EBYTE RS232 Bluetooth Wireless Converter User Manual

The EWD104-BT57 (xxx) is a RS485/RS232 to BLE Bluetooth
converter based on Bluetooth protocol version 5.2. It features
small size, low power consumption, and operates in the 2.4GHz
frequency band. The module uses universal AT commands for easy and
quick operation.

Features

Reliable radio communication
Isolation and high protection for communication port and power
interface

Industrial-grade design with working temperature range of -40°C
to +85°C

Application Scenario

Industrial automation

Security and monitoring applications
Intelligent building and smart city systems

Intelligent robot and Internet of Things applications

Specifications

Limit Parameters

Main parameters	Minimum	Maximum	Remark
Supply voltage (V)	0	28	Exceeding 28V may permanently burn out the module
Operating temperature (°C)	-40	+85

Working Parameters

Main parameters	Minimum	Typical Value	Maximum	Remark
Operating voltage (V)	5	12	28
Operating temperature (°C)	-40		+85

Product Usage Instructions

Frequently Asked Questions (FAQ)

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Chengdu Ebyte Electronic Technology Co., Ltd. E28-2G4M12S Product Specifications
User Manual EWD104-BT57(xxx)
RS485/RS232 to BLE5.2 Bluetooth Wireless Converter
Copyright © 201220 20 , Chengdu Ebyte Electronic Technology Co., Ltd.

Chengdu Ebyte Electronic Technology Co., Ltd.

EWD104-BT57(XXX) User Manual

Table of Contents
RS485/RS232 to BLE5.2 Bluetooth Wireless Converter ……………………………………………………………………………….. 1 Disclaimer and Copyright Notice ……………………………………………………………………………………………………………….. 1 1. Overview …………………………………………………………………………………………………………………………………………….. 2
1.1 Introduction ………………………………………………………………………………………………………………………………… 2 1.2 Features………………………………………………………………………………………………………………………………………. 2 1.3 Application Scenario…………………………………………………………………………………………………………………….. 3 2 Specifications ……………………………………………………………………………………………………………………………………….. 4 2.1 Limit parameters ………………………………………………………………………………………………………………………….. 4 2.2 Working Parameters……………………………………………………………………………………………………………………… 4 3 Mechanical dimensions and pin definition ………………………………………………………………………………………………… 6 4 Functional Description …………………………………………………………………………………………………………………………… 9 4.1 Role Description ………………………………………………………………………………………………………………………….. 9 4.2 Default broadcast data ………………………………………………………………………………………………………………….. 9 4.3 Beacon default configuration…………………………………………………………………………………………………………. 9 4.4 The default configuration of the slave role …………………………………………………………………………………….. 10 4.5 Module status…………………………………………………………………………………………………………………………….. 10 4.6 Configuration…………………………………………………………………………………………………………………………….. 10 4.7 Configuration Mode …………………………………………………………………………………………………………………… 11 4.8 MTU ………………………………………………………………………………………………………………………………………… 11 4.9 Compatibility with other modules of our company …………………………………………………………………………. 11 5 AT Commands …………………………………………………………………………………………………………………………………….. 12 5.1 Instruction Description ……………………………………………………………………………………………………………….. 12 5.2 Error Code ………………………………………………………………………………………………………………………………… 13 5.3 Instruction List…………………………………………………………………………………………………………………………… 13 6 Mobile APP Test, Transparent Transmission ……………………………………………………………………………………………. 26 7 Hardware Design …………………………………………………………………………………………………………………………………. 29 8 Frequently Asked Questions ………………………………………………………………………………………………………………….. 29 8.1 The transmission distance is not ideal …………………………………………………………………………………………… 29 8.2 Modules are vulnerable to damage ……………………………………………………………………………………………….. 30 8.3 The bit error rate is too high ………………………………………………………………………………………………………… 30 9 Ebyte Bluetooth Models ……………………………………………………………………………………………………………………….. 31 Revision History …………………………………………………………………………………………………………………………………….. 32

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EWD104-BT57(XXX) User Manual

Disclaimer and Copyright Notice

The information in this document, including URL references, is subject to change without notice. The document is provided “as is” without warranty of any kind, including any warranty of merchantability, fitness for a particular purpose, or non-infringement, and any warranty otherwise provided by any proposal, specification, or sample. No liability whatsoever is implied with respect to this document, including liability for infringement of any patent arising from the use of the information in this document. This document is not hereby disclaimed as a prohibition of reproduction, No license, express or implied, to any intellectual property rights is granted by word of mouth or otherwise.
The test data obtained in this article are all obtained by Ebyte Laboratory testing, and the actual results may be slightly different.
All trade names, trademarks and registered trademarks mentioned herein are the property of their respective owners and are hereby acknowledged.
The final right of interpretation belongs to Chengdu Ebyte Electronic Technology Co., Ltd.
Notice :
Due to product version upgrades or other reasons, the contents of this manual may be changed. Ebyte Electronic Technology Co., Ltd. reserves the right to modify the contents of this manual without any notice or reminder. This manual is only used as a guide. Chengdu Ebyte Electronic Technology Co., Ltd. tries its best to provide accurate information in this manual, but Chengdu Ebyte Electronic Technology Co., Ltd. does not ensure that the contents of the manual are completely error-free, and all statements, information and suggestions in this manual do not constitute any express or implied warranty.

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1. Overview

EWD104-BT57(XXX) User Manual

1.1 Introduction
EWD104-BT57 (xxx) is a RS485/RS232 to BLE Bluetooth converter based on Bluetooth protocol version 5.2 . It has small size, low power consumption, and works in the 2.4GHz frequency band. The module uses universal AT commands and is easy and quick to operate.
EWD104-BT57 (xxx) can be widely used in home automation, home security, personal health care, smart home appliances, accessories and remote controls, automobiles, lighting, industrial Internet, intelligent data acquisition, intelligent control and other fields.

EWD104-BT57(485)

EWD104-BT57(232)

1.2 Features

Support Bluetooth BLE 5.2 protocol ; Standard RS485/RS232 interface; Easy to use, no Bluetooth protocol application experience required; Support BLE master role, slave role , master-slave integration and Beacon role; The default connection interval is 20ms, which allows fast connection and is compatible with other BLE modules of our company. Support RS485/RS232 or mobile phone APP to send AT commands; Support AT command software reset module ; Support AT command to set the connection interval to control different forwarding rates and adjust dynamic power consumption; Support AT commands to set transmission power, broadcast interval, broadcast name, etc. For details, please refer to 5 AT Commands; Support AT command to modify the slave role Service UUID; Support custom broadcast data from roles; Compatible with other models of modules of our company; Adopt flame-retardant plastic shell and guide rail installation structure, which is convenient and efficient to install; Multiple protection functions such as power reverse connection protection and antenna surge protection greatly increase the

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EWD104-BT57(XXX) User Manual

reliability of the radio; The communication port and power interface adopt isolation and high protection; Working temperature range: -40+85, adaptable to various harsh working environments, a true industrial-grade product;

1.3 Application Scenario

Industrial automation; Security, monitoring applications; Intelligent building; Smart city; Intelligent robot;
Internet of Things applications.

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2 Specifications

EWD104-BT57(XXX) User Manual

2.1 Limit parameters

Main parameters
Supply voltage (V) Blocking power (dBm) Operating temperature ( )

performance

Minimum Maximum

–

-40

+ 85

Remark
Exceeding 28 V may permanently burn out the module The probability of burning is lower when used at close range
Industrial Grade

2.2 Working Parameters

Main parameters

Performance Description

Minimu m

Typical Value

Maximu m

Operating voltage (V)

Operating frequency band (MHz)
Transmit power
Power Emission current (mA) consumpt
Receive current (mA) ion
Receiving sensitivity (dBm) Operating temperature ( )

2400 -20
-40

20
80 5 -95dBm –

2480 twenty three
–
–
+ 85

Remark
5.0 V can guarantee output power , exceeding 28 V may permanently burn the module Support ISM band Peak transient current @ 23 dBm Industrial-grade design

Main parameters Reference distance

describe 600 m

Bluetooth Protocol EWD104-BT57(485) communication
interface EWD104-BT57(232) communication
interface Dimensions RF Interface Hardware Interface Product Weight

BLE 5.2 RS485
RS232
102*28*27 mm SMA-K
Spring type terminal 31g

Remark Clear and open environment, height 2 meters, 23 dBm,
airspeed 1Mbps –
–
±0.2mm Equivalent impedance is about 50
4Pin 3.81mm pitch ±2g

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EWD104-BT57(XXX) User Manual

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3 Mechanical dimensions and pin definition
size:

EWD104-BT57(XXX) User Manual

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EWD104-BT57(485) pin definition:

EWD104-BT57(XXX) User Manual

Serial number 1 2
3
4
5 6 7 8
9

name PWR TXD
RXD
LINK
A B +
ANT

Function Power indicator Send indicator
light Receiving indicator Connection status indicator RS485_A RS485_ B
GND VCC
RF Interface

Remark Blue, always on after power on
Red, data sending indicator
Yellow, data receiving indicator
Green, connection status indicator, always on after connection
RS485 Signal A RS485 signal B Negative pole of power supply Power positive pole, supports DC 5~28V power
supply SMA-K, external threaded inner hole.

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EWD104-BT57(232) pin definition:

EWD104-BT57(XXX) User Manual

Serial number 1 2
3
4
5 6 7 8
9

name PWR TXD
RXD
LINK
T R +
ANT

Function Power indicator Send indicator
light Receiving indicator Connection status indicator
TXD RxD GND VCC
RF Interface

Remark Blue, always on after power on
Red, data sending indicator
Yellow, data receiving indicator
Green, connection status indicator, always on after connection
RS232 Output RS232 Input Negative pole of power supply Power positive pole, supports DC 5~28V power
supply SMA-K, external threaded inner hole.

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EWD104-BT57(XXX) User Manual

4 Functional Description

4.1 Role Description
The module supports the following 4 roles 1. Slave role; 2. Master role; 3. Slave and master roles; 4. Beacon role ;
The factory default is slave role. Switch the role through AT command “AT+ROLE”. For details, see 4 !
4.2 Default broadcast data

As shown in the figure above, data with lengths of 2, 8, and 3 are broadcast data, which respectively represent the type of broadcast information, MAC address information, and UUID information; data with a length of 13 is the data of the scan response packet, which represents the broadcast name (the last 4 bytes are the last two bytes of the MAC address).
4.3 Beacon default configuration
1. Company ID:0x4C00 2. Major UUID:0x2775 3. Minor UUID:0x848F 4. RSSI: -48 dBm 5. UUID:0xFDA50693A4E24FB1AFCFC6EB07647825

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4.4 The default configuration of the slave role

EWD104-BT57(XXX) User Manual

1. Device name: CDEBYTE_XXXX (XXXX is the last two bytes of the module MAC address); 2. Broadcast interval: 200ms; 3. Connection interval 20ms~40ms; 4. The broadcast type is connectable and scannable broadcast; 5. Connection timeout 1 second; 6. UUID defaults to 16 bits;

4.5 Module status

1. MODULE POWERUP: module startup; 2. XX:XX:XX:XX:XX:XX CONNECTD P*X: Connection to the slave succeeded; 3. XX:XX:XX:XX:XX:XX DISCONNECTED P: disconnected from the slave role; 4. XX:XX:XX:XX:XX:XX CONNECTED B: Beacon connected successfully; 5. XX:XX:XX:XX:XX:XX DISCONNECTED B: Beacon is disconnected; 6. XX:XX:XX:XX:XX:XX CONNECTD C*Y: The master role is connected successfully; 7. XX:XX:XX:XX:XX:XX DISCONNECTED C: The primary role is disconnected; 8. ALREADY CONNECTED: This device is already connected; 9. XX:XX:XX:XX:XX:XX CONNECT TIMEOUT: BLE host connection to slave device timed out; The above status can be turned on or off through the AT command “AT+ LOGMSG”, see 5 AT Commands for details.

4.6 Configuration

1A slave device can be connected to at most one master device at the same time . A master device can be connected to at most one slave device at the same time. A master-slave device can be connected to at most one slave device at the same time, and can be connected to at most one master device as a slave device .
2AT+CONNECT command failed to connect to the device prompt + ERR=3, please refer to the command description for the reason ;
3Multi-connection specifies multiple devices to automatically reconnect. When a peer device abnormally disconnects, the module will start automatic reconnection. Please refer to the instruction description ;
4CONNECTED P * X” or through the command AT+CONNECT_LIST ? Get ) ; 5If the user uses a command to actively disconnect from a device that has been set to automatically reconnect, the automatic reconnection will be invalid and will take effect after the next abnormal disconnection .

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4.7 Configuration Mode

EWD104-BT57(XXX) User Manual

The module supports two configuration methods: serial port configuration and APP configuration. APP configuration, that is, using the BLE APP on the mobile phone to configure the module, must first pass the AT+AUTH verification password, some instructions do not support APP configuration completion, see 5.3 Instruction Table for details, only after verification is passed can other AT commands be used. The APP configuration authentication cycle is for this connection. If the device is disconnected and reconnected, re-authentication is required. In configuration mode, when the serial port sends an AT command, you should wait for the serial port to return before sending the next AT command.

4.8 MTU

MTU is the length of a single BLE packet. The default maximum value is 247, and the maximum length of the payload is 244.

4.9 Compatibility with other modules of our company

When other modules of our company are connected to E WM 104-BT5 7U/UP , please pay attention to the big and small end issues when entering the MAC address of E WM 104-BT5 7U/UP .

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5 AT Commands

EWD104-BT57(XXX) User Manual

Note: Before sending operation instructions, first ensure that the module is in AT mode, otherwise it will not be able to receive configuration instructions.
5.1 Instruction Description

Instruction Type Query command

Instruction Format AT+[X]?

describe This command is used to query the parameters of the setting command.

Setting Instructions

AT+[X]=<…>

This command is used to set user-defined parameters.

Execute Instructions

AT+[X]

Used for instructions without parameters, such as module reset.

Notice: Serial port configurations all end with a carriage return (r) and a line feed (n) (APP configurations do not have carriage returns and line feeds); The return results of the two configuration modes end with (r) and (n), which will not be explained later; The default serial port baud rate is 115200, 8 data bits, 1 stop bit, no parity; The command parameters are all in ASCII format; Command error response format +ERR:[NUM], [NUM] see ! In AT commands, <> indicates optional parameters, and [] indicates required parameters. If all parameters of an AT command are optional, any one parameter should be filled in, for example, AT+ADV=,,20. The command part is not case-sensitive (excluding the “APP configuration authentication” command); The module can be configured using the APP when it is in configuration mode or transparent transmission mode; Some commands do not support APP configuration completion, such as “Set extended broadcast”, “AT command to send data”, “Master role scanning”, “Open observer” and other AT commands that require serial port cooperation; All AT commands cannot contain invisible characters such as spaces and tabs.

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5.2 Error Code

EWD104-BT57(XXX) User Manual

N UM
1 2 3
4

illustrate

Cause

Workaround

Instruction does not exist
Parameter error
Operation not allowed or operation
failed
Operational Error

Input command error
Input parameter error Failed to execute related functions (connection, parameter setting, etc.). If the module is powered on and the AT+SCAN command is not executed, execute AT+CONNECT=0.
The current character does not support this command.

Read !6.3 command table, such as setting broadcast parameters, and comparing the command “AT+ADV” character by character to prevent incorrect characters from being entered due to typing or word spelling.
Check !.
The parameters may have been saved, please try again or check the “Description” of each
instruction table in 3.3 Instruction Table
Check !Instruction table

5.3 Instruction List

5.3.1 Test instructions

instruction

answer

+OK

Description: Used to test whether the serial port communication is normal.

5.3.2 Broadcast Name

Query set up parameter illustrate
Example

instruction

answer

AT+NAME?

+ NAME =[para]

AT+NAME=[para]

+OK: Success +ERR=[NUM]: Error

Broadcast Name

immediately and restart to take effect ;

The length of the broadcast name shall not exceed 16 bytes;

The factory default broadcast name is CDEBYTE_XXXX, where XXXX is the last two bytes of the MAC address.

Query the broadcast name (MAC is 2C:11:65:22:B1:1B)

Command: AT+NAME?

Return: +NAME=CDEBYTE_B11B

Set the broadcast name to MY_TEST

Command: AT+NAME=MY_TEST

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Return: +OK

EWD104-BT57(XXX) User Manual

5.3.3 MAC address

Query parameter illustrate
Example

instruction

answer

AT+MAC?

+ MAC =[para]

MAC Address

The returned MAC address is in hexadecimal format.

Assume the local MAC address is 2C:11:65:22:B1:1B

Command: AT+MAC?

Return: +MAC=2C:11:65:22:B1:1B

5.3.4 Module roles

Query parameter parameter illustrate Example

instruction AT+ROLE?
AT+ROLE=[para] para 0 1

answer +ROLE=[para] +OK: Success +ERR=[NUM]: Error
Role slave, from (default)
master

slave and master

Beacon

immediately and restart to take effect ;

Switching roles will clear the auto-reconnect device list;

Query module roles

Command: AT+ROLE?

Return: +ROLE=0

Set the module role to host

Command: AT+ROLE=1

Return: +OK

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5.3.5 Transmit power

EWD104-BT57(XXX) User Manual

Query set up parameter illustrate
Example

instruction

answer

AT+ PWR?

+ PWR =[para]

AT+ PWR =[para]

+OK: Success +ERR=[NUM]: Error

The possible values are 3 , 8 , 12 , 14 , 17, 20 , 21 , 22 , 23

immediately and restart to take effect ;

The actual power may differ slightly from the requested value;

The maximum transmit power is 23 dBm , the default is 20 dBm

Query the transmit power

Command: AT+PWR?

Return: +PWR=0

Set the module transmit power to 3 dBm

Command: AT+PWR= 3

Return: +OK

5.3.6 Broadcast parameters

Query set up parameter illustrate
Example

instruction

answer

AT+ADV?

+ ADV =[para1],[para2],[para3]

AT+ADV=<para1>,<para2>,<para3>

+OK: Success +ERR=[NUM]: Error

para1

Broadcast status: 0, off; 1, on;

para2

Broadcast Type: 0, broadcast cannot be connected; 1, broadcast can be connected

para3

Broadcast interval, range 20~10240, default 200ms

immediately and restart to take effect ;

This setting is only supported in slave roles (including slave, master-slave integration, and beacon). It is not

supported in the master role.

Query broadcast parameters

Command: AT+ADV?

Return: +ADV=1,1,200

Set to enable unconnectable broadcast and broadcast at intervals of 500ms

Command: AT+ADV=1,0,500 or AT+ADV=,0,500 (when broadcasting is turned on)

Return: +OK

Disable broadcasting (other two parameters remain unchanged)

Command: AT+ADV=0,0,500 or AT+ADV=0

Return: +OK

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5.3.7 Customized broadcast data

EWD104-BT57(XXX) User Manual

Query set up set up (Not Saved) parameter
illustrate
Example

instruction AT+ADVDATA?
AT+ADVDATA=[para], <para2>
AT+ADVDATA_CUR=[para], <para2>

answer + ADVDATA =[para1],[para2] +OK: Success +ERR=[NUM]: Error

para1: data input format (0: ASCII; 1: HEX) para2: Custom broadcast data
Save immediately and restart to take effect; If no custom broadcast data has been set, NULL is returned; Only the slave role and the master-slave role support this command. The master role and the Beacon role do not
support this command. This data is placed in the manufacturer’s custom field, and users can customize up to 26 bytes; Use the command “AT+ADVDATA=0” or “AT+ADVDATA=1” to restore the broadcast data to the default
broadcast data; The APP configuration completion setting function is not supported.
Set the broadcast data to: ebyte Command:AT+ADVDATA=ebyte
Return:+OK Set the broadcast data to: 0x55 0x66 0x77 0x88 0x99
Command:AT+ADVDATA=1,5566778899 Return:+OK

5.3.8 Beacon parameters

Query set up
parameter illustrate
Example

instruction

answer

AT+BEACON?

+ BEACON =[para1], [para2], [para3], [para4], [para5]

AT+ BEACON =<para1>, <para2>,

+OK: Success

+ERR=[NUM]: Error

para1: company ID, default 0x4C00

para2: Major UUID, default 0x2775

Para3: Minor UUID, default 0x848F

Para4: 1 meter distance reference rssi, default -48, range -90~-10

Para5: Custom UUID, default is 0XFDA50693A4E24FB1AFCFC6EB07647825

Save immediately and restart to take effect;

Query Beacon Parameters

Command:AT+BEACON?

Return: +BEACON=4C00,2775,848F,-48,FDA50693A4E24FB1AFCFC6EB07647825

Setting Beacon Parameters

Command: AT+BEACON=4C00,0102,0304,-48,FDA50693A4E24FB1AFCFC6EB07647825

Return:+OK

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5.3.9 From Role Services

EWD104-BT57(XXX) User Manual

Query set up parameter illustrate
Example

instruction

answer

AT+SERVICE?

+ SERVICE =<para1>, <para2>, <para3>, <para4>, <para5>, <para6>

AT+ SERVICE=<para1>, <para2>, <para3>,

+OK: Success

+ERR=[NUM]: Error

para1: UUID number of bits (0: 16 bits; 1: 128 bits)

para2: module server UUID (3rd and 4th bytes), length 4

Para3: module receiving channel UUID (3rd and 4th bytes of 128-bit UUID), length 4

Para4: module sending channel UUID (3rd and 4th bytes of 128-bit UUID), length 4

Para5: Wireless AT command channel UUID (3rd and 4th bytes of 128-bit UUID), length 4

Para6: 128-bit basic UUID (the 3rd and 4th bytes of the basic UUID are replaced with the actual 128-bit

UUID of the UUID module of the above parameters), length 32

Save immediately and restart to take effect;

This command is only effective for slave roles (single slave, master-slave and Beacon);

The base UUID of 0000xxxx-0000-1000-8000-00805F9B34FB is not usable.

Query the default 16-bit slave role service

Command:AT+SERVICE?

Return: +SERVICE=0,FFF0,FFF1,FFF2,FFF3

Set up 128-bit slave role service

Command: AT+SERVICE=1,0001,0002,0003,0004,9ECADC240EE5A9E093F3A3B50000406E

Return:+OK

Query the settings of the 128-bit slave role service

Command:AT+SERVICE?

Return: +SERVICE=1,0001,0002,0003,0004,9ECADC240EE5A9E093F3A3B50000406E

5.3.10 Main Role Scan

Query set up parameter illustrate

instruction

answer

AT+SCAN?

+ SCAN=[para1], [para2], [para3]

+OK: Success

0 02:83:E1:66:C2:D0 -89

AT+ SCAN =[para1], <para2>, <para3>

1 9C:19:C2:39:7D:35 -75

…

+ERR=[NUM]: Error

para1: Current scanning status, 0: Stop; 1: Scanning

para2: Scan timeout, in seconds, value range 1-65535

Para3: Whether to display the Bluetooth name, 0: not display 1: display (default)

immediately and starts scanning, but the parameters are not saved;

This command is only effective for the master role (master, master-slave integration);

The scan will automatically stop when the number of devices reaches 20 or the scan timeout period is

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EWD104-BT57(XXX) User Manual

Example

reached; Query the master role scanning parameters
Command: AT+SCAN? Return: +SCAN=0,20,1 Set the main role scanning parameters (start scanning, do not display Bluetooth name, scan time 20 seconds) Command: AT+SCAN=1,20,0
Return: +OK

5.3.11 Master role connection

set up parameter illustrate
Example

instruction

answer

AT+ CONNECT=<para1>, <para2>

+OK: Success +ERR=[NUM]: Error

para1: Connect to the specified slave device according to the serial number or MAC address in the list

returned by the “AT+SCAN” command;

para2: MAC address.

Take effect immediately;

Connect to the slave device with the specified MAC address. Parameter 1 is omitted and only the MAC

address to be connected is filled in; the connection may time out when connecting to the device, resulting in

a connection failure. The connection timeout is 10 seconds. After the timeout, the prompt is:

“C1:02:03:04:05 CONNECT TIMEOUT”. After the connection is successful, the last number of the status

print prompt string is the handle of the newly established connection, and the current transparent

transmission also points to this handle;

A single master role can connect to at most one slave role device;

When the maximum number of connections is reached, using this command again will return +ERR=3, and

you need to disconnect a connected device before connecting a new device;

3 seconds after printing the connection information , because it takes some time for the host to discover the

service) before initiating the next connection, otherwise it will return +ERR=3.

If the master role exceeds the maximum number of connections or the remote Bluetooth has established a

connection with this module, using this command will directly return +ERR=3.

Connect to the slave device with sequence number 5 in the parameter list returned by the AT+SCAN

command

Command: AT+CONNECT =5

return:

+OK

C1:02:03:04:05 CONNECTD C*1

The connection specifies the MAC address C1:02:03:04:05

Command: AT+ CONNECT=, C1:02:03:04:05

return:

+OK

C1:02:03:04:05 CONNECTD C*1

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5.3.12 Command to send data

EWD104-BT57(XXX) User Manual

set up parameter illustrate
Example

instruction

answer

AT+SEND=[para1],[para2], <para3>

+OK: Success +ERR=[NUM]: Error

para1: connection handle value, range 1~ 4

para2: data length, range 1- 243 bytes

para3: Send data input timeout (range 1~5000, unit ms, the default value is 500ms when the parameter is not

set)

Effective immediately;

In the following example, if the specified length of data is input within the set timeout period, +OK is

returned. If the timeout period expires and the specified input length is not reached, RECEIVE TIMEOUT is

returned.

In AT command mode, if BLE data is received, the prefix “+RECEIVED:” will be printed, followed by the

first parameter of the connection handle value, the second parameter of the received data length, and

“1234567890” is the received data. If it is in transparent transmission mode, the data will be printed directly;

The APP configuration completes the setup function. The APP configuration completes the setup function.

The connection handle is 1, the sent data (ASCII) is ABCED, and the input timeout is 5000ms.

Command: AT+SEND=1,5,5000

return:

+OK

INPUT BLE DATA:10

The module receives BLE data in AT command mode

+RECEIVED:1,10

BLE DATA

1234567890

5.3.14 Display connected devices

Query parameter
illustrate
Example

instruction

answer

AT+CONNECT_LIST?

+ CONNECT_LIST=[para1],[para2]

para1: connection handle

para2: MAC address of the remote device

Effective immediately;

Valid in slave, master, and master-slave roles ;

This command is used together with AT+TRM_HANDLE. For example, AT+TRM_HANDLE=1 means that

the master role transparently transmits data to the device with handle value 1 and MAC address

2C:11:65:22:B0:F1.

The handle value followed by the letter “P” indicates that the connection is a master device (mobile phone or

master role module) in the slave role.

Show connected devices

Command: AT+CONNECT_LIST?

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return: +CNT_LIST= 1P,2C:11:65:22:B0:F1 2,2C:11:65:22:AD:59

EWD104-BT57(XXX) User Manual

5.3.15 Disconnect

set up parameter illustrate
Example

instruction

answer

AT+DISCON=[para1],[para2]

+OK: Success +ERR=[NUM]: Error

para1: Current role, 0: single slave role, 1: single master role, 2: master-slave integration

para2: handle value to be disconnected, you can use AT command “AT+CONNECT_LIST” to query

Effective immediately;

Note: Parameter 2 must be used in the correct role (that is, parameter 1 must be the role of the current device).

If the device is in the master role and has connected two slave role devices, “AT+DISCONNECT=1,1” means

disconnecting the slave role device whose handle is 1 from the master role.

AT+DISCON disconnects all connections.

Disconnect the specified connection

Command: AT+DISCON=1,1

return:

+OK

2C:11:65:22:B0:F1 DISCONNECTD C

Disconnect all current connections of the master role

Command: AT+DISCON

return:

+OK

2C:11:65:22:B0:F1 DISCONNECTD C

7D:C2:A0:35:4C:21 DISCONNECTD P

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5.3.16 Automatic reconnection

EWD104-BT57(XXX) User Manual

Query set up parameter illustrate
Example

instruction

answer

AT+AUTO_CNT?

+ AUTO_CNT =[para1],[para2]

AT+ AUTO_CNT =[para1], <para2>

+OK: Success +ERR=[NUM]: Error

Para1: 0: turn off automatic reconnection, 1: turn on automatic reconnection;

Para2 (optional parameter): Add device MAC to the automatic reconnection list. If this parameter is

included, the automatic reconnection function will be turned off or on according to the setting value of

parameter 1. At the same time, other devices in the automatic reconnection list are not affected by this

command. The default value is NULL.

Save immediately and restart to take effect;

The slave device disconnected by the “AT+DISCON” command will not automatically reconnect this time.

The automatic reconnection function can be restored under the following conditions:

Use the command again to connect to the slave device

Restart module

Query the reconnect device list

Command: AT+AUTO_CNT?

Return: +OK=NULL

Enable automatic reconnection and set the reconnection device MAC C2:01:02:03:04:05

Command: AT+AUTO_CNT=1,C2:01:02:03:04:05

Return: +OK

Enable the automatic reconnection function for all devices in the automatic reconnection list

Command: AT+AUTO_CNT=1

Return: +OK

Disable the automatic reconnection function for the device with MAC C2:01:02:03:04:05

Command: AT+AUTO_CNT=0,C2:01:02:03:04:05

Return: +OK

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5.3.17 Delete automatic reconnection

EWD104-BT57(XXX) User Manual

set up parameter illustrate
Example

instruction

answer

AT+ DEV_DEL=[para]

+OK: Success +ERR=[NUM]: Error

para: MAC address, such as C2:01:02:03:04:05

Save immediately and restart to take effect;

AT+DEV_DEL=ALL deletes all reconnected devices;

Deleting the reconnected device does not affect the current connection status;

The entered MAC address does not exist in the automatic reconnection list, and error code 3 is returned.

Delete the device with MAC address C2:01:02:03:04:05

Command: AT+DEV_DEL=C2:01:02:03:04:05

Return: +OK

Delete all reconnected devices

Command: AT+DEV_DEL=ALL

Return: +OK

5.3.18 Specifying the transmission device

Query set up parameter illustrate
Example

instruction

answer

AT+TRM_HANDLE?

+OK=[para]

AT+ TRM_HANDLE =[para]

+OK: Success +ERR=[NUM]: Error

The assigned handle value ranges from 1 to 4

It takes effect immediately and will not be saved if the power is off. After answering +OK, it will directly

enter the data transparent transmission mode

If you need to exit the data transparent transmission mode, enter the “+++ ” command to re-enter the AT

command mode.

The slave, master, and master-slave roles support this command.

If the handle corresponding to the input parameter does not exist, error code 4 is returned.

Query the current data transparent transmission handle (when there is no connection)

Command: AT+TRM_HANDLE?

Return: +OK=NULL

Set the device handle to 1 to transmit data (use the AT+CONNECT_LIST command to obtain the device

handle value for data transparent transmission)

Command: AT+TRM_HANDLE=1

Return: +OK

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5.3.19 Connection Interval

EWD104-BT57(XXX) User Manual

Query set up parameter illustrate
Example

instruction

answer

AT+CONN_INTERVAL?

+ CONN_INTERVAL =[para]

AT+ CONN_INTERVAL =

+OK: Success

[para]

+ERR=[NUM]: Error

para: connection interval, parameter value range is 6~3200, connection interval = parameter * 1.25, unit is ms.

The default value is 20ms.

Takes effect immediately and is saved after power failure;

When connecting to a mobile phone, the recommended connection interval is no less than 20ms;

The longer the connection interval, the longer the update time;

The larger the connection interval, the slower the data forwarding and the lower the dynamic power

consumption.

Query connection interval

Command: AT+CONN_INTERVAL?

Return: +OK=16

Set the connection interval to 100ms, 100 divided by 1.25 = 80

Command: AT+CONN_INTERVAL=80

Return: +OK

5.3.20 APP configuration authentication

set up parameter illustrate
Example

instruction

answer

AT+AUTH =[para]

+OK: Success +ERR=[NUM]: Error

The length must be 6 characters, 0 to 9, the default is 123456

The single connection is valid and re-authentication is required after reconnection.

After a mobile phone or other device is connected to the module, this command can be sent through the configuration

channel. After a successful return, all AT commands can be used through the configuration channel.

This command is only supported by mobile APP; this command must be capitalized.

APP configuration authentication

Command: AT+AUTH=123456

Return: +0K

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5.3.21 APP configuration authentication password

EWD104-BT57(XXX) User Manual

Query set up parameter illustrate
Example

instruction

answer

AT+UP_AUTH?

+ UP_AUTH =[para]

AT+UP_AUTH =[para]

+OK: Success +ERR=[NUM]: Error

The length is fixed at 6, and the default value is 123456.

Take effect immediately and save after power off;

Only supports serial port configuration.

Query air configuration authentication

Command: AT+UP_AUTH?

Return: +0K=123456

Change the air configuration authentication password

Command: AT+UP_AUTH=392578

Return: +OK

5.3.22 Status Output

Query set up parameter illustrate
Example

instruction

answer

AT+LOGMSG?

+ OK =[para]

AT+LOGMSG =[para]

+OK: Success +ERR=[NUM]: Error

0: Status display off

1: Status display is on (default)

It takes effect immediately and is saved after power failure.

Query the current status output function

Command: AT+LOGMSG?

Return: +OK=1

Set to off state output

Command: AT+LOGMSG=0

Return: +OK

5.3.23 Module soft reset

instruction illustrate

instruction

answer

AT+RESET

+OK

The module software is reset after a delay of 100ms.

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5.3.24 Restore factory settings

EWD104-BT57(XXX) User Manual

instruction illustrate

instruction

answer

AT+RESTORE

+OK

After the setting is completed, the module will reset the software after a delay of 100ms;

During the factory reset process, any form of reset is prohibited, and power off before the operation is

completed is prohibited;

5.3.25 Firmware Version

Query parameter illustrate
Example

instruction

answer

AT+VERSION?

+VERSION=[para]

para: Firmware version number

The last two digits of the firmware version indicate the version number.

Command: AT+VERSION?

Return: +OK=7 508 -0-10

5.3.26 Serial port Baud rate

Query set up parameter illustrate
Example

instruction

answer

AT+BAUD?

+BAUD =[para]

AT+BAUD=[para]

+OK +ERR=[NUM]

para: Serial port Baud rate. Possible values: 1200,2400,4800,9600,14400,19200,38400,57600,115200,230400,460800,921600 115200

Restart effective, power down save.

Query the current serial port baud rate

Instruction: AT+BAUD?

Return: +BAUD=115200

The serial port baud rate is set to 9600

Instruction: AT+BAUD=9600

Return: +OK

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6 Mobile APP Test, Transparent Transmission

EWD104-BT57(XXX) User Manual

The mobile BLE APP can be downloaded from the App Store and the application market. Open the App Store or the application market, search for nRF Connect, download and install it, and then test it. This document takes the iOS version of nRF Connect as an example.

The module is connected to the computer through the USB to serial port tool. If it is equipped with a baseboard, it is directly connected to the computer and the computer port number used is checked (steps: right-click Start->Device Manager->Port in the lower left corner of the win10 desktop).
Open the serial port debugging tool and set the correct port number and baud rate. The factory default serial port parameters of the module are baud rate 115200bps, data bit 8, parity bit none, and stop bit 1.

Open nRF Connect, search for Bluetooth devices with a name starting with CDEBYTE_ and connect. After the connection is successful, Disconnect is displayed in the upper right corner of the phone, indicating that it is connected. Slide the phone interface left and right to see the service list and log information. The computer serial port debugging assistant will print connection information, such as XX:XX:XX:XX:XX:XX CONNECTD P*1. Find the data transmission and configuration Service in the service list, turn on the notify enable of the receiving and configuration commands, and then you can perform data transmission and AT commands with

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the module.

EWD104-BT57(XXX) User Manual

Chengdu Ebyte Electronic Technology Co., Ltd.

EWD104-BT57(XXX) User Manual

Chengdu Ebyte Electronic Technology Co., Ltd.
7 Hardware Design

EWD104-BT57(XXX) User Manual

It is recommended to use a DC regulated power supply to power the module. The power supply ripple coefficient should be as small as possible and the module should be reliably grounded.
Please pay attention to the correct connection of the positive and negative poles of the power supply. Reverse connection may cause permanent damage to the module.
Please check the power supply to ensure that it is within the recommended power supply voltage. If it exceeds the maximum value, the module will be permanently damaged.
Please check the stability of the power supply. The voltage should not fluctuate greatly or frequently. When designing the power supply circuit for the module, it is often recommended to retain more than 30% margin, which is
conducive to long-term stable operation of the whole machine; The module should be kept as far away as possible from parts with large electromagnetic interference, such as power supplies,
transformers, and high-frequency wiring; If there are devices with large electromagnetic interference around the module, it will also greatly affect the performance of the
module. It is recommended to keep them away from the module according to the intensity of the interference. If possible, appropriate isolation and shielding can be performed. If there are traces with large electromagnetic interference around the module (high-frequency digital, high-frequency analog, power traces), it will also greatly affect the performance of the module. It is recommended to keep them away from the module according to the intensity of the interference. If possible, appropriate isolation and shielding can be performed. Try to stay away from some TTL protocols whose physical layer is also 2.4GHz, such as USB3.0; The antenna installation structure has a great impact on the performance of the module. Make sure the antenna is exposed and preferably vertically upward. When the module is installed inside the housing, use a high-quality antenna extension cable to extend the antenna to the outside of the housing; The antenna must not be installed inside a metal shell, as this will greatly reduce the transmission distance.

8 Frequently Asked Questions

8.1 The transmission distance is not ideal
When there is a straight-line communication obstacle, the communication distance will be attenuated accordingly ; Temperature, humidity, and co-channel interference can increase the communication packet loss rate ; The ground absorbs and reflects radio waves, so the test results are poor when close to the ground ; Seawater has a strong ability to absorb radio waves, so the test effect at the seaside is poor ; If there are metal objects near the antenna, or the antenna is placed in a metal shell, the signal attenuation will be very serious ; The power register is set incorrectly, or the air rate is set too high (the higher the air rate, the closer the distance) ; The power supply voltage is lower than the recommended value at room temperature. The lower the voltage, the lower the power
output . The antenna used does not match the module well or the antenna itself has quality issues.

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8.2 Modules are vulnerable to damage

EWD104-BT57(XXX) User Manual

Please check the power supply to ensure that it is within the recommended power supply voltage. If it exceeds the maximum value, the module will be permanently damaged .
Please check the stability of the power supply. The voltage should not fluctuate greatly or frequently . Please ensure anti-static operation during installation and use, as high-frequency components are sensitive to static electricity ; Please ensure that the humidity is not too high during installation and use, as some components are humidity sensitive devices ; If there is no special requirement, it is not recommended to use it at too high or too low temperature.

8.3 The bit error rate is too high

There is interference from the same frequency signal nearby. Stay away from the interference source or change the frequency or channel to avoid interference.
An unsatisfactory power supply may also cause garbled characters, so the reliability of the power supply must be ensured; Extension cables or feeder cables that are of poor quality or are too long can also cause a high bit error rate.

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9 Ebyte Bluetooth Models

EWD104-BT57(XXX) User Manual

Model

Chip

Frequency Hz

E73-2G4M04S1A nRF52810

2.4G

E73-2G4M04S1B nRF52832

2.4G

E73-2G4M08S1C nRF52840

2.4G

E104-BT01

CC2541

2.4G

E104-BT02

DA14580

2.4G

E72-2G4M04S2B C C2640

2.4G

E104-2G4U04A C C2540

2.4G

E104-BT5010A nRF52810

2.4G

TX power dBm
4 4 8 0
0
2 0 0

Communi

BLE

Size

cation

version mm

interface

Antenna type

1 7.5 *

I/O

4.2/5.0

PCB/IPX

28.7

1 7.5 *

I/O

4.2/5.0

PCB/IPX

28.7

I/O

4.2/5.0 1 3 * 18 PCB/IPX

I/O

4.0

14*22

PCB

TTL

4.2

14*22

PCB

TTL

4.2

14*2 3 PCB/IPX

USB

4.0 1 8 * 59

PCB

UART

Ceramic 5.0 1 1.5 * 16
Antenna

Features
Hardware Resources Secondary Development Hardware Resources Secondary Development Hardware Resources Secondary Development Hardware Resources Secondary Development Industry’s lowest power consumption High-speed continuous transmission sniffing Built-in A RM dual core Multi-role
mode Dongle Protocol Analyzer Low power consumption, transparent transmission

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Revision History

Version 1.0 1.1 1.2

Revision Date 2025-01-17 2025-02-06 2025-03-21

Revision Notes Initial release Content revision Added serial port Baud rate A instruction

EWD104-BT57(XXX) User Manual
Maintainer Bin Bin Bin

Contact Us
Hot line:4000 330 990 Technical support: support@cdebyte.com Documents and RF Setting download link: https://www.ru-ebyte.com Thank you for using Ebyte products! Please contact us with any questions or suggestions: info@cdebyte.com Address: B2 Mould Industrial Park, 199# Xiqu Ave, High tech Zone, Chengdu, Sichuan

Documents / Resources

EBYTE RS232 Bluetooth Wireless Converter [pdf] User Manual
EWD104-BT57 xxx, E28-2G4M12S, RS232 Bluetooth Wireless Converter, RS232, Bluetooth Wireless Converter, Wireless Converter, Converter

References

User Manual

EBYTE RS232 Bluetooth Wireless Converter User Manual

RS232 Bluetooth Wireless Converter

Product Specifications

Overview

Features

Application Scenario

Specifications

Limit Parameters

Working Parameters

Product Usage Instructions

Frequently Asked Questions (FAQ)

Documents / Resources

References

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