Ebyte E31-433T27D User manual

Chengdu Ebyte Electronic Technology Co.,Ltd. E31-433T27D User Manual
E31-433T27D User Manual
AX5243 433MHz 500mW DIP Wireless Module

Chengdu Ebyte Electronic Technology Co.,Ltd. E31-433T27D User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
1
Contents
1. Overview.............................................................................................................................................................................2
1.1 Introduction...............................................................................................................................................................2
1.2 Features.....................................................................................................................................................................2
1.3 Application................................................................................................................................................................2
2. Specifications......................................................................................................................................................................3
2.1 Limit parameters....................................................................................................................................................... 3
2.2 Working parameters..................................................................................................................................................3
3. Size and pin definition........................................................................................................................................................ 4
4. Connect to MCU.................................................................................................................................................................6
5 .Function description........................................................................................................................................................... 7
5.1 Fixed transmission.................................................................................................................................................... 7
5.2 Broadcasting transmission........................................................................................................................................ 7
5.3 Broadcasting address................................................................................................................................................ 8
5.4 Monitor address........................................................................................................................................................ 8
5.5 Reset..........................................................................................................................................................................8
5.6 AUX description....................................................................................................................................................... 8
5.6.1 Indication of UART output............................................................................................................................8
5.6.2 Indication of wireless transmitting................................................................................................................ 9
5.6.3 Configuration procedure of module...............................................................................................................9
5.6.4 Notes for AUX...............................................................................................................................................9
6. Operating mode.................................................................................................................................................................11
6.1 Mode switching.......................................................................................................................................................11
6.2 Normal mode（Mode 0）...................................................................................................................................... 12
6.3 WOR mode（Mode 1）.........................................................................................................................................12
6.4 Power saving mode（Mode 2）.............................................................................................................................12
6.5 Sleep mode（Mode 3）......................................................................................................................................... 13
7. Command format.............................................................................................................................................................. 14
7.1 Factory default parameter....................................................................................................................................... 14
7.2 Working parameter reading.................................................................................................................................... 14
7.3 Version number reading..........................................................................................................................................14
7.4 Reset instruction..................................................................................................................................................... 15
7.5 Parameter setting instruction.................................................................................................................................. 15
8. Hardware design............................................................................................................................................................... 17
9. FAQ.................................................................................................................................................................................. 18
9.1 Transmission distance is not ideal.......................................................................................................................... 18
9.2Module is easy to damage........................................................................................................................................18
9.3 Bit error rate is too high..........................................................................................................................................18
10. Welding operation guidance........................................................................................................................................... 19
11. Related Products............................................................................................................................................................. 20
12. Antenna Instruction.........................................................................................................................................................21
13. Batch packaging method.................................................................................................................................................22
Revise history....................................................................................................................................................................... 23
About us................................................................................................................................................................................23

Chengdu Ebyte Electronic Technology Co.,Ltd. E31-433T27D User Manual
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1. Overview
1.1 Introduction
E31-433T27D is a 433M DIP wireless serial port module
(UART) with AXSEM AX5243 RF chip imported from
Switzerland, half duplex, transceiver integrated, transparent
transmission mode,425~450.5MHz frequency band (default
433MHz), TTL level output with air wake-up function (ultra low
power consumption).
The module has a FEC forward error correction algorithm,
which has high coding efficiency and strong error correction
capability. In the case of sudden interference, it can actively
correct the interfered data packets, greatly improving reliability and transmission distance. In the absence of FEC, such
packets can only be discarded. The module has data encryption and compression function. The data transmitted by the
module in the air is random, and the data interception is meaningless through strict encryption and decryption algorithms.
The data compression function has the probability of reducing the transmission time, reducing the probability of
interference, improving reliability and transmission efficiency.
E31-433T27D strictly abides by FCC, CE and other domestic and foreign design specifications, meets all RF related
certifications, and meets export requirements.
1.2 Features
The real testing distance reaches 4km;
The max transmitting power is 500mW, multi-level is adjustable via the software;
Support global license-free ISM 433MHz band;
Support data transmission rate from 1.2kbps to 70kbps;
Support low power mode, suitable for battery applications;
Supports 3.3V~5.2V power supply, and more than 3.3V power supply can guarantee the best performance;
Support advanced ultra-narrow band GFSK modulation.
Industrial grade standard design, support for long-term use from -40 to 85 °C;
SMA interface, easy connection of coaxial cable or external antenna.
1.3 Application
Home security alarm and remote keyless entry;
smart home and industrial sensors;
wireless alarm security system;
Building automation solutions;
Wireless industrial grade remote control;
Intelligent agriculture and oilfield solutions;
health care products;
Advanced Meter Reading Architecture (AMI);
Automotive industry applications.

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2. Specifications
2.1 Limit parameters
Main parameter
Performance
Remark
Mini. value
Max. value
Supply voltage（V）
0
5.2
The module will be burnout
permanently with over 5.2V
Blocking power（dBm）
-
10
There’s small probability of burning
module at close range use
Operating temperature（℃）
-40
85
2.2 Working parameters
Main parameter
Performance
Remark
Mini.
value
Typical value
Max.
value
Supply voltage（V）
3.3
5.0
5.2
≥5.0V ensures output power
Communication level（V）
-
3.3
-
For 5V TTL, it may be at risk of
burning down
Operating temperature（℃）
-40
-
85
Industrial design
Working frequency（MHz）
425
-
450.5
Support ISM band
Power
consumption
Transmit current(mA）
-
380
Instant power consumption
Receive current（mA）
-
13
-
-
Sleep current（μA）
-
5
Software is shut down
Max. transmit power（dBm）
26.6
27.0
28.4
-
Receiving sensitivity（dBm）
-125
-126
-127
Air data rate is 1.3kbps
Air data rate（bps）
1.2k
5k
70k
Controlled via user’s programming
Main parameter
Description
Remark
Distance for reference
4000m
Test condition：clear and open area, antenna gain: 5dBi，
antenna height: 2.5m，air data rate: 1.3kbps
subcontracting method
43 Byte
The max capacity for each packet
Buffer
512 Byte
-
Modulation
GFSK
-
Communication interface
TTL
@3.3V
Package
DIP
-
Connector
2.54mm
-
Size
24*43mm
-
Antenna
SMA-K
50 ohm impedance

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3. Size and pin definition

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No.
Name
Direction
Function
1
M0
Input
（Weak pull-up）
Work with M1 to decide 4 working modes of module (not suspended, if
not used, could be grounded).
2
M1
Input
（weak pull-up）
Work with M0 to decide 4 working modes of module (not suspended, if
not used, could be grounded).
3
RXD
Input
TTL UART inputs, connects to external (MCU, PC) TXD output pin. Can
be configured as open-drain or pull-up input.
4
TXD
Output
TTL UART outputs, connects to external RXD (MCU, PC) input pin. Can
be configured as open-drain or push-pull output
5
AUX
Output
To indicate module ’ s working status & wakes up the external MCU.
During the procedure of self-check initialization, the pin outputs low
level. Can be configured as push-pull output (suspending is allowed).
6
VCC
Input
Power supply ：2.8~ 5.5V DC
7
GND
Input
Ground
8
Fixed orifice
-
Fixed orifice
9
Fixed orifice
-
Fixed orifice
10
Fixed orifice
-
Fixed orifice
11
Fixed orifice
-
Fixed orifice

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4. Connect to MCU
No.
Description（STM8L MCU）
1
The UART module is TTL level，pls connect to the MCU of TTL..
2
For some MCU works at 5VDC, it may need to add 4-10K pull-up resistor for the TXD & AUX pin.

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5 .Function description
5.1 Fixed transmission
5.2 Broadcasting transmission

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5.3 Broadcasting address
For example: Set the address of module A as 0xFFFF or 0x0000, and the channel as 0x04;
When module A works as transmitter(same mode, transparent transmission), all the receivers with 0x04 channel can
receive the data, to realize the broadcast transmission.
5.4 Monitor address
For example: Set the address of module A as 0xFFFF or 0x0000, and the channel as 0x04;
When module A is the receiver, it can receive the data sent from all modules under channel 0x04, the purpose of
monitor is realized.
5.5 Reset
When the module is powered, AUX outputs low level immediately, conducts hardware self-check and sets the
operating mode based on user’s parameters. During the process, the AUX remains low level. After the process
completed, the AUX outputs high level and starts to work as per the operating mode combined by M1 and M0.
Therefore, users need to wait the AUX rising edge as the start of module’s normal work.
5.6 AUX description
AUX Pin can be used as indication for wireless send & receive buffer and self-check.
It can indicate whether there are data that are not sent yet via wireless way, or whether all wireless data has been
sent through UART, or whether the module is still in the process of self-check initialization.
5.6.1 Indication of UART output
To wake up external MCU

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5.6.2 Indication of wireless transmitting
Buffer (empty): the internal 512 bytes data in the buffer are written to the RFIC (Auto sub-packaging).
When AUX=1, the user can input data less than 512 bytes continuously without overflow. Buffer (not empty): when
AUX=0, the internal 512 bytes data in the buffer have not been written to the RFIC completely. If the user starts to
transmit data at this circumstance, it may cause overtime when the module is waiting for the user data, or
transmitting wireless sub package.
When AUX = 1, it does not mean that all the UART data of the module have been transmitted already, perhaps the
last packet of data is still in transmission.
5.6.3 Configuration procedure of module
Only happened when Reset and exit sleep mode
5.6.4 Notes for AUX
For function 1 & function 2 mentioned above, the priority should be given to the one with low level output, which
means if it meets each of any low level output condition, AUX outputs low level, if none of the low level condition
is met, AUX outputs high level.
When AUX outputs low level, it means the module is busy & cannot conduct operating mode checking. Within 1ms
since AUX outputs high level, the mode switch will be completed.
After switching to new operating mode, it will not work in the new mode immediately until AUX rising edge lasts
for 2ms . If AUX stays on the high level, the operating mode switch can be affected immediately.

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When the user switches to other operating modes from mode 3 (sleep mode) or it’s still in reset process, the module
will reset user parameters, during which AUX outputs low level.

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6. Operating mode
There are four operating modes, which are set by M1 and M0, the details are as follows:
Mode（0-3）
M0
M1
Description
Remark
0 Normal mode
0
0
UART and wireless channel are open, transparent
transmission is on
The receiver must be Mode
0、1
1 WOR mode
1
0
UART and wireless channel are open；
The only difference with Mode 0: Before the data
packet transmitting, it will add wake-up code
automatically, in which the modules under mode 2
can be wake up.
The receiver can be mode0, 1,
or 2
2 Power saving mode
0
1
UART receiving is closed, wireless channel is under
WOR mode, after the wireless data is received, the
wireless channel will be open and send the data out.
The transmitter must be mode
1. In this mode, the
transmission is unavailable.
3 Sleep mode
1
1
The module enters sleep mode, but the parameters
can be configured.
See more details in working
parameters.
6.1 Mode switching
Users can combine M1 and M0 with high and low levels to determine the operating mode. Two GPIOs of the MCU
can be used to control mode switching; After changing M1 and M0: If the module is idle, after 1ms, it can start
working according to the new mode; If the serial port data of the module has not been transmitted through the
wireless, the new working mode can be switched after the transmission is completed; If the module receives the
wireless data and transmits the data through the serial port, it needs to finish transmission before switching the new
working mode; Therefore, mode switching can only be valid when AUX output is 1, otherwise it will delay
switching.
For example, in mode 0 or mode 1, users continuously inputs a large amount of data and simultaneously performs
mode switching. At this time, the switching mode operation is invalid; the module will process all the user data
before performing the new mode detection; Therefore, the general recommendation is to detect the output state of
the AUX pin and switch after 2ms when the output is high.
When the module is switched from other modes to sleep mode, if the data has not been processed yet; The module
will process these data (including receiving and sending) before entering sleep mode. This feature can be used for
fast sleep, which saves power; for example, the transmitter module works in mode 0, the user transmits the serial
port data "12345", and then does not have to wait for the AUX pin to be idle (high level), and can directly switch to
sleep mode. And the user's main MCU immediately sleeps, the module will automatically transmit the user data
through the wireless, and automatically enters sleep within 1ms; This saves MCU's working time and reduces power
consumption.
Similarly, any mode switching can use this feature. After the module processes the current mode event, it will
automatically enter the new mode within 1ms; thus eliminating the need for the user to query AUX and achieve the
purpose of fast switching; For example, switching from the transmit mode to the receive mode; the user MCU can
also enter sleep before the mode switch, and use the external interrupt function to acquire the AUX change, thereby
performing mode switching.
This operation mode is very flexible and efficient, and is designed according to the user's MCU's operation
convenience, and can reduce the workload of the entire system as much as possible, improve system efficiency, and
reduce power consumption.

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6.2 Normal mode（Mode 0）
Type
When M0 = 0，M1 = 0，the module works on Mode 0
Transmitting
The module receives the users’ data of serial port, and transmit 58 bytes wireless data packet. When the
input data packet reaches 58 bytes, the module will start the wireless transmission, thus users can
continue to input the transmitting data; When the input data packet is less than 58 bytes, the module will
wait 3 bytes time, if there’s no more data packet input, it means the data input finished, so the module
will send all data packet out via wireless; After the module receives the first data packet, the AUX
outputs low level; When module put all data into RF chip and start the transmission, the AUX outputs
high level; At this time, it means the last data packet starts wireless transmission, users can continue to
input 512 bytes data at most; The data packet sent in Mode 0 can be only received by the module with
Mode 0 and Mode 1.
Receiving
The module always open the wireless receiving function on, then it can receive the data packet sent by
Mode 0 and Mode 1.
After receiving the data packet, the AUX of module outputs low level and after delaying 5ms, the
wireless data will be transmitted via TXD pins of serial port. After all wireless data is transmitted via
serial port, the AUX outputs high level.
6.3 WOR mode（Mode 1）
Type
When M0 = 1，M1 = 0，the module works on Mode 1
Transmitting
The condition of module starting data packet transmission and the AUX function equal to Mode 0. The
only difference is that module will add wake-up code automatically before each data packet. The length
of wake-up code depends on the wake-up time set by users, the purpose of wake-up code is to wake up
the module with Mode 2; So, the transmitting data in Mode 1 can be received by the module with Mode
0, 1, 2.
Receiving
It equals to Mode 0.
6.4 Power saving mode（Mode 2）
Type
When M0 = 0，M1 = 1，the module works on Mode 2
Transmitting
The module is on sleep mode, serial port is close, so it cannot receive the serial port data of external
MCU. Thus, this module does not feature wireless transmitting function.
Receiving
In mode 2, the transmitter must be work in Mode 1; Monitoring the wake-up code at regular time, once a
valid wake-up code is received, the module continue to receive and wait for the entire valid data packet
to be received; Then AUX outputs low level, after delaying 5ms, the serial port is open and the received
wireless data will be transmitted via TXD, after that, AUX outputs high level; Wireless module continue
to enter “Sleep-Monitor”working mode(polling); Set different wake-up time, the module has different
receiving response time (max 2s) and different average power consumption(min 30uA); Users need to
strike a balance between communication latency and average power consumption.

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6.5 Sleep mode（Mode 3）
Type
When M0 = 1，M1 = 1，the module works on Mode 3
Transmitting
Transmitting the wireless data is unavailable.
Receiving
Receiving the wireless data is unavailable.
Configuration
Sleep mode can be used for module parameter setting. Use serial port 9600, 8N1 to set module working
parameters via specific command format.
Note
When entering other modes from the sleep mode, the module will reconfigure the parameters. During
the configuration process, AUX keeps low level; after that, AUX outputs high level, so it is
recommended that the user detect the AUX rising edge.

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7. Command format
In sleep mode (mode 3: M0 = 1, M1 = 1), the list of supported commands are as follows (only 9600, 8N1 format is
supported when)：
No.
Command format
Description
1
C0+Working parameters
The C0+5 byte working parameter is sent in hexadecimal format, 6 bytes in all, and
must be sent continuously (power-down save)
2
C1+C1+C1
Three C1s are sent in hexadecimal format. The module returns the saved parameters
and must be sent continuously.
3
C2+Working parameters
Send C2+5 byte working parameters in hexadecimal format, 6 bytes in all, must be
sent continuously (power off without saving)
4
C3+C3+C3
Three C3s are sent in hexadecimal format. The module returns version information and
must be sent continuously.
5
C4+C4+C4
Three C4s are sent in hexadecimal format, and the module will generate a reset and
must be sent continuously.
7.1 Factory default parameter
Model
Factory default parameter value：C0 00 00 18 50 44
Module Model
Frequency
Address
Channel
Air data rate
Baud Rate
Serial port format
Transmitting
power
E31-433T27D
433MHz
0x0000
0x50
1.2kbps
9600
8N1
500mW
7.2 Working parameter reading
Instruction format
Detailed description
C1+C1+C1
In sleep mode (M0=1, M1=1), a command (HEX format) is issued to the module serial port: C1
C1 C1, the module will return the current configuration parameters, such as: C0 00 00 1A 17
44.
7.3 Version number reading
Instruction format
Detailed description
C3+C3+C3
In sleep mode (M0=1, M1=1), a command (HEX format) is issued to the module serial port: C3
C3 C3, the module will return the current configuration parameters, such as: C3 32 xx yy;the
second byte represents the frequency , if it’s 32,it is the applicable frequency of 433MHz, if it’s
38, it is the applicable frequency of 470MHz, if it’s 45, it is the applicable frequency of
868MHz; If it’s 44, it is the applicable frequency of 915MHz; if it’s 46, it is the applicable
frequency of 170MHz; xx represents the version number, yy represents other features of
module.

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7.4 Reset instruction
Instruction format
Detailed description
C4+C4+C4
In sleep mode (M0=1, M1=1), a command (HEX format) is issued to the module serial port::
C4 C4 C4, the module will generate a reset; during the reset process, the module performs
self-test, AUX output low level, After the completion of reset, the AUX outputs high and the
module starts to work normally. At this time, Users can switch modes or initiate the next
instruction.
7.5 Parameter setting instruction
0
Name
Description
Note
0
HEAD
Fixed 0xC0 or 0xC2, which indicates that this frame data is a
control command
Must be 0xC0 or C2
C0 ：The set parameters will be saved
after power down.
C2：The set parameters will not be saved
after power down.。
1
ADDH
High byte of module address (default 00H)
00H-FFH
2
ADDL
Low byte of module address (default 00H)
00H-FFH
3
SPED
7
6
Serial parity bit
The serial port mode of the two
communication parties can be different
0
0
8N1（default）
0
1
8O1
1
0
8 E1
1
1
8N1（equals to 00）
5
4
3
TTL Serial port rate（bps）
The baud rate of both parties can be
different.
The serial port baud rate has nothing to
do with the wireless transmission
parameters, and does not affect the
wireless transmission and reception
characteristics.
0
0
0
Serial port baud rate 1200
0
0
1
Serial port baud rate 2400
0
1
0
Serial port baud rate 4800
0
1
1
Serial port baud rate 9600（default）
1
0
0
Serial port baud rate 19200
1
0
1
Serial port baud rate 38400
1
1
0
Serial port baud rate 57600
1
1
1
Serial port baud rate 115200
2
1
0
Wireless air data rate（bps）
The lower the air speed, the longer the
distance, the stronger the
anti-interference performance and the
longer the transmission time.
The wireless transmission rates of both
communicating parties must be the same.
0
0
0
Air data rate 1.2k（default）
0
0
1
Air data rate 2.4k
0
1
0
Air data rate 4.8k
0
1
1
Air data rate 9.6k
1
0
0
Air data rate 19.2k
1
0
1
Air data rate 38.4k
1
1
0
Air data rate 50k
1
1
1
Air data rate 70k
4
CHAN
7
6
5
Keep and unused
Write 0.
Communication channel
00H-FFH，correspond 425 ~ 450.5MHz

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4-0：（425M + CHAN * 0.1M), default 50H（433M）
5
OPTION
7
Fixed point send enable bit（similar to MODBUS）
When value is 1, the first 3 bytes of each
user data frame are used as the high and
low addresses and channels. When
transmitting, the module changes its own
address and channel, and when it is
finished, it restores the original settings.
0
Transparent transmission mode
1
Fixed point transmission mode
6
IO drive mode（default 1）
This bit is used to enable the internal
pull-up resistor of the module.
Open-drain mode is more adaptable, and
in some cases an external pull-up resistor
may be required.
1
TXD、AUX push-pull output，RXD pull up input
0
TXD、AUX open-drain outputs，RXD open-drain
inputs
5
4
3
Wireless wakeup time
Both transmitter and receiver module
work in mode 0. The delay time is invalid
and can be any value.
The transmitter works in mode 1, and
will continue to transmit the call code for
the corresponding time.
The receiver works in mode 2, which
refers to the receiver's listening interval
(wireless wake-up) and can only receive
data from the module working in mode 1.
0
0
0
250ms（default）
0
0
1
500ms
0
1
0
750ms
0
1
1
1000ms
1
0
0
1250ms
1
0
1
1500ms
1
1
0
1750ms
1
1
1
2000ms
2
FEC switch
After the FEC is turned off, the actual
data transmission rate is increased, but
the anti-interference ability is weakened
and the distance is slightly closer. Please
choose according to the actual
application. Both sides of
the communication must be turned on or
off.
0
Turn off FEC
1
Open FEC（default）
1
0
Transmitting power (Approximate value)
The external power supply must provide
more than 1A current output capability.
And ensure that the power supply ripple
is less than 100mV.
It is not recommended to use smaller
power transmission because of its low
power utilization efficiency.
0
0
27dBm（default）
0
1
24dBm
1
0
21dBm
1
1
18dBm
For example（The meaning of the No. 3 "SPED" byte）：
The binary digit of the byte
7
6
5
4
3
2
1
0
Specific value（Users configure）
0
0
0
1
1
0
1
0
Meaning
Serial parity bit
8N1
Serial port baud rate 9600
Air data rate 2.4k
Corresponding hexadecimal
1
A

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8. Hardware design
It is recommended to use a DC regulated power supply to supply power to the module. The power supply ripple
factor should be as small as possible, and the module needs to be reliably grounded.
Please pay attention to the correct connection of the positive and negative poles of the power supply. If the reverse
connection is made, the module may be permanently damaged.
Please check the power supply to ensure that it’s within the recommended power supply, or the module will be
permanently damaged if it exceeds the maximum value.
Please check the stability of the power supply, and the voltage cannot be fluctuated frequently;
When designing the power supply circuit for the module, it is often recommended to reserve more than 30% of the
margin, which is beneficial for long-term stable operation of the whole machine
The module should be as far away as possible from the power supply, transformers, high-frequency wiring and other
parts with large electromagnetic interference;
High-frequency digital routing, high-frequency analog routing, and power routing must be avoided under the
module. If it is necessary to pass the module, it is assumed that the module is soldered to the Top Layer, and the
copper is applied to the Top Layer of the module contact part(Copper is well grounded), and must be close to the
digital part of the module and routed in the Bottom Layer;
Assuming that the module is soldered or placed in the Top Layer, it is also wrong to randomly route the Bottom
Layer or other layers, which will affect the spurs and receiving sensitivity of the module in varying degrees;
Assume that there are devices with large electromagnetic interference around the module that will greatly affect the
performance of the module. It is recommended to keep away from the module according to the strength of the
interference. If necessary, appropriate isolation and shielding can be done.
Assume that there are traces with large electromagnetic interference around the module (high-frequency digital,
high-frequency analog, power trace), which will greatly affect the performance of the module. It is recommended to
stay away from the module according to the strength of the interference. If possible, users can do some proper
isolation and shielding;
If the communication line uses 5V level, it must be connected in series with 1k-5.1k resistor (not recommended,
there is still risk of damage);
Try to stay away from some physical layers which is 2.4GHz TTL protocol, for example: USB3.0;
The antenna installation structure has a great influence on the performance of the module. Make sure that the
antenna is exposed, preferably vertically. When the module is installed inside the casing, a good antenna extension
cable can be used to extend the antenna to the outside of the casing;
The antenna can not be installed inside the metal case, which will greatly reduce the transmission distance.

Chengdu Ebyte Electronic Technology Co.,Ltd. E31-433T27D User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
18
9. FAQ
9.1 Transmission distance is not ideal
When there is a linear communication obstacle, the communication distance will be correspondingly reduced;
Temperature, humidity, and co-channel interference will lead to an increase in communication packet loss rate;
The ground absorbs and reflects radio waves, so the test results close to the ground are poor.
Seawater has a strong ability to absorb radio waves, so the seaside test results are poor.
There are metal objects near the antenna, or placed in the metal shell, the signal attenuation will be very serious;
Power register setting error, air data rate setting is too high (the higher the air data rate, the closer the distance);
The low voltage of the power supply is lower than the recommended value at room temperature, and the lower the
voltage, the smaller the power;
The matching degree of antenna and module is poor, or the quality of the antenna itself.
9.2 Module is easy to damage
Please check the power supply to ensure that it’s within the recommended power supply, or the module will be
permanently damaged if it exceeds the maximum value.
Check the stability of the power supply and the voltage cannot be fluctuated frequently.
Please ensure that the installation process is anti-static, and the high-frequency components are electrostatically
sensitive.
Please ensure that the humidity during installation and use is not too high because some components are humidity
sensitive devices.
If there is no special demand, it is not recommended to use it at too high or too low temperature.
9.3 Bit error rate is too high
There are co-channel signal interference nearby, away from interference sources or modify frequency and channel
to avoid interference;
The undesirable power supply may also cause messy code, and ensure the reliability of the power supply.
The quality of extension line and feeder are poor or too long, which also cause high bit error rate;

Chengdu Ebyte Electronic Technology Co.,Ltd. E31-433T27D User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
19
10. Welding operation guidance
This type is full-sized module, when the welder welds the module, he must be welding according to the anti-static
regulation. This product is allergic to static, randomly welding the module will have the chance of damaging it
permanently.