FSC-BT691 user guide

Introduction

Description

This design guide is suitable for engineers developing FSC-BT691 series Bluetooth modules

Module Default Settings

Name	Feasycom
Service UUID	FFF0
Write UUID	FFF2
Notify UUID	FFF1
UART Baudrate	115200/8/N/1

Hardware Description

Pin Diagram

Pin Description

Pin	Pin Name	Type	Pin Descriptions
1	UART_TX	O	UART data output
2	UART_RX	I	UART data input
6	MODE	I	L=throughput mode ,H=command mode
6	RESET	I	External reset input: Active LOW, with an inter an internal pull-up.
7	VDD	Power	Power supply voltage 3.3V, LDO power supply preferred
8	GND	GND	GND
15	DISCONNECT	I	High-level disconnect (must be connected first)
17	LED	O	Bluetooth not connected output square wave, Bluetooth connection output high level
18	STATUS	O	Bluetooth not connected output low level, Bluetooth connection output high level
20	EXT_ANT	ANT	Changing the 0 ohm resistance near the antenna, it is possible to connect a Bluetooth antenna externally

Hardware Design Notes

The simple test of the module only needs to connect VDD/GND/UART_RX/UART_TX to use
If the MCU needs to obtain the connection status of the Bluetooth module, it needs to be connected to the STATUS pin
After drawing the schematic diagram, please send it to Feasycom for review, so as to prevent the Bluetooth distance from not reaching the best effect

Function Description

GPIO state

MODE PIN is PIN 6

State	Description
Low level	Throughput mode
High level	AT command mode

Note

To use this function, the pin function needs to be enabled using the AT command. Please refer to AT+PIOCFG for more details.

DISCONNECT PIN is PIN 15

tate	Description
Low level	–
High level	disconnected

Note

To use this function, the pin function needs to be enabled using the AT command. Please refer to AT+PIOCFG for more details.

LED PIN is PIN 17

State	Description
1Hz square wave	disconnect state
high level	connected state

Connection status PIN is PIN 18

State	Description
low level	disconnect state
high level	connected state

Mode

Throughput mode	when disconnected, the data received by the serial port is analyzed according to the AT command; when connected, all the data received by the serial port is sent to the remote Bluetooth as it is.
Command mode	when disconnected, the data received by the serial port is analyzed according to the AT command; when connected, The data received by the serial port is still parsed according to the AT command. when it is necessary to send data to the remote end, send AT+LESEND command.

GATT Throughput Service

type	UUID	Permissions	Description
Service	0xFFF0		GATT Throughput Service
Write	0xFFF2	Write，Write Without Response	APP send data to module
Notify	0xFFF1	Notify	Module send data to remote

AT command description

Command description

Throughout this specification:

Content between { } is optional
Content behind << represents a COMMAND from Host
Content behind >> represents a RESPONSE/EVENT to Host

Command

The command is the control command sent by the host to the module actively. After receiving the command, the module needs to reply <CR><LF>OK<CR><LF> as a response.

Command Format

AT+Command{=Param1{,Param2{,Param3…}}}<CR><LF>

All commands start with AT, end with <CR><LF>
<CR> means “carriage return”, corresponds to hex value 0x0D
<LF> means “line feed”, corresponds to hex value 0x0A
If Command has Parameter, Parameter follows behind ‘=’
If Command has multiple Parameters, Parameter must be separated by ‘,’
If Command has Response, Response starts with <CR><LF>, ends with <CR><LF>
The module should always return the result of instruction execution (success returns OK，failure returns ERROR)

Example:
Read module’s name
<< AT+VER
>> +VER=1.0.0,FSC-BT691
>> OK

Write invalid baudrate
<< AT+BAUD=0
>> ERROR

Event

Event is the data that the module actively sends to the host. Generally used to indicate a change of state or data received.

Event Format

<CR><LF>+Indication{=Param1{,Param2{,Param3…}}}<CR><LF>

All Events start with <CR><LF>, end with <CR><LF>
If Event has Parameter, Parameter follow behind ‘=’
If Event has multiple Parameters, Parameter must be separated by ‘,’

Example:
Receive data from APP in command mode
>> +DATA=10,1234567890

Commands Table

AT - Serial communication test

Command	AT
Response	OK
Description	When powering on or changing the baud rate, test the UART communication between the host and the module

Example:
<< AT
>> OK

AT+VER - Get Firmware Version

Command	AT+VER
Response	+VER=Param
`Param`	Firmware version
Description	Get Firmware Version

Example:
<< AT+VER
>> +VER=1.0.0,FSC-BT691
>> OK

AT+ADDR - Get MAC Address

Command	AT+ADDR
Response	+ADDR=Param
`Param`	Module’s MAC address (12 Bytes ASCII)
Description	Get MAC Address

Example:
<< AT+ADDR
>> +ADDR=DC0D30010203
>> OK

AT+NAME - Get/Set Local Name

Command	AT+NAME{=Param1{,Param2}}
`Param1`	local name(1~29 Bytes ASCII)
`Param2`	MAC address suffix(0/1,default:0) 0: Disable suffix 1: Enable suffix “XXXX” (lower 4 bytes of MAC address) after local name
Response	+NAME=Param
`Param`	local name
Description	Write local name if parameter exist, otherwise read current local name

Example:
Read current local name
<< AT+NAME
>> +NAME=Feasycom
>> OK

Change module’s local name to “ABC”
<< AT+NAME=ABC
>> OK

Change module’s local name to “ABC” and enable suffix
<< AT+NAME=ABC,1
>> OK

AT+BAUD - Get/Set Uart Baudrate

Command	AT+BAUD{=Param}
`Param`	baudrate(2400/4800/9600/14400/19200/28800/38400/ 57600/115200/230400/460800/500000/921600/1000000, default:115200)
Response	+BAUD=Param
`Param`	baudrate
Description	Module will change baudrate to target value immediately

Example:
Query baudrate
<< AT+BAUD
>> +BAUD=115200
>> OK

Change baudrate
<< AT+BAUD=9600
>> OK

AT+TXPOWER - Get/Set TX Power

Command	AT+TXPOWER{=Param}
`Param`	tx power(default:3)
Response	+TXPOWER=Param
`Param`	tx power
Description	Get/Set TX Power

Example:
Get tx powe
<< AT+TXPOWER
>> +TXPOWER=3
>> OK

Set tx power to 0dbm
<< AT+TXPOWER=0
>> OK

AT+LPM - Get/Set low power config

Command	AT+LPM{=Param}
`Param`	low power mode (0/1, default: 0) 0: disable 1: enable low power and wake up by UART
Response	+LPM=Param
`Param`	low power mode
Description	Get/Set low power config

Example:
Get low power config
<< AT+LPM
>> +LPM=0
>> OK

Set serial port wakeup mode
<< AT+LPM=1
>> OK

AT+ADVIN - Get/Set advertising interval

Command	AT+ADVIN{=Param}
`Param`	advertising interval (100~10000 ms0 ms, 默认: 687ms)
Response	+ADVIN=Param
`Param`	advertising interval
Description	Get/Set advertising interval

Example:
Get advertising interval
<< AT+ADVIN
>> +ADVIN=687
>> OK

Set advertising interval to 100ms
<< AT+ADVIN=100
>> OK

AT+DISC - Disconnect specified connection

Command	AT+DISC
Response	OK
Description	disconnect Bluetooth connection

Example:
disconnect device
<< AT+LEDISC
>> OK

AT+LECCONN - Initiate a connection to the specified address

Command	AT+LECCONN{=Param1{,Param2{,Param3{,Param4}}}}
`Param1`	12-byte device address + 1-byte address type
`Param2`	Communication Service UUID
`Param3`	Communication UUID with write/write without rsp permission
`Param4`	Communication UUID with notification permission
Response	OK
Description	Initiate a connection to the specified device, the parameter consists of 12 bytes (device address) and 1 byte (address type), generally the address type is “0” or “1”. address How to get the address type: Send AT+SCAN=1 command, get parameter2. example: +SCAN=0,0,DC0D30001ED4,-65,10,FSC-BT946 Connection command: AT+LECCONN=DC0D30001ED40

Example:
Connect to the specified device, 0 is the address type
<< AT+LECCONN=DC0D3000039E0
>> OK

Initiate a connection to the specified address, using FFF0, FFF2, FFF1 for communication
<< AT+LECCONN=DC0D3000039E0,FFF0,FFF2,FFF1
>> OK

AT+SCAN - SCAN for nearby devices

Command	AT+SCAN{=Param1{, Param2{, Param3}}}
`Param1`	scanning method（0~1） 0: stop scanning 1: Scan nearby devices, filter duplicate addresses, up to 8 devices can be found
`Param2`	Scan Timeout Setting(200ms~2s,100 is equal to 1000ms)
`Param3`	Scan Filter Name/MAC (If it’s a 12-digit standardized MAC, filter by MAC; otherwise, filter by name)
Response	+SCAN=Param1,Param2,Param3,Param4,Param5
`Param1`	MAC Address type (1 byte)
`Param2`	MAC address (12 bytes)
`Param3`	RSSI
`Param4`	Device name length
`Param5`	Device name
Description	AT+SCAN=1 Commonly used for searching before connecting

Example:
SCAN device
<< AT+SCAN=1
>> +SCAN={
>> +SCAN=1,70CFC9A98840,-43,24,LE-Bose QuietControl 30
>> +SCAN=1,DC0D30001ED4,-65,10,FSC-BT946
>> +SCAN=}

Set a 5-second timeout and filter devices with “BT618” in their names.
<< AT+SCAN=1,500,BT618
>> OK
+SCAN{
+SCAN=0,dc0d300002f9,-48,9,FSC-BT618
+SCAN}

Set a 5-second timeout and filter devices with the name “70CFC9A98840”.
<< AT+SCAN=1,500,BT618
>> OK
+SCAN{
+SCAN=0,70CFC9A98840,-52,9,Feasycom
+SCAN}

AT+TPMODE - Get/Set throughput mode

Command	AT+TPMODE{=Param}
`Param`	Mode（0~1，default 1） 0: Command Mode 1: Throughput Mode
Response	+TPMODE=Param
`Param`	Mode
Description	Command Mode： When bluetooth connected and in throughput mode, the AT command will be de-active. Throughput Mode： every byte received via physical UART will be sent to remote.

Example:
Throughput Mode
<< AT+TPMODE=1
>> OK

Command Mode
<< AT+TPMODE=0
>> OK

AT+ADVDATA - Get/Set advertising manufacturer specific data

Command	AT+ADVDATA{=Param}
`Param`	manufacturer specific data, tag 0xff(len <= 25>)
Response	+ADVDATA=Param
`Param`	manufacturer specific data, tag 0xff
Description	Get/Set advertising manufacturer specific data

Example:
Get advertising manufacturer specific data, \x is hexadecimal data
<< AT+ADVDATA
>> +ADVDATA=\x03\x01\x02
>> OK

Set advertising manufacturer specific data, \x is hexadecimal data
<< AT+ADVDATA=\x03\x01\x02
>> OK

AT+LESEND - Send data to remote device

Command	AT+LESEND{=Param1,Param2}
`Param1`	Connection index
`Param2`	data
Response	OK
Description	Send data to remote device

Example:
Send data to the connected device
<< AT+LESEND=4,2022
>> OK

AT+REBOOT - Soft Reboot

Command	AT+REBOOT
Response	OK
Description	Module release all Bluetooth connections then reboot

Example:
<< AT+REBOOT
>> OK

AT+RESTORE - Restore Factory Settings

Command	AT+RESTORE
Response	OK
Description	Module restore all factory settings then reboot

Example:
<< AT+RESTORE
>> OK

AT+PIOCFG - 开关引脚功能

Command	AT+PIOCFG{=param1,param2}
`param1`	Enable/Disable the function of the mode selection pin(default : 0) \| 0: Disable \| 1: Enable
`param2`	Enable/Disable the disconnect pin function(default : 0) \| 0: Disable \| 1: Enable
Response	OK
Description	Query and modify pin function

Example:
<< AT+PIOCFG=1,1
>> OK

Event Table

+SCAN - AT+SCAN=1 Scan Result

Indication	+SCAN=Param1,Param2,Param3,Param4,Param5,Param6
`Param1`	MAC address type (1 byte)
`Param2`	MAC address (12 Bytes ASCII)
`Param3`	RSSI
`Param4`	remote device name len
`Param5`	remote device name
Description	After the module receives AT+SCAN=1, it will continue to scan, and report through +SCAN after finding the device

Example:
SCAN device
<< AT+SCAN=1
>> +SCAN={
>> +SCAN=1,70CFC9A98840,-43,24,LE-Bose QuietControl 30
>> +SCAN=1,DC0D30001ED4,-65,10,FSC-BT946
>> +SCAN=}

+GATTSTAT - GATT State

Indication	+GATTSTAT=Param1,Param2
`Param1`	Connection Index
`Param2`	GATT State (1~3) 1: Standby 2: Connecting 3: Connected
Description	In the command mode, if the connection status of the module changes, it will be actively reported through +GATTSTAT

Example:
Connected
>> +GATTSTAT=0,3

+DATA - GATT Received Incoming Data

Indication	+DATA=Param1,Param2,Param3
`Param1`	Payload length
`Param2`	Payload
Description	In the throughput mode: report data without +DATA header In the command mode: report data with +DATA header +DATA=1,5,12345

Example:
received data 1234567890
>> +DATA=10,1234567890

Application scenarios

Get/Set the default parameters of the module

When the module is disconnect state, it will parse the uart data according to the AT command. The host can get and set the default parameters of the module, as shown in the figure below:

Set the device name to ABC
Get device name
Get MAC address

@startuml
hide footbox
skinparam sequenceMessageAlign center

box "local" #LightBlue
participant Host as host
participant Module as bt
end box

rnote over host, bt: Set the device name to ABC

host -> bt: AT+NAME=ABC\\r\\n
bt -> host: \\r\\nOK\\r\\n"

rnote over host, bt: Get device name

host -> bt: AT+NAME\\r\\n
bt -> host: \\r\\n+NAME=ABC\\r\\n\\r\\nOK\\r\\n"

rnote over host, bt: Get MAC address

host -> bt: AT+ADDR\\r\\n
bt -> host: \\r\\n+ADDR=DC0D30010203\\r\\n\\r\\nOK\\r\\n

@enduml

Process of sending data

When the module is powered on, it will continue to send advertising data, and the remote device (mobile phone) can scan the advertising packet. And initiate a connection request to the module. After the connection is successful, the module will pull up the connection status pin to notify the host that the Bluetooth connection is successful. The host can send data to the remote device through the Bluetooth module, and the remote device can also send data to the host.

@startuml
hide footbox
skinparam sequenceMessageAlign center

box "local" #LightBlue
participant Host as host
participant Module as bt
end box

box "remote" #LightBlue
participant ”Remote BT“ as remote
end box

rnote over host, remote: create connecion

bt --> remote: adv pkt
bt <- remote: scan
bt --> remote: adv pkt
bt <- remote: req create connection

rnote over host, remote: connecion successful

host <- bt: pull up the connection status pin

rnote over host, remote: send data

host -> bt: uart send ABC
bt -> remote: bt send ABC
bt <- remote: bt send DEF
host <- bt: uart send DEF

bt <- remote: disconnect connection

host <- bt: disconnect connection

host <- bt: pull down the connection status pin
bt --> remote: adv pkt

@enduml

The module acts as the central to connect to the remote device

The module can be used as a master device to connect to the slave device, and the host can send commands to control the module to scan and connect and disconnect. The figure below shows the process of connecting other devices:

Appendix

Download PDF Document

Download PDF Document