Ebyte E840-TTL-NB03 User manual

E840-TTL-NB03 User Manual
NB Wireless Module

Chengdu Ebyte Electronic Technology Co., Ltd. E840-TTL-NB03 User Manual
Copyright ©2012–2019, Chengdu Ebyte Electronic Technology Co.,Ltd.
1
Contents
FEATURE............................................................................................................................................................................. 2
1. PRODUCT OVERVIEW................................................................................................................................................. 2
1.1 INTRODUCTION.............................................................................................................................................................. 2
1.2 PARAMETER................................................................................................................................................................... 2
1.3 INTERFACE DESCRIPTION............................................................................................................................................... 4
1.4 PIN DEFINITION.............................................................................................................................................................. 4
2．QUICK START...............................................................................................................................................................6
2.1 HARDWARE PREPARATION............................................................................................................................................. 6
2.2 DATA TRANSMITTING TEST............................................................................................................................................7
2.2.1 WORKING MODE：..................................................................................................................................................... 8
3. AT COMMAND..............................................................................................................................................................10
4. NOTES.............................................................................................................................................................................18
5．IMPORTANT STATEMENT...................................................................................................................................... 18
6．REVISION HISTORY................................................................................................................................................. 18
7. ABOUT US......................................................................................................................................................................19

Chengdu Ebyte Electronic Technology Co., Ltd. E840-TTL-NB03 User Manual
Copyright ©2012–2019, Chengdu Ebyte Electronic Technology Co.,Ltd.
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E840-TTL-NB03 is developed for serial port devices and network servers to transmit data
through the network. It supports B8 frequency band. It can be easily set up with simple AT
commands. It can be used to realize serial-to-network two-way data transparency transmission. This
chapter is a quick introduction to the E840-TTL-NB03 product. It is the easiest hardware
environment to test the E840-TTL-NB03 network transmission function, that is, realize the two-way
transparent transmission of data from the serial device (the computer) to the network server.
Feature
It meets almost all M2M application needs；
Support data transparent transmission, support TCP/UDP network protocol, and heartbeat packet and
registration package function can be customized；
Serial port caching is supported. The serial port data can be cached locally before the server is connected；
The maximum downlink rate of NB data is 85.6 kbps, and the maximum uplink rate is 85.6 kbps；
Supports protocols such as TCP/UDP, encoding formats CS-1, CS-2, CS-3, and CS-4
1. Product overview
1.1 Introduction
E840-TTL-NB03 is a NB data transmission module developed by Ebyte. The software is fully functional and covers
most common application scenarios. Users can realize two-way data transparency from serial port to network server
through simple setup transmission.
The module uses 2.0mm pin headers to facilitate customer device integration, using 5V ~ 20V voltage supply.
Support mobile NB card, communication and LED indication with compatible level, default 3.3V can be applied to 5V
level, with anti-interference ability, can be used in some environments with strong electromagnetic interference, such as
some power industry.
1.2 Parameter
Name
Value
Description
Hardware
features
Frequency
B8
Module will search frequency automatically
NB data feature
NB data downlink transmission：max 85.6kbps
NB data uplink transmission：max 85.6kbps
Coding format：CS-1、CS-2、CS-3 and CS-4
Support for PAP (Password Authentication Protocol) protocols
commonly used for PPP connections
Support usually used for CHAP (Interrogation Handshake
Authentication Protocol) protocol
Embedded protocol: TCP/UDP etc
Support for unstructured supplementary data services (USSD)

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Software features
Antenna
IPEX
IoT cloud
Ebyte-IOT
Data interface
[email protected]，compatible with 5V
Baud rate
Max 230400bps，default 115200bps
Tx power
23dBm±2dB
Power saving（typical value）
In power saving mode, max current consumption：5μA
In power saving mode, typical current consumption：3.5μA
Working Temperature
-30℃- +70℃；working at -40℃~+85℃
Working Voltage
DC：5V~20V；Battery：2.5V~3.6V
Size
42×40×9.7 mm
SIM
MICRO SIM card
3GPP Frequency
1 Timeslot
2 Timeslot
4 Timeslot
CS-1
9.05kbps
18.1kbps
36.2kbps
CS-2
13.4kbps
26.8kbps
53.6kbps
CS-3
15.6kbps
31.2kbps
62.4kbps
CS-4
21.4kbps
42.8kbps
85.6kbps

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1.3 Interface description
1.4 Pin definition
Pin no.
Name
Function
1
RST
Module reset
2
IORT
The low level lasts for 3~10S, the module parameters will be restored to the factory settings, and
will be restarted immediately.
3
LINK
The link connection status indication pin corresponds to the onboard left 1 LED.
High: Successful connection to the web server;
Low: failed to connect to the web server;
4、24、25
NC
Not used
5
DATA
Data transmission and reception indication pin, when the network receives data or the serial port
receives data (50ms high/10ms low), corresponding to the onboard third LED light from the left.
6
STAT
The device status indication pin corresponds to the onboard second LED from the left.
Low: The device is powered on to search for SIM card1800ms low, 200ms high: the device
checks the correct SIM card and is attaching to the network;
High: The device is attached to the network successfully.
7
RXD
Data receiving pin，default 3.3V，compatible with 5V
8
TXD
Data transmitting pin，default 3.3V，compatible with 5V

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9
VEF
Drive level power supply pin, if you need to achieve 5V serial communication and LED
indication is 5V drive level, you need to input 5V level on this pin.
10、11、14、
15、23
MOD、SLE、
PA6、PA7、EN
Unavailable
12
4V2
Lithium battery power supply pin, power supply range: 2.5V~3.6V. This pin is prohibited from
being reversed and is not allowed to be supplied with VCC.
16
VCC
DC power supply pin, power supply range: 5V~20V. This pin is prohibited from being reversed
and is not allowed to be supplied with 4V2.
19
VD
Connect to external SIM card power supply pin, if the onboard SIM card holder is used, the pin
NC can be used.
20
RS
Connect to external SIM reset pin, if the onboard SIM card holder is used, the pin NC can be
used.
21
DA
Connect to external SIM data pin, if the onboard SIM card holder is used, the pin NC can be
used.
22
CL
Connect to external SIM clock pin, if the onboard SIM card holder is used, the pin NC can be
used.
13、17、18
GND
Ground

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2．Quick start
2.1 Hardware preparation
Before testing, please connect serial port line as per recommended circuit, there are SIM card and antenna.
1. Enter the AT command mode and send +++ in the serial port assistant (except that +++ does not need to
check to send a new line, other AT commands need to tick to send a new line to be valid), you must send +++
command 3s Sending any other AT command (except for restarting the AT command) can completely enter the
AT command mode.
2. After entering the AT command mode, use AT+CPIN to check the SIM card access:
For example: AT+CPIN
+OK=1
Indicates that the SIM card is connected and uses AT+CSQ to view the current signal strength:
For example: AT+CSQ+OK=26Indicates that the current signal strength is normal.
If the response is 99, the current signal strength is abnormal. Check whether the current antenna is connected
or the surrounding base station is abnormal.
3. Access server, AT+SOCK=TCPC, 116.62.42.192, 31687 (parameters are separated by commas in English
characters, and IP commands are separated by English characters).SOCK settings
For example: AT+SOCK=TCPC, 116.62.42.192, 31687
+OK
Indicates that the setting was successful.
4. Restart (all AT commands modify parameters, the device will take effect after restart) After the execution
command AT+REBT returns OK, the device restarts immediately. Here, the IP only performs the demonstration.
The actual connection is based on the IP of the server to be connected.

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5. After the base station is connected, the NET light is always on to indicate that the server is connected,
and transparent transmission can be performed at this time.
2.2 Data Transmitting Test
Software is needed for data transmitting test:
Xcom is applied here for the test and you can download it at our website. Users can also apply other test tools that
are available.

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2.2.1 Working mode：
1. Working mode：Transparent transmission mode, AT configuration mode, cloud platform mode
a) Transparent transmission mode: After power-on, the module works in the transparent transmission mode by default,
and automatically starts the network connection. When the connection is established with the server, any data received by
the serial port will be transparently transmitted to the server. At the same time, it can also receive the number from the
server. After receiving the server data, the module will output directly through the serial port. The maximum length of
data supported by this module is 486 bytes.
This module supports one-way Socket connection. The user can be configured as TCP Client or UDP Client. In
transparent transmission mode, the received serial port data will be directly transmitted to the network server, and the
received network server data will be directly output through the serial port.
b) AT mode: In this mode, the serial port data is regarded as an AT command.
c) Cloud platform mode: The E840-DTU (NB-03) configuration tool can be used to switch to the cloud platform mode.
After the configuration is completed, the data can be tested. It should be noted that the maximum data of the single
package in the cloud platform working mode is 100. , the time interval for sending data packets is not less than 5s.
d) Mode switching. After the serial port receives the “+++” frame data in the transparent transmission mode, the RX pin
receives any AT command within 3 seconds, and the mode switches to the AT mode. In AT mode, send
AT+EXAT<CR><LF> to switch to transparent transmission mode.
2. Network function
a) Short connection: In TCP Client mode, the short connection function is enabled. If there is no data reception in the
serial port or network port within the set time, the network connection will be automatically disconnected. The short
connection function is turned off by default. The connection time can be set from 2 to 65535 seconds. When set to 0, the
short connection function is disabled.
b) Registration packet: The registration packet is closed by default. The total of 4 options are: send physical address
when connecting, send custom data when connecting, add physical address before each packet of data, add custom data
before each packet of data, customize The maximum length of the registration packet is 40 bytes (when set to HEX
format, the maximum length is 20 bytes).
c) Heartbeat packet: In the idle state of network communication, the heartbeat packet is used for network state

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maintenance. The heartbeat period can be set from 0 to 65535 seconds, and the maximum length of the heartbeat packet
is 40 bytes (when set to HEX format, the maximum length is 20 bytes). Supports two heartbeat types, network heartbeat,
serial heartbeat, selects network heartbeat, starts timing with communication idle, and sends heartbeat packets to the
server according to the configured heartbeat period. Select the serial port heartbeat, start timing with communication idle,
and send heartbeat packets to the serial port according to the configured heartbeat period.
d) Clear the cache: Before the connection to the server is established, the data received by the serial port will be cached.
When the connection with the server is established, you can choose whether to clear the cached data. By default, the
cache is cleared.
The maximum packet length of the local cache is 512 bytes.
3. Ebyte Internet of Things platform function
After the AT+EBTIOT command is used to set whether the module will enable the transparent transmission function of
the Ebyte cloud platform, after the device is turned on, the information such as the heartbeat and registration packet
configured by the user will be invalid. The user only needs to set the forwarding relationship of the corresponding device
to the platform to implement the device. Data is transparent. For specific operations, please refer to the "Ebyte Special
Cloud Platform Transparent Transmission Guide".

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3. AT Command
a) Command format: AT+<CMD>[op][ para1, para2, para3,…]<CR><LF>
AT+: Command prefix
CMD: Control command
[op]: “=” Parameter configuration
“NULL” Parameter query
[para-n]: List of parameters, can be omitted
<CR><LF>: Line Feed，ASCII 0x0D 0x0A
b) Command error code:
Error code
Description
-1
Invalid command format
-2
Invalid command
-3
Invalid operator
-4
Invalid parameter
-5
Operation not allowed
c) Command set:
Command
Description
REBT
Restart
VER
Query version number
INFO
Query device information
EXAT
Exit AT command mode
RESTORE
Restore factory settings
UART
Set/query serial port parameters
UARTCLR
Set/Query whether to clear the serial port cache before connecting
MAC
Query MAC address
IMEI
Query IMEI
SN
Set/query SN code
LINKSTA
Query the SOCK connection status
SOCK
Set/query SOCK parameters
REGMOD
Set/Query Registration Packet Mode
REGINFO
Set/Query User Registration Packet information (ASCII)
REGINFONEW
Set/Query User Registration Packet information (HEX)
HEARTMOD
Set/query heartbeat packet mode
HEARTINFO
Set/Query User Heartbeat Packet information (ASCII)
HEARTINFOEW
Set/Query User Heartbeat Packet information (HEX), Supporting index
HEARTM
Set/query heartbeat time
SHORTM
Set/query short connection time
CDEBYTEIOT
Set/query the IP and port address of the Ebyte IoT cloud platform

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EBTIOT
Set/query the Ebyte IoT cloud platform enable
CREG
Query whether to register to the network
CSQ
Query signal strength
CPIN
Query SIM card status
LBS
Query LAC & CID code
RSTIME
Set/query reset time
d) Command details:
AT+REBT
Function: Restart the device.
Format: Set
Send: AT+REBT<CR>
Return: <CR><LF>+OK<CR><LF>
Para: None
Note: After the command is executed correctly, the device restarts immediately and enters the transparent
transmission mode after restarting.
AT+VER
Function: Query firmware version.
Format: Set
Send: AT+VER<CR><LF>
Return: <CR><LF>+OK=<ver><CR><LF>
Para: ver firmware versin
Note: None
AT+INFO
Function: Query device type and version information
Format: Set
Send: AT+INFO<CR><LF>
Return: <CR><LF>+OK=<mod_name>,<hw_ver>,<sw_ver><CR><LF>
Para: mod_name Device name
hw_ver Hardware version
sw_ver Software version
Note: None
AT+EXAT
Function: Exit command mode and enter transparent transmission mode.
Format: Set
Send: AT+EXAT<CR><LF>
Return: <CR><LF>+OK<CR><LF>
Para: None
Note: After the command is executed correctly, the device switches from command mode to transparent
transmission mode.

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AT+RESTORE
Function: Restore factory settings.
Format: Set
Send: AT+RESTORE<CR><LF>
Return: <CR><LF>+OK<CR><LF>
Para: None
Note: None
AT+UART
Function: Set/Query UART parameters.
Format: Query
Send: AT+UART<CR>
Return: <CR><LF>+OK=<baudrate>,< parity ><CR><LF>
Set
Send: AT+UART=<baudrate>,< parity ><CR><LF>
Return: <CR><LF>+OK<CR><LF>
Para: baudrate, can be configured to: 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600.
Parity Parity bit NON
E No Check EVEN Even check ODD Odd check
Note: None
AT+UARTCLR
Function: Set/Query whether to clear the serial port cache before connecting.
Format: Query
Send: AT+ UARTCLR <CR>
Return: <CR><LF>+OK=< sta ><CR><LF>
Set
Send: AT+ UARTCLR =< sta ><CR>
Return: <CR><LF>+OK<CR><LF>
Para: sta status
ON Clear the serial port cache before connecting
OFF Don’t clear the serial port cache before connecting
AT+MAC
Function: Query device MAC.
Format: Query
Send: AT+MAC<CR>
Return: <CR><LF>+OK=<mac><CR><LF>
Para: mac Device MAC address
AT+IMEI
Function: Query device IMEI.
Format: Query
Send: AT+IMEI<CR>

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Return: <CR><LF>+OK=<imei><CR><LF>
Para: imei Device IMEI code
AT+SN
Function: Set/Query SN.
Format: Query
Send: AT+SN<CR>
Return: <CR><LF>+OK=<sn><CR><LF>
Set
Send: AT+SN=<sn><CR>
Return: <CR><LF>+OK<CR><LF>
AT+LINKSTA
Function: Query whether the TCP link has been established.
Format: Query
Send: AT+LINKSTA<CR>
Return: <CR><LF>+OK=<sta><CR><LF>
Para: Sta Connect(TCP Connected) / Disconnect(TCP Disconnected)
AT+SOCK
Function: Set/Query network protocol parameter format.
Format: Query
Send: AT+SOCK<CR>
Return: <CR><LF>+OK=<protocol>,<ip>,< port ><CR><LF>
Set
Send: AT+SOCK=<protocol>,<ip>,< port ><CR>
Return: <CR><LF>+OK<CR><LF>
Para: protocol TCPC / UDPC
TCPC: TCP client
UDPC: UDP client
ip The IP address or domain name of the target server
port Server port number, in decimal, less than 65535.
AT+REGMOD
Function: Set/Query registration packet mechanism.
Format: Query
Send: AT+REGMOD<CR>
Return: <CR><LF>+OK=<status><CR><LF>
Set
Send: AT+REGMOD =<status><CR>
Return: <CR><LF>+OK<CR><LF>
Para: status Registration packet mechanism
EMBMAC Add MAC/IMEI as registration packet data before each packet sent to the server
EMBCSTM Add user registration packet data before each packet sent to the server

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OLMAC Send a MAC/IMEI registration packet only when connecting to the server at the first
time
OLCSTM Send a user registration packet only when connecting to the server at the first time
OFF Registration packet mechanism off
AT+REGINFO
Function: Set/Query the contents of the user registration packet.
Format: Query
Send: AT+ REGINFO <CR>
Return: <CR><LF>+OK=<data><CR><LF>
Set
Send: AT+ REGINFO =<data><CR>
Return: <CR><LF>+OK<CR><LF>
Para: data Less than 40 bytes ASCII code
AT+REGINFONEW
Function: Set/Query the contents of the user registration packet.
Format: Query
Send: AT+ REGINFONEW<CR>
Return: <CR><LF>+OK=<type>,<data><CR><LF>
Set
Send: AT+ REGINFONEW =<type>,<data><CR>
Return: <CR><LF>+OK<CR><LF>
Para: type
0 registration packet is HEX
1 registration packet is ASCII code
data
Less than 40 bytes ASCII code, when the registration packet type is HEX, the content must be in the
legal HEX format and the length must be an even number
AT+HEARTMOD
Function: Set/Query heartbeat packet mode.
Format: Query
Send: AT+ HEARTMOD<CR>
Return: <CR><LF>+OK=<mode><CR><LF>
Set
Send: AT+ HEARTMOD=<mode><CR>
Return: <CR><LF>+OK<CR><LF>
Para: mode
NET Network heartbeat packet
UART UART heartbeat packet
AT+HEARTINFO
Function: Set/Query heartbeat packet data.

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Format: Query
Send: AT+ HEARTINFO<CR>
Return: <CR><LF>+OK=<data><CR><LF>
Set
Send:AT+ HEARTINFO=<data><CR>
Return: <CR><LF>+OK<CR><LF>
Para: data Less than 40 bytes ASCII code
AT+HEARTINFONEW
Function: Set/Query heartbeat packet data.
Format: Query
Send: AT+ HEARTINFONEW<CR>
Return: <CR><LF>+OK=<type>,<data><CR><LF>
Set
Send: AT+ HEARTINFO=<type>,<data><CR>
Return: <CR><LF>+OK<CR><LF>
Para: type
0 Heartbeat packet data is HEX
1 Heartbeat packet data is ASCII code
data
Less than 40 bytes ASCII code, when the registration packet type is HEX, the content must be in the
legal HEX format and the length must be an even number
AT+HEARTM
Function: Set/Query heartbeat packet time.
Format: Query
Send: AT+ HEARTM <CR>
Return: <CR><LF>+OK=<time><CR><LF>
Set
Send: AT+ HEARTM =<time><CR>
Return: <CR><LF>+OK<CR><LF>
Para: time
Heartbeat time 0 OFF, range 1～65535 seconds
AT+SHORTM
Function: Set/Query short connection time.
Format: Query
Send: AT+ SHORTM<CR>
Return: <CR><LF>+OK=<time><CR><LF>
Set
Send: AT+ SHORTM=<time><CR>
Return: <CR><LF>+OK<CR><LF>
Para: time
Short connection time 0 OFF, range 2～65535 seconds

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AT+ CDEBYTEIOT
Function: Set/Query the IP and port address of the Ebyte IoT cloud platform.
Format: Query
Send: AT+ CDEBYTEIOT<CR>
Return: <CR><LF>+OK=<ip>,<port><CR><LF>
Set
Send: AT+ CDEBYTEIOT=<ip>,<port><CR>
Return: <CR><LF>+OK<CR><LF>
AT+EBTIOT
Function: Set/Query Ebyte IoT platform.
Format: Query
Send: AT+EBTIOT <CR>
Return: <CR><LF>+OK=<ctrl><CR><LF>
Set
Send: AT+EBTIOT =<ctrl><CR>
Return: <CR><LF>+OK<CR><LF>
Para: ctrl Ebyte IoT platform switch ON Turn on / OFF Turn off
Note: After the IoT cloud function is enabled, the device is automatically connected to the Ebyte IoT platform,
ignoring the sock configuration and registration packet, heartbeat packet function.
AT+CSQ
Function: Query signal strength.
Format: Query
Send: AT+CSQ<CR><LF>
Return: <CR><LF>+OK=<csq><CR><LF>
Para: csq signal strength
Note: None
AT+CREG
Function: Query whether to register to the operator network.
Format: Query
Send: AT+CREG<CR><LF>
Return: <CR><LF>+OK=<creg><CR><LF>
Para: creg
1 Registered to the network
0 Not registered to the network
Note: None
AT+CPIN
Function: Query SIM card status.
Format: Query
Send: AT+CPIN<CR><LF>

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Return: <CR><LF>+OK=<cpin><CR><LF>
Para: cpin
1 SIM card detected
0 No SIM card detected
Note: None
AT+LBS
Function: Query LAC & CID code.
Format: Query
Send: AT+LBS<CR><LF>
Return: <CR><LF>+OK=<lac><cid><CR><LF>
AT+RSTIME
Function: Set/Query reset time.
Format: Query
Send: AT+RSTIME<CR><LF>
Return: <CR><LF>+OK=<rstime><CR><LF>
Set
Send: AT+RSTIME=<rstime><CR><LF>
Return: <CR><LF>+OK<CR><LF>

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4. Notes
1. The Socket link of this device will always be opened. After the initialization is successful, it will automatically
establish a connection with the configured network server.
2. After the device is powered on, it cannot be initialized successfully. That is, the "state" indicator has no indication for
more than 30 seconds. In this case, check whether the module is installed properly, whether the SIM card is properly
inserted, and whether the SIM has been invalid.
3. The short connection feature can be used to reduce the connection pressure of multiple devices to the server. After the
short connection function is enabled (AT+SHORTM>2), when the network or serial port has no data for more than the
short connection setting cycle, the device will actively disconnect the connection. After disconnection, the network
cannot send data. When the serial port sends valid data, the device will immediately establish a connection with the
server. If the local clear cache function is turned off, the current packet will be cached (up to 10K bytes). After the
connection is successful, the data will be sent to the server. If the clear local cache function is enabled, the packet will be
discarded.
4. The heartbeat function is used to maintain the state after the device and the server are successfully connected. Because
if the client and the network server successfully establish a connection and there is no data transmission for a long time,
the Socket link may be “dead”, that is, the link exists, but cannot send or receive data. Therefore, in actual use, it is
recommended to enable the heartbeat packet function to ensure the reliability of the network link.
5. In actual use, it is normal that there is different data delay of two communications.
6. When the device serial port outputs the words "pdp error, device will be reset!", it indicates that the PDP context is
disabled by the network. Maybe the SIM card is loose or the current network channel is occupied abnormally.
5．Important Statement
1. Ebyte reserves the right of final interpretation and modification of all the contents of this manual.
2. As the hardware and software products continuously improving, this manual may subject to change without notice,
please refer to the latest version.
3. Everyone is responsible for protecting the environment: to reduce the use of paper, we only provide electronic
documents of the English manual, if necessary, please go to our official website to download.
6．Revision history
Version
Date
Specification
Issued by
1.1
2019-05-30
Initial version
Blue
1.2
2019-07-05
Revised version
Lyl

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7. About Us
Ebyte after-sales technical support：[email protected]om
For file download and more product information, please visit：www.ebyte.com
Any questions or suggestions, please contact：supp[email protected]
Tel：[phone]
Fax：[phone]
Website：www.cdebyte.com/en/
Address：Innovation Center B333-D347, 4# XI-XIN Road, Chengdu, Sichuan, China