Ebyte E104-BT51 User manual

E104-BT51 User Manual
CC2640R2F BLE5.0 Low power consumption
Bluetooth to serial port module

Chengdu Ebyte Electronic Technology Co.,Ltd. E104-BT51 User Manual
Copyright ©2012–2019，Chengdu Ebyte Electronic Technology Co.,Ltd.
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CONTENT
1. OVERVIEW.............................................................................................................................................................. 4
1.1 BRIEF INTRODUCTION............................................................................................................................................ 4
1.2 FEATURES.............................................................................................................................................................. 4
1.3 APPLICATION..........................................................................................................................................................5
2. SPECIFICATION AND PARAMETER................................................................................................................ 5
2.1 LIMIT PARAMETER................................................................................................................................................. 5
2.2 OPERATING PARAMETER........................................................................................................................................ 5
3. SIZE AND PIN DEFINITION.................................................................................................................................7
4. RECOMMENDED CONNECTION DIAGRAM................................................................................................. 9
5. FUNCTION DESCRIPTION.................................................................................................................................. 9
5.1 POWER MODE......................................................................................................................................................... 9
5.1.1 Low power consumption mode.......................................................................................................................9
5.1.2 Wake-up mode.............................................................................................................................................. 10
5.2 DATA VALID INDICATION..................................................................................................................................... 10
5.3 GPIO LEVEL READING......................................................................................................................................... 11
5.4 GPIO LEVEL OUTPUT...........................................................................................................................................11
5.5 PWM OUTPUT..................................................................................................................................................... 11
5.6 ADC ACQUISITION...............................................................................................................................................12
5.7 BATTERY VOLTAGE SERVICE................................................................................................................................ 12
5.8 MAC ADDRESS BINDING..................................................................................................................................... 13
5.9 BLUETOOTH MAXIMUM PACKET LENGTH MTU CONFIGURATION.......................................................................14
5.10 UUID CONFIGURATION.....................................................................................................................................14
5.11 BROADCAST DATA CAN BE SWITCHED............................................................................................................... 14
5.12 CONFIGURATION OVER AIR................................................................................................................................ 15
5.13 STATUS OR EVENT PRINTING.............................................................................................................................. 16
6. OPERATION COMMAND................................................................................................................................... 16
6.1 AT COMMAND TEST............................................................................................................................................. 18
6.2 READ AND CONFIGURE BAUD RATE.....................................................................................................................18
6.3 READ AND CONFIGURE STOP BIT......................................................................................................................... 18
6.4 READ AND SET SERIAL PARITY............................................................................................................................ 19
6.5 SET AND READ SERIAL DATA LENGTH................................................................................................................. 19
6.6 CHECK THE CURRENT BROADCAST STATUS,TURN ON GENERAL BROADCAST, IBEACON BROADCAST,TURN
BROADCAST............................................................................................................................................................... 19
6.7 QUERY AND SET GENERAL BROADCAST DATA (SAVE WHEN POWER OFF)............................................................19
6.8 QUERY AND SET GENERAL BROADCAST DATA (DO NOT SAVE WHEN POWER OFF)...............................................20
6.9 QUERY AND SET IBEACON MAJOR BROADCAST DATA........................................................................................20
6.10 QUERY AND SET IBEACON MINOR BROADCAST DATA...................................................................................... 20
6.11 QUERY AND SET IBEACON UUID...................................................................................................................... 20
6.12 QUERY AND SET IBCTXPWR........................................................................................................................... 21
6.13 READ AND SET THE DEVICE NAME (SAVE WHEN POWER DOWN)....................................................................... 21
6.14 READ AND SET THE DEVICE NAME (DO NOT SAVE WHEN POWER OFF).............................................................. 21
6.15 READ SOFTWARE VERSION NUMBER.................................................................................................................. 22
6.16 READ AND SET BROADCAST INTERVAL.............................................................................................................. 22

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6.17 READ AND SET THE MINIMUM CONNECTION INTERVAL.....................................................................................22
6.18 READ AND SET THE MAXIMUM CONNECTION INTERVAL....................................................................................22
6.19 READ AND SET TIMEOUT....................................................................................................................................23
6.20 SET AND QUERY DELAY TIMES........................................................................................................................... 23
6.21 DISCONNECT THE CURRENT CONNECTION.........................................................................................................23
6.22 QUERY THE CURRENT CONNECTION STATUS......................................................................................................23
6.23 QUERYING THE LOCAL MAC ADDRESS............................................................................................................ 23
6.24 QUERY THE MAC ADDRESS OF THE CONNECTED DEVICE................................................................................. 24
6.25 READ MAC BINDING STATUS,ENABLE OR DISABLE MAC BINDING................................................................ 24
6.26 READ AND SET BINDING MAC.......................................................................................................................... 24
6.27 QUERY AND SET THE MTU LENGTH..................................................................................................................24
6.28 QUERY AND SET THE UUID LENGTH OF THE TRANSPARENT TRANSMISSION SERVICE..................................... 25
6.29 QUERY AND SET THE BLUETOOTH SERVICE UUID............................................................................................25
6.30 QUERY AND SET THE BLUETOOTH READ SERVICE UUID..................................................................................25
6.31 QUERY AND SET THE BLUETOOTH WRITE SERVICE UUID.................................................................................25
6.32 QUERY,ENABLE,DISABLE SERIAL PORT DELAY.................................................................................................26
6.33 RESTART COMMAND.......................................................................................................................................... 26
6.34 RESTORE FACTORY............................................................................................................................................ 26
6.35 AUTHENTICATE CONFIGURATION OVER AIR PASSWORD.....................................................................................26
6.36 UPDATE AND QUERY CONFIGURATION OVER AIR PASSWORD............................................................................ 27
6.37 QUERY AND SET TRANSMIT POWER....................................................................................................................27
6.38 ENTER SLEEP IMMEDIATELY...............................................................................................................................27
6.39 QUERY AND SET PRINTING STATUS.................................................................................................................... 27
6.40 READ IO INPUT..................................................................................................................................................28
6.41 SET AND READ IO OUTPUT................................................................................................................................ 28
6.42 SET AND READ PWM ENABLE...........................................................................................................................28
6.43 SET AND QUERY PWM OUTPUT PERIOD............................................................................................................ 28
6.44 SET AND QUERY PWM DUTY CYCLE................................................................................................................. 29
6.45 QUERY ADC SAMPLING VALUE......................................................................................................................... 29
6.46 SET AND READ THE MAXIMUM BATTERY VOLTAGE........................................................................................... 29
6.47 SET AND QUERY THE MINIMUM BATTERY VOLTAGE...........................................................................................29
6.48 QUERY RSSI...................................................................................................................................................... 30
7. UUID DESCRIPTION............................................................................................................................................30
7.1 EBYTE DATA TRANSMISSION UUID..................................................................................................................... 30
7.2 STANDARD BATTERY VOLTAGE SERVICE UUID................................................................................................... 30
8. QUICK START....................................................................................................................................................... 31
8.1 QUICK GUIDE TO CONFIGURATION MODE.......................................................................................................... 31
8.2 QUICK GUIDE TO TRANSPARENT TRANSMISSION AND CONFIGURATION OVER AIR MODE.................................32
8.3 GUIDE TO BLUETOOTH BATTERY SERVICE........................................................................................................... 40
9. HARDWARE DESIGN.......................................................................................................................................... 41
10. FAQ.........................................................................................................................................................................42
10.1 COMMUNICATION RANGE IS TOO SHORT......................................................................................................... 42
10.2 MODULE IS EASY TO DAMAGE.........................................................................................................................43
10.3 BIT ERROR RATE IS TOO HIGH..........................................................................................................................43

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11. WELDING OPERATION GUIDANCE............................................................................................................. 43
11.1 REFLOW SOLDERING TEMPERATURE................................................................................................................. 43
11.2 REFLOW SOLDERING CURVE..............................................................................................................................44
12. RELATED MODELS................................................................................................................................................44
13. BATCH PACKAGING.........................................................................................................................................46
14. REVISION HISTORY..........................................................................................................................................46
15. ABOUT US.............................................................................................................................................................47

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1. Overview
1.1 Brief introduction
E104-BT51 is a serial to BLE Bluetooth slave module based on
Bluetooth protocol version 5.0, which is small-sized, low power
consumption, and works in the 2.4GHz frequency band.
E104-BT51 module is a serial to BLE Bluetooth module developed
by Chengdu Ebyte Electronic Technology Co., Ltd. based on TI
CC2640R2F chip. This module uses AT commands to set parameters,
and is easy to operate and configure. The module only supports the
Bluetooth slave mode. The module functionally supports low-power
broadcasting with changeable content, transparent transmission of data and continuous transmission of files with variable
baud rate. It supports air command configuration and IO port level reading , IO port switch level setting, PWM output
with variable frequency and period, AD analog acquisition, Bluetooth battery voltage service. The module can be widely
used in smart wear, home automation, home security, personal health care, smart appliances, accessories and remote
control, automotive electronics, lighting industry, industrial internet, smart data collection, smart control, etc. The
module supports a maximum baud rate of 921600bps and a 2M PHY air rate of Bluetooth 5.0.
1.2 Features
Support Bluetooth BLE 5.0 protocol;
Support adjustable Bluetooth packet length;
Support two operating modes of configuration and transparent transmission;
Support auto-broadcast and auto-connection upon power on;
Support IBeacon and general broadcast switching;
Support broadcast data can be set;
Support MAC address binding;
Support multiple serial port modes and baud rates;
Support customized 16-bit UUID and 128-bit UUID;
Support Bluetooth parameter configuration over air;
Maximum communication distance up to 75m (0dBm);
Support ultra-low power consumption sleep mode, and broadcasts data synchronously and connection is maintained
Support IO port level reading;
Support IO port level output;
Support PWM output with variable frequency period;
Support ADC analog acquisition;
Support battery voltage detection service;
Support 2M, 1M airspeed;
MTU data transmission unit maximum 230 bytes;
Built-in PCB antenna, no external antenna required;

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1.3 Application
Wireless meter reading and sensing
Smart home
Industrial remote control and telemetry
Smart buildings, smart construction
Automatic data collection
Health sensor
Smart wearable device
Smart robot
Wireless sensing
Electronic label
Intelligent control
2. Specification and parameter
2.1 Limit parameter
Main Parameter
Performance
Note
Min
Max
Voltage supply [V]
0
3.6
Voltage over 3.8V will cause permanent damage
to module
Blocking power [dBm]
-
10
Chances of burn is slim when modules are used
in short distance
Operating temperature [℃]
-40
+85
Industrial grade
2.2 Operating parameter
Main parameter
Performance
Note
Min
Typ
Max
Operating voltage[V]
1.8
3.3
3.6
≥3.3 V ensures output power
Communication level [V]
3.0
For 5V TTL, it may be at risk of burning down
Operating temperature [℃]
-40
-
+85
Industrial design
Frequency [MHz]
2402
-
2480
Support ISM band
Power
consumption
Transmitting current
（mA）
-
9.1
Receiving current
（mA）
-
6.1
Sleep current（μA）
-
1.2
Software shutdown
Maximum Transmitting power [dBm]
4.6
5
5.5
Receiving sensitivity [dBm]
-98.5
-99
-100.5
Air rate is 250k bps

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Sleep broadcast current(Default)
-
29.93
-
Unit：uA. Broadcast interval is 1s
Wake up broadcast current (Default)
-
1581
-
Unit：uA. Broadcast interval is 1s
Wake up no broadcast
current(Default)
-
1570
-
Unit：uA。
Wake up connection current(Default)
-
2301
-
Unit：uA. Connection interval is 1s
Sleep connection current（Default）
-
259.1
-
Unit：uA. Connection interval is 1s
Main parameter
Description
Note
Reference distance
75m（0dBm）
Clear and open environment, height 1.5m (only 75m can be tested
by the host)
Transmission length
128Byte
Bluetooth protocol
BLE5.0
Communication interface
UART
Package
SMD
Interface
1.27 mm
Size
17.5*28.7mm
Antenna
PCB
50Ω Impedance

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3. Size and pin definition
Pin No.
Name
Direction
Function
1
GND
Ground, connected to power supply reference ground
2
GND
Ground, connected to power supply reference ground
3
GND
Ground, connected to power supply reference ground
4
DIO_0
Input/Output
General IO port, sensor controller (see CC26xx manual for details)
reserved
5
DIO_1
Input/Output
General IO port, sensor controller (see CC26xx manual for details)
reserved
6
DIO_2
Input/Output
RX
7
DIO_3
Input/Output
TX
8
DIO_4
Input/Output
OUT GPIO0
9
DIO_5
Input/Output
OUT GPIO1
10
DIO_6
Input/Output
OUT GPIO2

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11
DIO_7
Input/Output
OUT GPIO3
12
DIO_8
Input/Output
PWM0
13
DIO_9
Input/Output
PWM1
14
DIO_10
Input/Output
PWM2
15
DIO_11
Input/Output
PWM3
16
DIO_12
Input/Output
WAKEUP/SLEEP（Wake up sleep）
17
DIO_13
Input/Output
MODE（Mode selection）
18
DIO_14
Input/Output
DATA（(Data indication）
19
DIO_15
Input/Output
LINK（Connection indication）
20
JTAG_TMS20
Input/Output
JTAG_TMSC, High drive capability (see CC26xx manual for details)
21
JTAG_TCK
Input/Output
JTAG_TCKC, High drive capability (see CC26xx manual for details)
22
DIO_16
Input/Output
High drive general IO port, JTAG_TDO (see CC26xx manual for details)
23
DIO_17
Input/Output
High drive general IO port, JTAG_TDI (see CC26xx manual for details)
24
DIO_18
Input/Output
General IO port，(see CC26xx manual for details) reserved（Baseboard
button）
25
DIO_19
Input/Output
INGPIO0
26
DIO_20
Input/Output
INGPIO1
27
GND
Ground, connected to power supply reference ground
28
DIO_21
Input/Output
INGPIO2
29
VCC
Power supply, 1.8～3.8V
30
DIO_22
Input/Output
INGPIO3
31
DIO_23
Input/Output
ADC0
32
nRESET
Input/Output
Reset, low (see CC26xx manual for details)
33
DIO_24
Input/Output
ADC1
34
DIO_25
Input/Output
Battery voltage acquisition
35
DIO_26
Input/Output
General IO port, sensor controller, digital (see CC26xx manual for details)
reserved
36
DIO_27
Input/Output
General IO port, sensor controller, digital (see CC26xx manual for details)
reserved
37
DIO_28
Input/Output
General IO port, sensor controller, digital (see CC26xx manual for details)
reserved
38
DIO_29
Input/Output
General IO port, sensor controller, digital (see CC26xx manual for details)
reserved
39
DIO_30
Input/Output
General IO port, sensor controller, digital (see CC26xx manual for details)
reserved
40
GND
Ground, connected to power supply reference ground
41
GND
Ground, connected to power supply reference ground
42
GND
Ground, connected to power supply reference ground

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4. Recommended connection diagram
Note: The sensor refers to connecting an external device to a pin with an input function, the peripheral device refers to
connecting an external device to a pin with an output function, and the MODE and WAKEUP / SLEEP pins refer to The
two control pins are connected to the corresponding level state. If the module needs to be woken up, the WAKEUP /
SLEEP (DIO_12) pin should be connected to a low level, or a falling edge signal should be given to the pin in time. If
you need to switch between AT configuration mode and transparent transmission mode, you need to give the
corresponding edge of the MODE (DIO_13) pin.
5. Function description
5.1 Power mode
5.1.0 Low power consumption mode
Power mode refers to the different operations of WAKEUP / SLEEP (DIO_12). The working state (power consumption)
of the module will change differently. The rising edge enters low power consumption mode, and the falling edge enters
wake mode.
About the WAKEUP / SLEEP (DIO_12) pin operation description here: 1), the pin detects the edge signal; 2), the pin has

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an edge latch function, that is, the level of the pin will change with the external edge . For example, the pin initialization
defaults to high level (low power consumption mode). In the future, the pin can only detect the falling edge signal. If the
module wakes up after detecting the falling edge signal, the pin becomes low at this time, and only the rising edge can be
detected. Edge signal; 3). The above-mentioned high-level and low-level during power-on means that the pin needs to be
kept in the high-level or low-level state from the moment of power-on to the normal initialization of the module.
5.1.1 Low power consumption mode
The low power consumption mode means that the BLE function continues to run after the module enters this mode,
and the peripherals of the module except the wake-up pin and the indication function pin are turned off, such as PWM
and IO output. If a lower power consumption setting is required, the AT command can be used to close the broadcast,
disconnect, set a longer broadcast interval and connection interval to achieve the purpose.
There are two ways to enter low power consumption mode: command entry and pin entry.
1. The AT command sends "AT + SLEEP" to immediately enter the low power consumption mode;
2. Enter low power consumption by keeping the rising edge of the WAKEUP pin at over 100ms
The module will actively detect the WAKEUP / SLEEP (DIO_12) pin when it is powered on. If it is high, it will
directly enter the low power consumption (SLEEP) mode after power on, if it is low, it will enter the wakeup
(WAKEUP) mode. The WAKEUP / SLEEP (DIO_12) pin is initialized to a high level by default. If no operation is
performed on this pin, the module powers on and enters the low power consumption (SLEEP) mode.
After the module enters the low power consumption mode, if LOGMSG is turned on, it will output: sleep. During
the low power consumption mode, if the broadcast is turned on, the broadcast will continue, and if the device is
connected, the connection will not be disconnected. After receiving BLE Bluetooth data during the connection, it
will actively wake up the device and print the received data, after printing, continue to enter the low power
consumption mode. If data needs to be sent during low power consumption, you need to give the WAKEUP pin a
falling edge level that lasts for more than 100ms, and wake up the device before sending data.
5.1.2 Wake-up mode
Wake-up mode refers to the normal operation of the module's peripherals, which remain active and do not close the
serial port. At this time, the module continuously receives serial port data, and the power consumption is high. If the
device needs to wake up in low power consumption mode, giving the WAKEUP pin a falling edge that lasts longer than
100ms, and the module is woken up. After waking up, if LOGMSG is turned on, it will output: wakeup.
Note: When using AT configuration and data transparent transmission, the module must be in wake-up mode.
Otherwise, the module cannot receive the data from the serial port (TX) pin.
5.2 Data valid indication
In the transparent transmission mode, after Bluetooth receives the data, it is transmitted transparently through the
serial port. In order to ensure that the external MCU can receive the data correctly, users can set the delayed output data
through the "AT + DELAYDATA = 1" command. After setting, the module's DATA pin will output a low level 10ms

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before sending data to wake up the external MCU. After 10ms, the data starts to be sent, and the DATA pin is pulled high.
as shown in the picture below:
5.3 GPIO Level reading
The E104-BT51 module has four IO read pins. For some places where switch value need to be collected, the level
value of the pin can be queried through the AT command "AT + READGPIO?", this function extends the acquisition
mode of the module. Users do not need to add an additional MCU when collecting signals. They can directly collect
signals through the module, which saves users more resources and reduces the amount of user code development. It is
convenient and quick to use. To read GPIO level, refer to AT command 6.40 Read IO input.
5.4 GPIO Level output
The E104-BT51 module has four IO output pins. For some places where level signal control is needed, the GPIO
level status can be set by the AT command "AT + OUTGPIO = [para]". Users can use the E104-BT51 module as the
controller to control some devices, and the device can be controlled directly through the module without adding an
additional MCU, which saves users more resources and reduces the amount of user code development. It is convenient
and quick to use. To set the GPIOG output, refer to command 6.41 setting and read IO output.
5.5 PWM Output
The E104-BT51 module considers the comprehensiveness of the user's use, and the level control mode may not
meet the requirements and can not realize precise control in some occasions. Therefore, the E104-BT51 module has 4
PWM output pins. Users can set the PWM cycle and duty cycle to achieve the control purpose according their needs. Set
the PWMx enable via AT command “AT + PWMx = 1”, set the period (frequency) of PWMx via AT command “AT +
PERIODx = [para]”, and set the duty cycle of PWMx via AT command “AT + DUTYx = [para]”. The unit of duty
cycle and period (frequency) is us, so you need to pay attention that the duty cycle should not be greater than the period
when using it. After changing the PWM frequency, the duty cycle needs to be set again according to the specific value.
When users use the E104-BT51 module for PWM control, they can directly control the PWM waveform through the
module output without adding an additional MCU, which saves users more resources and reduces the amount of user
code development. It is convenient and quick to use. For details on setting the PWM enable, refer to 6.42 Setting and
reading the PWM Enable. For details on setting the PWM output period, refer to 6.43 Setting and querying the PWM
output period. For details on setting the PWM output duty cycle, refer to 6.44 Setting and querying the PWM duty.
Send AT command: AT + PWM0 = 1, open PWM0 baud rate, output PWM square wave with default period of
100us and duty cycle of 50us.

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5.6 ADC Acquisition
The E104-BT51 module, in order to adapt to a wider range of data acquisition, adds two 12-bit precision ADC
acquisition channels, the reference voltage is fixed ref is 4.3V, uses the command "AT + ADCx?" to read the ADC value
of the ADCx pin and display it in decimal. User can calculate the voltage Vx to be measured according to the formula.
Formula: ref / 4096 = Vx / ADC. For details on reading the ADC acquisition volume, refer to Command 6.45 Querying
the ADC Sample Value.
Notice: This module does not need to do voltage division or other operations, just connect the target to be tested to the
detection pins (DIO_23, DIO_24), and then ground the module.
5.7 Battery voltage service
The E104-BT51 module in order to enable the battery voltage to be obtained in a timely manner, and can be
displayed intuitively in mobile phones or other devices, this module adds a battery voltage service. You only need to
connect a specific ADC acquisition pin to the corresponding battery pin, the device will automatically collect battery
voltage data periodically, calculate the corresponding percentage according to the user's preset voltage upper and lower
limits, and update to the Bluetooth service in real time to wait for other host devices to obtain data. Users can calculate
the corresponding voltage value based on the ratio updated by the Bluetooth service. We use p to represent the
percentage of battery service, Btmax to represent the set full battery voltage, and Btmin to represent the minimum battery

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voltage, in order to make the calculation more accurate, mV is used as the unit, that is, 3.2v voltage value is converted to
3200 to participate in the calculation. The voltage / ratio characteristic curve is shown below. Calculation formula: p = (v
– Btmin) / (Btmax-Btmin). The actual voltage value can be calculated according to the p-in formula of the battery. (Note:
Btmax and Btmin are the values set by AT. Here 3200 and 2000 are just examples.) For details on setting Btmax and
Btmin, refer to the command 6.46 Setting, reading the maximum battery voltage, 6.47 Setting, and querying the
minimum battery voltage.
Note: This module does not need to do voltage division or other operations, just connect the positive electrode of the
battery to the detection pin (DIO_25), and then ground the module.
5.8 MAC Address binding
The E104-BT51 module supports MAC binding function. When the slave module sets the binding connection
address and enables binding, it retrieves whether the host MAC address is a binding address before accepting the host
connection request. When the address matches successfully, the connection can be established, otherwise the slave will
continue to broadcast. For details on setting command, refer to 6.25 Reading MAC Binding Status, and enabling and
disabling MAC binding. For details on setting the binding address, refer to 6.26 Reading and Setting MAC Binding.

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5.9 Bluetooth maximum packet length MTU configuration
MTU is an abbreviation of the communication term Maximum Transmission Unit (MTU), which refers to the
maximum packet size (in bytes) that can be passed on a layer of a communication protocol. This parameter is usually
related to the communication interface (network interface card, serial port, etc.).
The E104-BT51 module supports the long packet standard of Bluetooth 5.0. You can configure the maximum single
packet data length of Bluetooth through the AT command "AT + MTU = xx". 251 bytes by default,27 to 251 bytes
available.Increasing the packet length can realize the large packet data transmission of Bluetooth. For details on setting
command, refer to 6.27 Querying and Setting the MTU Length.
Note: After the packet length is configured, it will take effect on the next Bluetooth connection. Due to some hosts
do not support parameter change requests initiated by slaves, there may be a set MTU length that does not take effect
after connection, which is normal.
5.10 UUID Configuration
The module supports flexible UUID configuration. You can command "AT + UUIDTYPE = 1" to enable the 128-bit
UUID function. You can customize the transparent transmission service UUID, receiving characteristic field UUID,
and sending characteristic field UUID via commands "AT + + SVRUUID = xx", "AT + READUUID = xx", and "AT +
WRITEUUID = xx". UUID, of which xx represents a hexadecimal number. For details on setting method, refer to 6.28
Querying and Setting the UUID Length of the Transparent Transmission Service. This function can solve the problem of
mismatch with UUID of APP communication, meet more custom requirements, and have wider practicability.
5.11 Broadcast data can be switched
The broadcast of the E104-BT51 is divided into general broadcast and iBeacon broadcast. It supports that command
can configure and select the broadcast mode.
General broadcast packet format:
The broadcast information includes advertising and scan respone, advertising is the broadcast message sent actively,
and scan respone is the broadcast message returned after receiving the host scan request.
Advertising：
Fixed field
Len
Vendor field
Manufa data
020106
N
0xFF
Configurable, Max 26 bytes

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Example：0201061AFF4C0002155241444955004E4554574F524B53434F00010002D2
For the content of the set broadcast data, please refer to 6.7 Querying and Setting the General Broadcast Data (save after
power off).
Scan response：
Len
16digit UUID
UUID
Len
Broadcast name
Device name
0x03
0x03
Configurable
N
0x09
Configurable, Max 22 bytes
Example：0303F0FF1009453130342D4254303034
iBeacon Broadcast packet format：
1. The command configures UUID, Major, Minor, and TXPWR respectively
2. The command AT + ADV = 2 is configured to work in iBeacon broadcast mode, and broadcast immediately
3.Bluetooth connection is not supported in iBeacon broadcast mode
Advertising：
iBeacon Prefix
UUID
Major
Minor
TXPWR
9B
16B
2B
2B
1B
Example：0201061AFF4C000215FDA50693A4E24FB1AFCFC6EB076478252775848F00
Because the format of iBeacon broadcast data is fixed, only Majo, Minor, and TXPWR can be modified. For details on
setting iBeacon data, refer to 6.9 Querying and Setting IBeacon Major Broadcast Data.
5.12 Configuration over air
Configuration over air refers to the use of the mobile phone APP program BLE test tool to implement wireless
configuration of the module without using the serial debugging assistant. The E104-BT51 module supports configuration
over air. Our open configuration over air channel is FFF3 under the main service FFF0. The features under this channel
support read, write, and notification. E104-BT51 open some IO port reading, PWM setting and other operations, that is,
users can use configuration over air mode to read the IO status to collect information and cooperate with the PWM
setting to perform some control operations.
Methods for configuration over air:
1. After the slave connection is established, the host (mobile phone app) sends AT commands through the Bluetooth
service feature "CONFIG CHANNEL" to configure module parameters over the air. (The configuration channel of
E104-BT51 is FFF3 under the main service FFF0).
2. "Configuration over air" requires password authentication. The command "AT + AUTH = xxx" sends
authentication information, and the Bluetooth service feature "CONFIG CHANNEL" sends authentication command AT
+ AUTH. After successful authentication, it can enter the configuration status.
3. Authentication succeeds and remains valid until the connection is disconnected.
4. The MOD pin has no effect on the process of configuration over air .
5. Configuration over air is used for all AT commands.

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5.13 Status or event printing
1. The command AT + LOGMSG configures the serial port printing function of status information.
2. Status information includes: connection, disconnection, wake up, and sleep.
The format is as follows:
Status
Printing information
Connection
STA:connection \r\n
Disconnectio
n
STA:disconnection \r\n
Wake up,
wakeup\r\n
Sleep
sleep\r\n
3. Connection command, after the Bluetooth connection is established, the LINK pin outputs a low level, and after the
Bluetooth connection is disconnected, the LINK pin outputs a high level.
5.14 AT configuration
The MODE pin controls the AT configuration mode or transparent transmission mode of the module. During the
connection, the rising edge enters the transparent transmission mode, and the falling edge enters the AT mode.
The module defaults to the AT command mode in the unconnected state. At this time, the serial data will be treated as AT
commands (the module is in the wake-up mode); when the module is connected, if you want to configure AT, you need to
give MODE (DIO_13 ) The pin has a falling edge signal greater than 100ms. After detecting the falling edge, the module
enters AT configuration mode. Serial port data will not be transparently transmitted. It will be treated as an AT command.
After the configuration is completed, the MODE pin will be given a rise greater than 100ms Along the signal, the module
enters the transparent transmission mode.
6. Operation command
Note: Before sending operation commands, first ensure that the module is in wake-up mode, otherwise it will not be
able to receive configuration commands.
1. Instructions:
1.All AT commands do not need to return (\ r), line feed (\ n)
2. The return result of AT instruction ends with \ r \ n
3. The AT command format is "AT + xxx" For example:
Send the command of querying the device name"AT + NAME?"
2.Command return
Return
value
Description
1
Command does not exist
2
Incorrect command length (such as querying the device name: AT + NAME ?, if sent as:

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AT + NAME? 123, the length is incorrect)
3
Invalid parameter (parameter range error)
4
PWM duty cycle is greater than the period
5
PWM cycle range error
6
Configuration over air password authentication failed
7
Change configuration over air Password length error
8
UUID configuration error
9
Unknown mistake
11
AT operation failed
12
Binding MAC address length error
13
Device is disconnected and operation is invalid
14
MAC address is invalid
3、Factory parameter
E104-BT51
Default
parameter
Device name
E104-BT51_V1.0
Broadcast data
CDEBYTE
Configuration over air
password
123456
version No.
V1.0
IBC_Major
1027
IBC_Minor
507
2-byte service UUID
0xF0, 0xFF
16-byte service UUID
0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,
0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
2-byte client UUID1
0xF1, 0xFF
16-byte UUID1
0x01,0x01,0x02,0x03,0x04,0x05,0x06,0x07,
0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
2-byte client UUID2
0xF2, 0xFF
16-byte UUID2
0x02,0x01,0x02,0x03,0x04,0x05,0x06,0x07,
0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
Parity bit
0
Stop bit
1
Baud rate
115200
Broadcast type
General broadcast
TXPWR（RSSI）
0
Broadcast interval
250ms
Maximum connection
interval
40ms
Minimum connection
interval
40ms
Connection timeout
5s
Default UUID type
2 bytes
Transmit power
0dBm

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Status printing
On
MTU length
200
MAC binding enable
Off
MAC binding address
0x01, 0x01, 0x01, 0x01, 0x01, 0xc0
Delay output enable
Off
PWM period
100us
PWM duty cycle
50us
GPIO output
Low level（0）
6.1 AT Command test
Command
Response
Parameter
AT
+OK
No
Description：No
6.2 Read and configure baud rate
Command
Response
Parameter
Query：AT+BAUD?
+OK=[para]
para:0~D
0=1200
1=2400
2=4800
3=9600
4=14400
5=19200
6=28800
7=38400
8=57600
9=76800
A=115200
B=230400
C=460800
D=921600
Setting：AT+BAUD=[para]
+OK：Success
+ERR=[NUM]：Error
Description：Restart to take effect, save when power off
6.3 Read and configure stop bit
Command
Response
Parameter

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Query：AT+STOPB?
+OK=[para]
para:0,1 ASCII
0：1 stop bit
1：2 stop bits
Setting：AT+STOPB=[para]
+OK：Success
+ERR=[NUM]：Error
Description：Restart to take effect, save when power off
6.4 Read and set serial parity
Command
Response
Parameter
Query：AT+?
+OK=[para]
para:0,1,2
0：No parity
1: Even parity
2：Odd parity
Setting：AT+PARI=[para]
+OK：Success
+ERR=[NUM]：Error
Description：Restart to take effect, save when power off
6.5 Set and read serial data length
Command
Response
Parameter
Query：AT+DATALEN?
+OK=[para]
para:2,3
2: Data length 7
3: Data length 8
Setting：AT+DATALEN=[para]
+OK：Success
+ERR=[NUM]：Error
Description：Restart to take effect, save when power off
6.6 Check the current broadcast status, turn on general broadcast, IBeacon
broadcast, turn broadcast
Command
Response
Parameter
Query：AT+ADVEN?
+OK=[para]
para:0、1、2
0：Turn off broadcast
1：General broadcast
2：iBeacon broadcast
Setting：AT+ADVEN=[para]
+OK：Success
+ERR=[NUM]：Error
Description: It takes effect on next broadcast, save when power off
6.7 Query and set general broadcast data (save when power off)
Command
Response
Parameter