environment;
supports communication key function, which effectively prevents data from being intercepted;

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can realize multi-level relay networking, effectively expanding the communication distance and realizing
ultra-long-distance communication;
adopts temperature compensated crystal, the frequency stability is better than ±1PPM;
Full aluminum alloy shell, compact size, easy installation, good heat dissipation; perfect shielding design,
good electromagnetic compatibility, strong anti-interference ability;
All parameters can be programmed: e.g. power, frequency, air rate, address ID etc;
Temperature monitoring, antenna anomaly monitoring, and at the same time with temperature overheating, antenna
anomaly protection function;.

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Ⅱ Quick Start
Note: When using this device must be external 50 ohm impedance antenna, at the
same time two devices and antennas must be spaced more than 6 meters apart to
use, otherwise there is a risk of damage to the device!!!!
You need to prepare E90-DTU (230SL42) radio, antenna, 12V/4A power supply, serial connection cable.
1、 first install the antenna to the digital radio, then install the power supply, only support the pressure
line method, at this time, the power light is on, no indication of abnormal light;
2、 Use USB to RS-232 or USB to RS-485 to connect your computer to the digital radio;
3、 start two serial port debugging assistant, select the serial port baud rate of 9600bps, the checksum method
is 8N1, you can realize the serial port transmission;
4、 If customers need to modify the parameters, please short the MOD pin to GND, enter the configuration mode,
open the E90-DTU SL digital radio configuration software, you can modify the relevant parameters, after
completing the configuration, please put the MOD pin to the empty state.

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Ⅲ Product Size

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3.1 Interfaces and Indications
foot
number
Name
Function
Description
1
GND
Crimped Power
Supply Input
Negative
Power Reference Ground
2
VCC
Positive input for
crimped power
supply
Power input (12V/4A)
3
MOD
Mode Control
Suspended, General Mode; Grounded,
Configuration Mode
4
RS485 G
RS485 interface G
RS485 interface G connected to the device GND
interface (recommended connection)
5
RS485 B
RS485 Interface B
RS485 interface B connected to device B
interface
6
RS485 A
RS485 Interface A
RS485 interface A connected to device A
interface
7
RS232
RS232 interface
Standard RS232 interface
8
ANT
SMA-K connector
External threaded bore, 10mm long,
characteristic impedance 50Ω
9
UPDATE
-
Hidden buttons so users don't have to care
10
PWR
Power indicator
Red, illuminated when power is on
11
TXD
Serial Data
Transmission
Indicator
Yellow, blinking when sending data

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12
RXD
Serial Data
Receiving
Indicator
Yellow, blinking when receiving data
13
ERR
warning indicator
Unconnected antenna or voltage, temperature
abnormalities, unconnected antenna
abnormalities resolved need to be re-powered
to work properly
Ⅳ Interface definitions
4.1 Power connector description
The user is powered by a pressurized wire, 12V/4A DC power supply.
4.2 RS232 Interface Definition
The E90-DTU can be connected to the device via RS232 using a standard DB9 interface.
4.3 RS485 Interface Definition
The E90-DTU can use RS485 interfaces A, B, and G to connect to RS485's A, B, and G of the device respectively.
Note: Poor communication occurs when connecting the radio to multiple devices, but not with a single device,
try connecting a 120Ω matching resistor in parallel between terminals 485_A and 485_B.
Ⅴ Technical indicators
5.1 Model Specification
Model
Specification
Operating
Frequency
Transmit
Power
Referenc
e
Distance
Specification
Characteristics
Recommended Scenarios
Hz
W
km

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E90-DTU(230SL42)
230M
15
30
LoRa spread
spectrum
anti-interferenc
e
Suitable for long distances and
interference-prone environments
E90-DTU(400SL42)
433.125M
15
30
LoRa spread
spectrum
anti-interferenc
e
Suitable for long distances and
interference-prone environments
Note: Sunny weather, open environment without obstruction, 12V/4A power supply, 6dBi fiberglass antenna,
antenna height 2 meters from the ground, use factory default parameters.
5.2 General Specification Parameters
Sserial
Number
Name
Specification
Instruction
1
Product Size
124*109.0*35.2mm
See mounting dimensions for details
2
Product weight
425g
Weight tolerance 5g
3
operating
temperature
-40℃～+85℃
Meet the demands of industrial-grade use
4
Antenna
Impedance
50Ω
Standard 50Ω characteristic impedance
5
voltage range
12±1V DC
Recommended to support instantaneous current 4A
6
communication
interface
RS232/RS485
Standard DB9 hole type/5.08 terminal block
7
baud rate
Factory default 9600
Baud rate range 1200 to 115200
8
address code
Factory default 0
Total 65536 address codes can be set
5.3 Frequency range and number of channels
Model Specification
Default
frequency
Frequency range
Channel
spacing
Number of channels
Hz
Hz
Hz
E90-DTU(230SL42)
230M
225～236M
0.25M
45, half-duplex
E90-DTU(400SL42)
433.125M
410.125～493.125M
1M
84, half-duplex
NOTE: When using multiple sets of digital transmission radios to communicate one-to-one at the same time
in the same area, it is recommended that each set of digital transmission radios be set up with a channel
interval of 2 MHz or more.

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5.4 Transmit power level
Model Specification
10/15W
E90-DTU(230SL42)
Software adjustable, default 15W
E90-DTU(400SL42)
Software adjustable, default 15W
5.5 Airspeed rating
Model Specification
Default Air
Rate
Level
Airspeed rating
bps
kbps
E90-DTU(230SL42)
2.4k
7
0.3、0.6、1.2、2.4、4.8、9.6、15.6、
E90-DTU(400SL42)
2.4k
8
0.3、1.2、2.4、4.8、9.6、19.2、38.4、62.5
Note: The higher the air rate setting, the faster the transmission rate and the closer the transmission distance;
therefore, it is recommended that the air rate be as low as possible if the rate meets the usage requirements.
5.6 Current parameter
Model Specification
Supply voltage (V)
Emission current (A)
Guard current (mA)
E90-DTU(230SL42)
12±1
2.5~3.5
45
E90-DTU(400SL42)
12±1
2.5~3.5
45
Note: It is recommended to keep more than 50% current margin when selecting the power supply, which is conducive
to the long-term and stable operation of the radio, Below or exceeding the power supply range of the device
may trigger the internal protection of the device can not work, please ensure the stability of the power
supply voltage when using.
5.7 Receiving and dispatching lengths and subcontracting modalities
Model Specification
Cache size
Subcontracting
E90-DTU(230SL42)
1000 bytes
Command-set packetized 32/64/128/240 byte
transmissions
E90-DTU(400SL42)
1000 bytes
Command-set packetized 32/64/128/240 byte

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transmissions
Note: 1. If the radio's single received data is larger than the single packet capacity, the exceeding part
of the data will be automatically assigned to the second transmission until the transmission is completed;
2、Radio station's single reception data can not be larger than the cache capacity.
Ⅵ Functions in detail
6.1 Fixed-point launch (hexadecimal)
For fixed-point transmission, the module recognizes the first three bytes of the received serial data
as:
Address High + Address Low + Channel and uses it as the wireless transmit target.
6.2 Broadcast transmissions
(hexadecimal)

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6.3 Broadcast address
Example: set module A address to 0xFFFF and channel to 0x04.
When module A is used as a transmitter (same mode, transparent transmission method), all receiving modules
under channel 0x04 can receive the data for the purpose of broadcasting.
6.4 Listening address
Example: set module A address to 0xFFFF and channel to 0x04.
When module A acts as a receiver, it can receive all the data under channel 0x04 for listening purpose.
6.5 Exception Work Status Log Printing Details
1. The ERR indicator blinks according to the following table based on the specific abnormal operating status.
Abnormal working
condition
Thresholds for determining
anomalous states
ERR indicator blinking condition
undervoltage
Supply voltage <11V
Blinks once in 500ms
overvoltage
Supply voltage >13V
1s blinks once
overheat
Module temperature > 120°C
2s blinks once
Overvoltage and
overheating
Supply voltage >13V and module
temperature >120°C
Ever Bright
unplugged antenna
Send without antenna
Ever Bright
2. The module will temporarily turn off the RF transmitting function under abnormal working condition until it
returns to normal working condition, then it will restart to turn on the transmitting.

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3. The module will carry out cyclic log printing (can be turned on/off) every 500ms in the abnormal state to inform
the user of the current abnormal working state, and the format of the print log is shown in the following table:
Note: Exception log printing enable bit (bit2 of instruction register 04H) 0: off 1: on Default is 0 (off)
Ⅶ Operating mode
E90-DTU has two working modes, MOD pin is suspended, general mode, i.e. the radio communicates normally; MOD
pin is grounded, configuration mode.
Type
Notes
General mode
Serial on, wireless on, transparent transmission (factory default mode)
Configuration
Mode
The user can access the registers through the serial port to control the working state
of the radio, and the user can configure the module through the upper computer configuration
software.
7.1 General mode
Type
Module operates in general mode (MOD pin suspended state)
Transmit
The user can enter data through the serial port and the module will initiate wireless
transmission.
Receive
The module's wireless reception function is turned on, and wireless data will be output
via the serial port pins when received.
7.2 Configuration Mode
Type
Module operating in configuration mode (MOD pin ground state)
Transmit
Wireless transmitter shutdown
Receive
Wireless reception off
Configuration
User access to registers to configure module operating parameters
Abnormal working condition
Print Log Format
undervoltage
Under Voltage!!!
overvoltage
Over Voltage!!!
过 overheat
Over Temperature!!!
Overvoltage and overheating
Over Voltage & Over Temperature!!!
unplugged antenna
WARNING!!!: No antenna

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Ⅷ Register read/write control
8.1 Command format
The list of supported commands in the configuration mode is as follows (only 9600, 8N1 format is supported at
the time of setup):
Seria
l
Numbe
r
Command format
Explanation
1
Setup Registers
Instruction: C0 + start address + length + parameters
Response: C1 + start address + length + parameters
Example 1: Configure the channel as 0x09
Command Start address Length Parameters
Send: C0 05 01 09
Return: C1 05 01 09
Example 2: Configure module address (0x1234), network address (0x00), serial port
(9600 8N1) and airspeed (1.2K) at the same time
Send: C0 00 04 12 34 00 61
Return: C1 00 04 12 34 00 61
2
Read registers
Command: C1 + start address + length
Response: C1 + start address + length + parameters
Example 1: Read channel
Command Start address Length Parameters
Send: C1 05 01
Return: C1 05 01 09
Example 2: Read module address, network address, serial port, airspeed at the same
time
Send: C1 00 04
Return: C1 00 04 12 34 00 61
3
Formatting
error
Format Error Response
FF FF FF FF
8.2 Register description
Address
Read/W
rite
Name
Descriptions
Remarks
00H
Read/W
rite
ADDH
ADDH (default 0)
Module address
high byte and low
byte. Note: When
the module
address is equal
01H
Read/W
rite
ADDL
ADDL（default 0）

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to FFFF, it can be
used as a
broadcast and
listen address,
i.e.: the module
will not be
address filtered
in this case1
02H
Read/W
rite
NETID
NETID（default 0）
Network address
for
distinguishing
networks. It
should be set to
the same when
communicating
with each other.
03H
Read/W
rite
REG0
7
6
5
UART serial port rate (bps)
Two modules
communicating
with each other
can have different
serial port baud
rates. The
checksums can also
be different.
When transmitting
larger data
packets
continuously,
users need to
consider data
blocking and even
possible loss due
to the same baud
rate. It is
generally
recommended that
the baud rates of
both sides of the
communication are
the same.
0
0
0
Serial port baud rate of 1200
0
0
1
Serial port baud rate of 2400
0
1
0
Serial port baud rate of 4800
0
1
1
Serial port baud rate of 9600（default）
1
0
0
Serial port baud rate of 19200
1
0
1
Serial port baud rate of 38400
1
1
0
Serial port baud rate of 57600
1
1
1
Serial port baud rate of 115200
4
3
serial port parity bit
0
0
8N1（default）
0
1
8O1
1
0
8E1
1
1
8N1（Equivalent to 00）
2
1
0
Wireless air rate (bps)
Both sides of the
communication
must be the same.
The higher the
rate, the lower
the delay and the
shorter the
distance.
E90-DTU(230SL42)
E90-DTU(400SL42)
0
0
0
Air rate 0.3k
Air rate 0.3k
0
0
1
Air rate 0.6k
Air rate 1.2k
0
1
0
Air rate 1.2k
Air rate 2.4k
(default)
0
1
1
Air rate 2.4k
Air rate 4.8k

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（default）
1
0
0
Air rate 4.8k
Air rate 9.6k
1
0
1
Air rate 9.6k
Air rate 19.2k
1
1
0
Air rate 15.6k
Air rate 38.4k
1
1
1
Air rate 15.6k
Air rate 62.5k
04H
Read/W
rite
REG1
7
6
Subcontracting Settings
The user sends
data less than the
packet length, the
output of the
serial port at the
receiving end is
presented as
uninterrupted
continuous
output.
The user sends
data larger than
the packet length,
the serial port at
the receiving end
will output in
packets.
0
0
240 bytes (default)
0
1
128 bytes
1
0
64 bytes
1
1
32 bytes
5
RSSI Ambient Noise Enable
When enabled, the
register can be
read by sending
command C0 C1 C2 C3
command in
transmission
mode.
register 0x00 ：
current ambient
noise RSSI
Register 0X01 :
RSSI of last
received data.
(Current channel
noise is: dBm
=-(256-RSSI))
Instruction
format: C0 C1 C2 C3
+ start address +
read length
return: C1 +
address address +
read length + read
the effective
value; such as:
send C0 C1 C2 C3 00
01
return C1 00 01
RSSI (address can
only start from
00)
0
Disable (default)
1
enable
4
3
reserve
2
Abnormal operation status log printing enable
According to the
different abnormal
0
Disable (default)

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working status to print
the corresponding
different format log,
for details, see
section 6.5, abnormal
working status log
printing details.
1
enable
1
0
firing power
Power and current
are nonlinearly
related, and the
power supply is
most efficient at
maximum power.
Current does not
decrease
proportionally
with power
reduction
0
0
41.5±0.5dBm (default)
0
1
1
0
1
1
40dBm
05H
Read/W
rite
REG2
Channel Control (CH)
0-83 represent a total of 84 channels respectively
E90-DTU(400SL42)
0~44 represent a total of 45 channels respectively
E90-DTU(230SL42)
Actual frequency =
410.125 + CH*1.0M
Actual Frequency =
225 + CH*0.25M
06H
Read/W
rite
REG3
7
Enable RSSI bytes
When enabled, the
module receives
wireless data,
which will follow
an RSSI intensity
byte when output
through the serial
port TXD.
0
Disable (default)
1
enable
6
transmission method
The module will
recognize the
first three bytes
of the serial port
data as: address
high + address low
+ channel, and
will use it as the
wireless transmit
target.
0
Transparent transmission (default)
1
fixed-point transmission
5
relay function
When the relay
function is
enabled, the
module will
initiate a
forwarding if the
destination
address is not the
module itself.
In order to
prevent data
backhauling, it is
recommended to use
it in conjunction
with fixed-point
0
Disable trunking (default)
1
Enable relay function

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mode. That is, the
destination
address is
different from the
source address.
4
LBT Enable
When enabled,
wireless data will
be listened to
before
transmitting,
which can avoid
interference to a
certain extent,
but may bring data
delays
The LBT has a
maximum dwell time
of 2 seconds and
will be forced to
issue when it
reaches two
seconds.
0
Disable (default)
1
enable
3
reserve
2
1
0
reserve
07H
Write
CRYPT_H
Key high byte (default 0)
Write only, read
returns 0
Used for user
encryption to
avoid
interception of
over-the-air
wireless data by
similar modules.
These two bytes
will be used
internally by the
module as a
computational
factor to
transform the
encryption of the
over-the-air
wireless signal.
08H
Write
CRYPT_L
Key low byte (default 0)
80H~
86H
Read
PID
7 bytes of product information
7 bytes of product
information
8.3 Factory Default Parameters
Model
E90-DTU(230SL42) factory default parameter value: 00 00 00 63 00 17 03 00 00 00
E90-DTU(400SL42) factory default parameter value: 00 00 00 62 00 17 03 00 00
Module
Model
frequency
address
signal
path
airspeed
baud rate
Serial
Port
Format
firing power

Chengdu Ebyte Electronic Technology Co.,Ltd. E90-DTU(xxxSL42) User Manual
Copyright ©2012–2023，Chengdu Ebyte Electronic Technology Co.,Ltd.
18
E90-DTU
(230SL42)
230MHz
0x0000
0x17
2.4kbps
9600
8N1
41.5±0.5dBm
E90-DTU
(400SL42)
433.125MHz
0x0000
0x17
2.4kbps
9600
8N1
41.5±0.5dBm
Ⅸ Relay Networking Mode Usage
serial
number
Description of trunking mode
1
After setting the relay mode by configuration, switch to the general mode and the relay starts
to work.
2
In repeater mode ADDH,ADDL are no longer used as module address, but correspond to NETID to forward
pairing respectively, and if one of the networks is received, it will be forwarded to the other
network. The repeater's own network ID is invalid.
3
In relay mode, the relay module serial port cannot send and receive data for low-power operation.
Trunking Networking Rules Description:
1、forwarding rules, relay can forward data in both directions between two NETIDs.
2、In relay mode, ADDH\ADDL is no longer used as the module address, as NETID forwarding pair.
3、In relay mode, the data sent should not exceed the set single packet packetization byte
As pictured:
1first-rate relay
"Node 1" NETID is 08.
"Node 2" NETID is 33.
The ADDH\ADDL of Relay 1 is 08, 33 respectively.
So the signal sent by node 1 (08) can be forwarded to node 2 (33)
Also node 1 and node 2 have the same address, so the data sent by node 1 can be received by node 2.
2Secondary Relay
The ADDH\ADDL of Relay 2 is 33, 05 respectively.
So relay 2 can forward relay 1 data to network NETID: 05.
Thus node 3 and node 4 can receive node 1 data. Node 4 outputs data normally, node 3 has a different address
from node 1, so it does not output data.
3bidirectional relay
As configured in the figure: the data sent by node 1 can be received by nodes 2 and 4, and the data sent by
nodes 2 and 4 can be received by node 1.