FSC-BT631D Programming User Guide

Introduction

Description

This design guide is suitable for engineers to develop FSC-BT631D Bluetooth modules

Module Default Settings

Name	FSC-BT631D-XXXX
LE-Name	FSC-BT631D-LE-XXXX
Pin Code	0000
Secure Simple Pairing Mode	On
UART Baudrate	115200/8/N/1

Hardware Description

Pin Diagram

Pin Description

Pin	Pin Name	Type	Pin Descriptions
14	I2S_OUT	O	I2S DATA OUT
15	I2S_CLK	I/O	I2S BCLK
16	I2S_IN	I	I2S DATA IN
17	I2S_WS	I/O	I2S SYNC
18	I2S_MCLK	I/O	I2S MCLK
21	LED0	I/O	LED0
22	LED1	I/O	LED1
23	RESET	I	External reset input: active Low
24	VBUS	VDD	3.3V power supply, recommended: use LDO power supply
25	GND	GND	GND
26	USB_DP	USB_DP	USB_DP
27	USB_DN	USB_DN	USB_DN
30	UART_RTS	I/O	UART RTS(default: PA mute pin)
31	UART_TX	O	UART TX
32	UART_RX	I	UART RX
33	UART_CTS	I/O	UART CTS(default: No connection required)
35	EXT_ANT	ANT	Change the 0 ohm resistance near the antenna, you can connect an external Bluetooth antenna

Hardware Design Notes

The simple test of the module only needs to connect VDD/VDD_IO/VREG_IN/GND/UART_RX/UART_TX to use
After drawing the schematic diagram, please send it to Feasycom for review,so as to avoid the Bluetooth distance not reaching the best effect

Function Description

BT631D is a module that supports both classic Bluetooth and LE Audio. Currently, LE Audio supports BIS function, and more other functions will be developed in the future.
As the transmitter of BIS, the audio source can be the A2DP of the mobile phone, I2S input (for the development board, it is an analog input, currently only supports the external codec TLV320AIC3204), or USB.

Profiles & Features

SPP (Serial Port Profile)
GATTS (Generic Attribute Profile LE-Peripheral role)
GATTC (Generic Attribute Profile LE-Central role)
HFP-HF (Hands-Free Profile)
HFP-AG (Hands-Free-AG Profile)
A2DP-Sink (Advanced Audio Distribution Profile)
A2DP-Source (Advanced Audio Distribution Profile)
AVRCP-Controller (Audio/Video remote controller Profile)
AVRCP-Target (Audio/Video remote controller Profile)
HID-DEVICE (Human Interface Profile)
PBAP (Phonebook Access Profile)
BIS (broadcast isochronous stream)
CIS (Connected Isochronous Stream)

GATT Default service and characteristic

Type	UUID	Characteristic	Description
Service	0xFFF0		throughput services
Write	0xFFF2	Write，Write Without Response	app send to module
Notify	0xFFF1	Notify	module send to app

Command Description

Terms

Throughout this specification:

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

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>
Module will always report command’s execution result by using “OK” for success or “ERROR” for failure

Error Code	Meaning
001	Failed
002	Invalid parameter
003	Invalid state
004	Command mismatch
005	Busy
006	Command not supported
007	Profile not turned on
008	No memory
Others	Reserved for future use

Example:
Read module’s BR/EDR local name
<< AT+VER
>> +VER=FSC-BT631D-XXXX
>> OK

Pick up an incoming call when no call incoming actually
<< AT+HFPANSW
>> ERR003

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 ‘,’
Use the command AT+SEP to replace the default separator to prevent conflicts

Example:
Received “1234567890” from mobile phone via SPP profile
>> +SPPDATA=10,1234567890

Call phone 10086
>> +HFPSTAT=4
>> +HFPAUDIO=1
>> +HFPSTAT=6,10086

Commands Table

General Commands

AT+HELP - Firmware Function/Command Summary

Command	AT+HELP
Response	<FIRMWARE FUNCTION: appropriate working scenario > <OTA PATH: latest suitable firmware path on server for upgrade On-The-Air> <ENABLED PROFILES: LINKS: ON/OFF> … … <COMMAND SUMMARY: DESCRIPTION: PROFILE CATEGORY>
Description	Using help command to get the basic summary information

Note

If you need to upgrade to the latest version, please refer to FSC-BT631D OTA User Guide

AT+SEP - Read/write Event delimiter

Command	AT+SEP{=Param}
`Param`	Setting range 0x01~0xFF, default: ‘,’, where ‘0’ means 0xFF
Response	Returns the current delimiter
Description	Parameters for events/responses, which may contain the same value as the default delimiter, Use this command to replace the default delimiter to prevent conflicts. (Usually the default delimiter “,” is replaced by the hexadecimal value “xFF”)

Example:Read the pairing record of the module
<< AT+PLIST
>> +PLIST=1,32808,1C5CF226D773, Tony, iPhone12
>> +PLIST=2,40, A0BC30075421, Samsung S8
>> +PLIST=E
>> OK
Example: Set the separator to ‘0xFF’
<< AT+SEP=0
>> OK
Example: Read the pairing record of the module again
<< AT+PLIST
>> +PLIST=1<FF>32808<FF>1C5CF226D773<FF>Tony, iPhone12
>> +PLIST=2<FF>40<FF> A0BC30075421<FF>Samsung S8
>> +PLIST=E
>> OK

AT+VER - Get Firmware Version

Command	AT+VER
Response	+VER=Param1,Param2,Param3
`Param1`	Module type
`Param2`	Firmware version
`Param3`	Production Date
Note	After upgrading the firmware, the production date will not change

Example:
<< AT+VER
>> +VER=BT631D,V2.6.1,20220922
>> OK

AT+BAUD - Get/Set Uart Baudrate

Command	AT+BAUD{=Param}
`Param`	2400/4800/9600/19200/38400/57600/115200(default)/128000/ 230400/256000/460800/512000/921600/1382400
Response	+BAUD=Param1,Param2,Param3
`Param`	Returns all currently supported baud rates
Description	The module will switch the baud rate immediately after receiving this command. BT631D and BT955 do not support 2400

Example:
Read module’s baudrate
<< AT+BAUD
>> +BAUD=2400,4800,9600,19200,38400,57600,115200,128000,230400,256000,
460800,512000,921600,1382400
>> OK

Set baud rate
<< AT+BAUD=9600
>> OK

AT+I2CREG - Read/write I2C registers

Command	AT+I2CREG=Param1, Param2, Param3 {,Param4}
`Param1`	i2c bus address, 2 byes hex string
`Param2`	i2c register address, 2/4 byes hex string
`Param3`	bytes to read/write (1~64)
`Param4`	value to write
Response	+I2CREG=Param
`Param`	Returns the current value read by I2C
Note	The current version of BT631D does not fully support this command, please do not use it. Reserved for subsequent releases.

Example:Read external I2C slave device, address:0x34, register 0003, bytes:2; and modify 0xA13B
<< AT+I2CREG= 34,0003,2
>> +I2CREG=805F
>> OK
<< AT+I2CREG= 34,0003,2,A13B
>> OK

AT+I2SCFG - Get/Set I2S Settings

Command	AT+I2SCFG{=Param}
`Param`	A base-10 representation of a bit field, for each bit
`BIT[0]`	0:disable; 1:enable
`BIT[1]`	0:master; 1:slave
`BIT[2]`	0:FS=48000Hz;1:FS=44100Hz
`BIT[3-4]`	00: I2S standard format 10: PCM short frame format
`BIT[5-6]`	00: bit depth=16bits 10: bit depth=32bits (only 16bits of MSB effective) 11: bit depth=32bits (only used for PCM mode)
Response	+I2SCFG=Param
Note	The current version of BT631D does not fully support this command, please do not use it. Reserved for subsequent releases.

Example:Usual configuration and description:

0	In simulation mode, the module will detect the internal/external codec through I2C at startup and report +CODEC=id
1	I2S Master; Sample rate=48000Hz; Resolution=16bits; Bit clock= 48000162ch=1.536Mhz
3	I2S Slave; Sample rate=48000Hz; Resolution=16bits; Bit clock= 48000162ch=1.536Mhz
65	I2S Master; Sample rate=48000Hz; Resolution=32bits; Bit clock= 48000322ch=3.072Mhz
67	I2S Slave; Sample rate=48000Hz; Resolution=32bits; Bit clock= 48000322ch=3.072Mhz
113	PCM Master; Sample rate=48000Hz; Resolution=16bits; Bit clock= 48000162ch=1.536Mhz

AT+MICGAIN - Get/Set Analog Input Gain

Command	AT+MICGAIN{=Param1,Param2}
`Param1`	music gain (0~15, default:8)
`Param2`	call gain (0~15, default:8)
Description	Adjust Codec analog input volume

AT+SPKVOL - Get/Set Analog Output Volume

Command	AT+SPKVOL{=Param1,Param2}
`Param1`	A2DP Volume (0~15, default:10)
`Param2`	HFP Volume (0~15, default:10)
Description	Adjust Codec analog output volume

AT+REBOOT - Soft Reboot

Command	AT+REBOOT
Response	OK
Description	Module release all Bluetooth connections with remote device 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+BTEN - Bluetooth On/Off

Command	AT+BTEN{=Param}
`Param`	0-Power off 1-Power on

AT+PROFILE - Bluetooth Profile Selection

Command	AT+PROFILE{=Param}
`Param`	A base-10 representation of a bit field, for each bit:
`BIT[0]`	SPP (Serial Port Profile)
`BIT[1]`	GATT Server (Generic Attribute Profile)
`BIT[2]`	GATT Client (Generic Attribute Profile)
`BIT[3]`	HFP-HF (Hands-Free Profile Handsfree)
`BIT[4]`	HFP-AG (Hands-Free Profile Audio Gateway)
`BIT[5]`	A2DP Sink (Advanced Audio Distribution Profile)
`BIT[6]`	A2DP Source (Advanced Audio Distribution Profile)
`BIT[7]`	AVRCP Controller (Audio/Video remote controller Profile)
`BIT[8]`	AVRCP Target (Audio/Video remote controller Profile)
`BIT[9]`	HID Keyboard (Human Interface Profile)
`BIT[10]`	PBAP Server (Phonebook Access Profile)
`BIT[13]`	BIS/CIS Gateway (LE AUDIO gateway)
`BIT[14]`	BIS/CIS Headset (LE AUDIO headset)
`BIT[15]`	*** (For iOS devices)
Response	+PROFILE=Param
Description	GATT Server and Client, HFP Sink and Source cannot be enabled at the same time, A2DP Sink and Source,AVRCP Controller and Target. BIS Headset can only be enabled individually. The default Profile: 9387 can be connected by the mobile phone through A2DP, and the audio will be broadcast through BIS.

Example:Read current profile selection
<< AT+PROFILE
>> +PROFILE=1195
Example:Only enable A2DP Sink, HFP Sink,disable the others
<< AT+PROFILE=160
>> OK
Example:Only enableA2DP Source,HFP Source,disable the others
<< AT+PROFILE=80
>> OK

AT+AUTOCONN - Turn On/Off Power On Auto Reconnect

Command	AT+AUTOCONN{=Param}
`Param`	Expressed in decimal bit field, format reference: AT+PROFILE
Response	+AUTOCONN=Param
Description	Module will attempt to connect last device after power on if set.

AT+STAT - Get All Profile State

Command	AT+STAT
Response	+STAT=Param1, Param2, Param3…
Description	Query the current status of all enabled Profiles

Example:Read the current Profile
<< AT+PROFILE
>> +PROFILE=83
Example:Read Profile status
<< AT+STAT
+STAT=3,1,2,5
>> OK

AT+DEVSTAT - Read Device State

Command	AT+DEVSTAT
Response	+DEVSTAT=Param
`Param`	Represented in decimal bit field,
`BIT[0]`	0: Power Off; 1: Power On
`BIT[1]`	0: BR/EDR Not Discoverable; 1: BR/EDR Discoverable
`BIT[2]`	0: BLE Not Advertising; 1: BLE Advertising
`BIT[3]`	0: BR/EDR Not Scanning; 1: BR/EDR Scanning
`BIT[4]`	0: BLE Not Scanning; 1: BLE Scanning

Example:Usual configuration and description:

0	Device power off
1	Device power on
3	Device power on, BR/EDR Discoverable
5	Device power on, BR/EDR Not Discoverable, BLE Advertising
7	Device power on, BR/EDR Discoverable, BLE Advertising
13	Device power on, BR/EDR Not Discoverable, BLE Advertising, Scanning nearby BR/EDR devices

AT+ADDR - Read BR/EDR Bluetooth MAC address

Command	AT+ADDR
Response	+ADDR=Param
`Param`	Module’s BR/EDR Bluetooth MAC address (12 Bytes ASCII)

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

AT+LEADDR - Get BLE MAC Address

Command	AT+LEADDR
Response	+LEADDR=Param
`Param`	Module’s BLE Bluetooth MAC address (12 Bytes ASCII)

AT+NAME - Get/Set BR/EDR Local Name

Command	AT+NAME{=Param1{,Param2}}
`Param1`	BR/EDR local name(1~31 Bytes ASCII)
`Param2`	MAC address suffix(0/1,default:1) 0: Disable suffix 1: Enable suffix “-XXXX” (lower 4 bytes of MAC address) after local name
Response	+NAME=Param
`Param`	+NAME=Param
Description	Write local name if parameter exist, otherwise read current local name

Example:
Read current BR/EDR local name
<< AT+NAME
>> +NAME=FSC-BT631D-XXXX
>> OK

Change module’s BR/EDR local name to “ABC”,and disable suffix
<< AT+NAME=ABC,0
>> OK

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

AT+LENAME - Get/Set BLE Local Name

Command	AT+LENAME{=Param1{,Param2}}
`Param1`	BLE local name(1~25 Bytes ASCII)
`Param2`	MAC address suffix(0/1,default:1) 0: Disable suffix 1: Enable suffix “-XXXX” (lower 4 bytes of MAC address) after local name
Response	+LENAME=Param
Description	In BIS Headset mode, the module will actively search for and local Bluetooth BIS Gateway device with the same name and actively establish synchronization.

AT+SSP - Read/write BR/EDR pairing mode

Command	AT+SSP{=Param}
`Param`	Pairing mode (0~3, default:2) (0) Legacy pairing, use pin code for pairing (1) Secure simple pairing, auto pairing (2) Secure simple pairing, display yes/no in pairing (3) Secure simple pairing, passkey compare, user need to accept/reject pair request with command AT+CFM
Response	+SSP=Param
Note	Take effect after restart

AT+PIN - Get/Set BR/EDR Pin Code

Command	AT+PIN{=Param}
`Param`	Pin code(4~15 Bytes ASCII, default:0000)
Response	+PIN=Param
Description	Pin code only work in legacy pairing mode, see AT+SSP

Example:
Read module’s pin code
<< AT+PIN
>> +PIN=0000
>> OK

Change module’s pin code to 1234
<< AT+PIN=1234
>> OK

AT+CFM - Accept/reject pairing requests from the remote end

Command	AT+CFM=Param1, Param2
`Param1`	MAC address of the remote device(12Bytes)
`Param2`	0-Reject the remote pairing request 1-Accept pairing requests from the remote end
Description	When +SSP=3, the CFM command is valid

AT+COD: Get/Set Device Class

Command	AT+COD=Param
`Param`	Class of device(6 bytes ASCII, default:240408 Handsfree device)
Response	+COD=Param

Related configuration reference: COD.

AT+PAIR: Get/Set BR/EDR/BLE Visibility

Command	AT+PAIR=Param
`Param`	Mode(0-3) 0: Leave BR/EDR/BLE discoverable mode (stop advertising/broadcasting) 1: Enter BR/EDR discoverable mode (start broadcasting) 2: Enter BLE discoverable mode (start advertising) 3: Enter BR/EDR/BLE discoverable mode (start advertising/broadcasting)
Description	Module will always be discoverable if no device connected (BR/EDR or BLE), and be undiscoverable if connected with remote device, unless received this command

AT+PAGE: Read/write BR/EDR connectable mode

Command	AT+PAGE=Param
`Param`	Mode(0-1) 0: Leave BR/EDR connectable mode (stop paging) 1: Enter BR/EDR connectable mode (start paging)
Description	If no device is connected, the module will always be in connectable mode, If connected to a remote device, the module will not be connectable unless this command is received

AT+SCAN - Scan Nearby Devices

Command	AT+SCAN=Param1{,Param2{,Param3}}
`Param1`	scan type（0~2） 0: Stop scan 1: Scan nearby BR/EDR devices 2: Scan nearby BLE devices(Some programs do not support) 3: Scan nearby BR/EDR/BLE devices(Some programs do not support)
`Param2`	(1~48)Scan time，unit:1.28s, default:12.8s
`Param3`	(1~25 Bytes ASCII)filter name.
Description	Format description reference: +SCAN - Scan Result

AT+RSSI: Read BR/EDR signal strength

Command	AT+RSSI=Param
`Param`	MAC address of the currently connected device
Response	+PIN=Param
`Param`	RSSI value (-127 ~ 0)

AT+PLIST - Get/Delete Paired List

Command	AT+PLIST{=Param}
`Param`	(0/1~8/12 Bytes MAC address) (0) Clear all paired record (1~8) Clear specific paired record with index (MAC) Clear specific paired record with MAC address
Response1	+PLIST=Param1, Param2, Param3{,Param4}
`Param1`	(1~8) Paired device’s index
`Param2`	In decimal digit field, device connection profile, refer to AT+PROFILE
`Param3`	(MAC)Paired device’s MAC address
`Param4`	(UTF8)Paired device’s name
Response2	+PLIST=E End of the paired record

Example:Read module’s paired record
<< AT+PLIST
>> +PLIST=1,32808,1C5CF226D773, iPhone12
+PLIST=2,40, A0BC30075421, Samsung S8
+PLIST=E
>> OK

Example:Clear module’s paired record
<< AT+PLIST=0
>> OK

AT+DSCA - Release All Connections

Command	AT+DSCA
Description	Module release all Bluetooth connections with remote device

AT+AUDROUTE - Audio Route Manager

Command	AT+AUDROUTE{=Param}
`Param`	Note: HF1 & HF2 means peer Bluetooth headphones 0 Stop audio routing 1 Route music (a2dp streaming) from Module to HP1/HP2 simultaneously 2 Route voice call (hfp sco) between Module and HP1 3 Route voice call (hfp sco) between Module and HP2 4 Route voice call (hfp sco) between HP1 and HP2 (intercom mode) 5 Route voice call (hfp sco) from Module to HP1/HP2 simultaneously 6 Route music (a2dp streaming) from Module to HP1 only 7 Route music (a2dp streaming) from Module to HP2 only
Description	Some route mode require specify firmware version, refer to application note for more description: Source mode connection

AT+AUXCFG - Audio Input Mode Configuration

Command	AT+AUXCFG{=Param}
`Param`	Mode (0~3, Default:2) 0: Audio input via USB 1: Audio input via I2S 2: Audio input via A2DP 3: Audio is input via A2DP but is no longer broadcast out via BIS
Response	+AUXCFG=Param

AT+TPMODE - Turn On/Off Throughput Mode

Command	AT+TPMODE{=Param}
`Param`	Throughput mode(0~1，default:0） 0: Turn Off 1: Turn On
Response	+TPMODE=Param
Description	When SPP/GATT profile connected and throughput mode is on, the AT command will be de-active, every byte received via physical UART will be sent to air, vice visa

AT+LINKCFG - Automatic search link configuration

Command	AT+LINKCFG{=Param}
`Param`	Refer to AT+PROFILE command
Description	If this command module is configured, it will automatically search for links based on the configured profile.

Example:Configure A2DP automatic search links
<< AT+PROFILE=64
>> OK

AT+TXPOWER - tx power configuration

Command	AT+TXPOWER{=Param}
`Param`	(value:0-7, Default：7)
Description	Only valid for BT631D Classic Bluetooth part

Value	Power(dBm)
0	-24
1	-20
2	-16
3	-12
4	-8
5	-4
6	0
7	4

HFP Command

AT+HFPSTAT - Read HFP State

Command	AT+HFPSTAT
Response	+HFPSTAT=Param1{,Param2{,Param3}}
Description	Format description reference: +HFPSTAT - HFP State

AT+HFPSR - Read/Write HFP Sample rate

Command	AT+HFPSR{=Param}
`Param`	Sampling rate during HFP call, configurable: 0/8000/16000/48000 Default:0
Response	+HFPSR=Param
Description	This parameter will override the voice call settings in AT+I2SCFG, and use this parameter to set the sampling rate of HFP I2S

AT+HFPCFG - Read/Write HFP configuration

Command	AT+HFPCFG{=Param}
`Param`	Expressed in decimal bit field, default: 2
`BIT[0]`	0-When HFP is disconnected abnormally, the link to the last disconnected device will not be restored. 1-When HFP is disconnected abnormally, the link to the last disconnected device will not be restored.
`BIT[1]`	0-Turn off the echo cancellation function; 1-turn on the echo cancellation function
`BIT[2]`	0-turn off the three-way calling function, 1-turn on the three-way calling function (the firmware needs to support the three-party calling function)

AT+HFPCONN - Establish HFP Connection

Command	AT+HFPCONN{=Param}
`Param`	MAC address of target device(12 Bytes ASCII)
Description	Reconnect to last HFP device if parameter not exist

Example:Connect to last HFP device
<< AT+HFPCONN
>> OK
Example:Connect to specific HFP device with MAC address
<< AT+HFPCONN=1C5CF226D773
>> OK

AT+HFPDISC - Release HFP Connection

Command	AT+HFPDISC
Description	Release current HFP connection with remote device

AT+HFPDIAL - Redial/Dial phone number

Command	AT+HFPDIAL{=Param}
`Param`	Phone number (1~25 Bytes ASCII)
Description	Dial specific number if parameter exist, otherwise redial

Example:Redial
<< AT+HFPDIAL
>> OK
Example:Dial “075527924639”
<< AT+HFPDIAL=075527924639
>> OK

AT+HFPDTMF - Send DTMF

Command	AT+HFPDTMF{=Param}
`Param`	*DTMF (0~9/#/)**

Example:During call，send DTMF “＃”
<< AT+HFPDTMF=#
>> OK

AT+HFPANSW - Pick up Incoming Call

Command	AT+HFPANSW
Description	Pick up an incoming call

AT+HFPCHUP - Reject/hang up incoming and outgoing calls

Command	AT+HFPCHUP
Description	Reject an incoming call or hang up an outgoing call/conversation

AT+HFPMCAL - Three-way call control

Command	AT+HFPMCAL=Param
`Param`	0: Release held call or reject waiting call 1: Release active call and accept another call 2: Hold active call and accept another call
Description	See application scenarios: HFP three-way call operation

AT+HFPADTS - Voice Switching

Command	AT+HFPADTS=Param
`Param`	1: Stream voice audio from module to remote device 2: Transfer voice audio from remote device to module
Description	If the parameter is empty, alternate switching

AT+HFPVR - Start/Stop speech recognition on remote device

Command	AT+HFPVR=Param
`Param`	0-Stop 1-Start
Description	Start/stop speech recognition for remote devices (e.g. Siri for iOS devices)

AT+HFPINFO - Read HFP current information

Command	AT+HFPINFO
Description	Returns the current HFP status, signal strength, battery, device name and other information

AT+MICMUTE - Mute Microphone

Command	AT+MICMUTE=Param
`Param`	0-unmute 1-mute
Description	Mute local microphone during calls

A2DP/AVRCP Commands

AT+A2DPSTAT - Read A2DP State

Command	AT+A2DPSTAT
Response	+A2DPSTAT=Param
Description	Format description reference: +A2DPSTAT - A2DP State

AT+A2DPCONN - Establish A2DP Connection

Command	AT+A2DPCONN{=Param}
`Param`	MAC address of target device(12 Bytes ASCII)
Description	Reconnect to last A2DP device if parameter not exist

AT+A2DPDISC - Release A2DP Connection

Command	AT+A2DPDISC
Description	Release current A2DP connection with remote device

AT+A2DPINFO - Read A2DP Current Information

Command	AT+A2DPINFO
Description	Returns the current A2DP status, remote device name and other information

AT+A2DPSR - Write A2DP Sample rate

Command	AT+A2DPSR=Param
`Param`	Sample rate:48000/44100
Description	The setting is valid in A2DP Source mode

AT+AVRCPSTAT - Read AVRCP State

Command	AT+AVRCPSTAT
Response	+AVRCPSTAT=Param
Description	Format description reference: +AVRCPSTAT - AVRCP State

AT+AVRCPCFG - Read/Write AVRCP Configuration

Command	AT+AVRCPCFG{=Param}
`Param`	A base-10 representation of a bit field, default:3, for each bit:
`BIT[0]`	Auto get track ID3 information (title, artist, album) on track changed.default:1
`BIT[1-3]`	Auto get track play progress if value > 0. 默认:1(second)
`BIT[4]`	Player browsing function enable/disable
`BIT[5]`	Specify a folder to automatically pull media cover images

Example: Read AVRCP Configuration
<< AT+AVRCPCFG
>> +AVRCPCFG=1
OK
Example: Set to 5 seconds to report playback progress
<< AT+AVRCPCFG=9
>> OK

AT+PLAYPAUSE - Track Play/Pause

Command	AT+PLAYPAUSE
Description	Send play or pause command to remote media player according to current play status

AT+PLAY - Track Play

Command	AT+PLAY
Description	Send play command to remote media player

AT+PAUSE - Track Pause

Command	AT+PAUSE
Description	Send pause command to remote media player

AT+STOP - Track Stop

Command	AT+STOP
Description	Send stop command to remote media player

AT+FORWARD - Track Forward

Command	AT+FORWARD
Description	Send forward command to remote media player

AT+BACKWARD - Track Backward

Command	AT+BACKWARD
Description	Send backward command to remote media player

AT+REPEAT - Set media player repeat mode

Command	AT+REPEAT{=Param}
`Param`	Repeat mode (0/1) 0-Turn Off 1-Turn On
Response	+PLAYMODE=Param1,Param2
`Param`	Format description reference: +PLAYMODE - Media Player Repeat/Shuffle Mode

AT+SHUFFLE - Set media player shuffle mode

Command	AT+SHUFFLE{=Param}
`Param`	Shuffle mode (0/1) 0-Turn Off 1-Turn On
Response	+PLAYMODE=Param1,Param2
`Param`	Format description reference: +PLAYMODE - Media Player Repeat/Shuffle Mode

AT+GETMP - Get the media player of the remote device

Command	AT+GETMP
Response	+BROWDATA=Param1,Param2,Param3,Param4
`Param`	Format description reference: +BROWDATA - Media Player File System Browsing Data
Description	Get the media player of the remote device. Only players with the browsable flag set support browsing. For some mobile phones (such as iOS devices), users may need to start the player on the mobile phone for the first time Please see application scenarios: AVRCP file system browsing

AT+SETMP - Select media player

Command	AT+SETMP=Param
`Param`	Media player index
Response	+BROWDATA=Param1,Param2
`Param`	Format description reference: +BROWDATA - Media Player File System Browsing Data
Description	To select a media player to browse, the player’s browsable flag must be set. After selecting the player we will enter the root directory, please refer to the application scenario: AVRCP file system browsing

AT+GETFD - List Subfolders/Tracks of Selected Folder

Command	AT+GETFD=Param1,Param2
`Param1`	Starting position, (1~65535)
`Param2`	End position, (1~65535), Param2 >= Param1
Description	List subfolders or media items in the current folder. Please see application scenarios: AVRCP file system browsing

AT+SETFD - Select And Enter The Folder

Command	AT+SETFD=Param
`Param`	0:Enter up level folder other:Enter selected folder
Description	Select and enter the folder to browse. Please see application scenarios: AVRCP file system browsing

AT+GETNP - List tracks in the “Now Playing” list

Command	AT+GETNP=Param1,Param2
`Param1`	(1~65535),Start position
`Param2`	(1~65535),End position, Param2 >= Param1
Response	+BROWDATA=M,Param1,Param2,Param3
`Param`	Format description reference: +BROWDATA - Media Player File System Browsing Data

AT+ADDMP - Add tracks to media player

Command	AT+ADDMP=Param
`Param`	Track ID
Description	Add selected tracks to media player and start playing

PBAP指令

AT+PBSTAT - Read PBAP state

Command	AT+PBSTAT
Response	+PBATAT=Param
Description	Format description reference: +PBSTAT - PBAP State

AT+PBCONN - Establish PBAP Connection

Command	AT+PBCONN{=Param}
`Param`	MAC address of target device(12 Bytes ASCII)
Description	Module will use current HFP device’ MAC address if parameter not exist For some firmware release, module will establish PBAP connection automatically on received command AT+PBDOWN

AT+PBDISC - Release PBAP Connection

Command	AT+PBDISC
Description	Release current PBAP connection with remote device

AT+PBDOWN - Download Phonebook

Command	AT+PBDOWN=Param1{,Param2}
`Param1`	Phonebook type(0-5) (0) Phonebook (SIM Storage) (1) Phonebook (Phone Storage) (2) Received call log (3) Dialed call log (4) Missed call log (5) All call log
`Param2`	Max items (1~65535, default:3000 for phonebook; 50 for call log)
Description	For some phones (e.g. iPhone), the contact download permission must be turned on in phone’s Bluetooth settting refer to application note for more description: Phonebook/Contact photo download

AT+PBABORT - Cancel Phonebook Download

Command	AT+PBABORT
Description	Cancel phonebook download

BIS Command

AT+BISCONN - Connecting to the BIS Gateway device

Command	AT+BISCONN{=Param}
`Param`	Target device Bluetooth name. If no parameters are provided, it will automatically search and connect to the BIS Gateway device.

CIS Command

AT+CISCONN - Connecting to the CIS Headset device

Command	AT+CISCONN{=Param}
`Param`	Target device Bluetooth name. Automatically connects to the right earpiece after connecting to the left earpiece. If no parameters are provided, it will reconnect to the previously connected device.

AT+AUDIOMODE - Turn On/Off CIS Mode

Command	AT+AUDIOMODE=Param
`Param1`	(0) Turn off CIS mode,Turn on BIS mode (1) Turn on CIS mode,Turn off BIS mode

AT+AUDIOCH - Select audio channel

Command	AT+AUDIOCH=Param
`Param1`	(0) Left audio channel (1) Right audio channel

AT+TALK - Turn On/Off CIS Intercom Communication

Command	AT+TALK=Param
`Param1`	(0) Turn off Intercom (1) Turn on Intercom
Description	The intercom feature requires establishing a CIS connection first, and the audio source of CIS cannot be A2DP. The intercom function is established between the transmitter and receiver (left audio channel) of CIS.

SPP Command

AT+SPPSTAT - Read SPP State

Command	AT+SPPSTAT
Response	+SPPATAT=Param
Description	Format description reference: +SPPSTAT - SPP State

AT+SPPCONN - Establish SPP Connection

Command	AT+SPPCONN{=Param}
`Param`	MAC address of target device(12 Bytes ASCII)

AT+SPPDISC - Release SPP Connection

Command	AT+SPPDISC
Description	Release current SPP connection with remote device

AT+SPPSEND - Send Data Via SPP

Command	AT+SPPSEND=Param1,Param2
`Param1`	Payload length (1~492)
`Param2`	Payload (1~492 Bytes UTF8)
Description	If throughput mode is on, this command is de-active

Example: Send data “1234567890” to remote device via SPP
<< AT+SPPSEND=10,1234567890
>> OK

GATT Server Command

AT+GATTSTAT - Read GATT State

Command	AT+GATTSTAT
Response	+GATTATAT=Param
Description	Format description reference: +GATTSTAT - GATT State

AT+GATTDISC - Release GATT Connection

Command	AT+GATTDISC
Description	Release current GATT connection with remote device

AT+GATTSEND - Send Data Via GATT

Command	AT+GATTSEND=Param1,Param2
`Param1`	Payload length (1~492)
`Param2`	Payload (1~492 Bytes UTF8)
Description	If throughput mode is on, this command is de-active

Example: Send data “1234567890” to remote device via GATT
<< AT+SPPSEND=10,1234567890
>> OK

GATT Client Command

AT+LECONN - GATT Server Connection

Format	+LECONN=Param1,Param2 {, Param3{, Param4}}
`Param1`	12-byte device address + 1-byte address type（0:public,1:random）
`Param2`	ServiceUUID (16 or 128 bit)
`Param3`	WriteUUID (16 or 128 bit)
`Param4`	NotifyUUID (16 or 128 bit)
Description	Initiates 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. The address type is obtained by using the AT+SCAN=2 command to scan the third parameter returned :ref: ‘REF100’ Example :+SCAN=0,-74,2,DD0D30037591 indicates that the LE device broadcasts data

Example: Connect the GATT Server with DD0D30037591. The ServiceUUID is 0xFFF0, WriteUUID is 0xFFF2, and NotifyUUID is 0xFFF1
<< AT+LECONN=DD0D300375911,FFF0,FFF2,FFF1
<< OK

AT+LEDISC - Release GATT Connection

Command	AT+LEDISC
Description	Disconnect the current GATT connection from the remote device

AT+LESEND - Send Data Via GATT

Format	+LESEND=Param1,Param2
`Param1`	Payload length
`Param2`	Payload
Description	If throughput mode is on, this command is de-active

Example: Send data to remote device through GATT Client “1234567890”
<< AT+LESEND=10,1234567890
>> OK

HID Command

AT+HIDSTAT - Read HID State

Command	AT+HIDSTAT
Response	+HIDATAT=Param
Description	Format description reference: +HIDSTAT - HID State

AT+HIDCONN - Establish HID Connection

Command	AT+HIDCONN{=Param}
`Param`	MAC address of target device(12 Bytes ASCII)

AT+HIDDISC - Release HID Connection

Command	AT+HIDDISC
Description	Release current HID connection with remote device

AT+HIDMODE - Get/Set HID Input Mode

Command	AT+HIDMODE{=Param}
`Param`	HID keyboard input mode(0~1), default 1 (0) Hex key code (1) Ascii key code (English)
Note	Module can support various keyboard language with specify firmware, such as: TURKEY SPAIN PORTUGAL FRANCE GERMANY ITALY CZECH JAPAN

AT+HIDDLY - Get/Set HID Report Period

Command	AT+HIDDLY{=Param}
`Param`	HID report period in millisecond, default 10 ms

AT+HIDSEND - Send HID Keyboard Report

Command	AT+HIDSEND=Param1,Param2
`Param1`	Report length
`Param2`	Report payload
Note	For special key code: 0x0D -> ENTER 0x08 -> BACKSPACE 0x09 -> TAB 0x20 -> SPACE
Description	If throughput mode is on, this command is de-active

Example: Send key code ‘A’ to remote device  (on AT+HIDMODE=1)
>> AT+HIDSEND=1,A
<< OK
Example: Send key code ‘4’ to remote device (on AT+HIDMODE=0)
<< AT+HIDSEND=4, xA1 x01 x00 x04
>> OK
Note: As payload is hex value, hence actual command is:
41 54 2B 48 49 44 53 45 4E 44 3D 34 2C A1 01 00 04 0d 0a
Where:
A1 : report start
01 : page id 1
00 : modifier
04 : key code
Module will auto send debounce key code by itself

AT+HIDCMD - Send HID User Report

Command	AT+HIDCMD=Param
`Param`	2 bytes hid user report e.g., for iPhone: Play/Pause: 00 CD Stop: 00 B7 Forward: 00 B5 Backward: 00 B6 Fast Forward: 00 B3 Rewind:00 B4 Record:00 B2 VolumpUp:00 E9 VolumpDn:00 EA Mute:00 E2 On screen keyboard Toggle:01 AE
Description	If throughput mode is on, this command is de-active

Example: Send Volume Up to iPhone
<< AT+HIDCMD= x00 xE9
>> OK
Note: As the payload is hex value, hence actual command is:
41 54 2B 48 49 44 43 4D 44 3D 00 E9 0D 0A

Events Table

General Events

+PWRSTAT - Power on status

Format	+PWRSTAT=Param
`Param`	0-Powering off 1-Powering on(booting)
Description	It is not recommended to use AT commands during power on and off.

+SCAN - Scan Result

Format1	+SCAN =Param1,Param2,Param3, Param4,Param5,Param6
`Param1`	Index
`Param2`	RSSI (-127 ~ -1)
`Param3`	Device address type (0~3) (0) BR/EDR address (1) LE public address (2) LE random address (3) iOS device with Carplay support
`Param4`	MAC address (12 Bytes ASCII)
`Param5`	BR/EDR device name or LE device broadcast data
`Param6`	Device type(6 Bytes ASCII)
Format2	+SCAN=E: Stop scan

Example: Scan BR/EDR nearby devices

<< AT+SCAN=1

>> OK

+SCAN=1,-32,3,B019C66209FA,wt-iphone,7A020C
+SCAN=2,-74,0,DC0D30000053,BW226,040680
+SCAN=3,-43,0,00158354F994,LAPTOP-3L,120104
+SCAN=E

+PAIRREQ - Pairing Request

Format	+PAIRREQ=Param1,Param2{,Param3}
`Param1`	Passkey (000000~999999)
`Param2`	The MAC address of the currently paired device (12 Bytes ASCII)
`Param3`	The name of the currently paired device

+PAIRED - Pair Result

Format	+PAIRED=Param1,Param2
`Param1`	Pair Result (0)-Success (1~255)-Failure reason
`Param2`	The MAC address of the currently paired device (12 Bytes ASCII)

+CODEC - Codec ID

Format	+CODEC=Param
`Param`	Code id
Description	This command is currently invalid, please ignore it

HFP Events

+HFPSTAT - HFP State

Format	+HFPSTAT=Param1{,Param2{,Param3}}
`Param1`	(0~10) (0) Unsupported (1) Standby (2) Connecting (3) Connected (4) Outgoing call (5) Incoming call (6) Active call (7) Active held (3-way-calling) (8) First call active, second call waiting (3-way-calling) (9) First call active, second call held (3-way-calling) (10) First call outgoing, second call held (3-way-calling)
`Param2`	Phone number, When status>3
`Param3`	Phone number (three-way call)

Example: Call 10086
<< AT+HFPDIAL=10086
>> +HFPSTAT=3
>> +HFPSTAT=4,10086
>> +HFPAUDIO=1
Example: The call is coming and the number is 13265463800
>> +HFPSTAT=5, 13265463800
>> +HFPAUDIO=1

+HFPDEV - HFP Remote Device Information

Format	+HFPDEV=Param1{,Param2}
`Param1`	(12 Bytes ASCII), 当前HFP连接远端设备的MAC地址
`Param2`	(UTF8), 当前HFP连接远端设备的名称

Example: HFP connect success with device

>> +HFPDEV=1C5CF226D774, iPhone

+HFPAUDIO - HFP Voice Audio State

Format	+HFPAUDIO=Param
`Param`	(0) HFP voice audio disconnected, audio input/output routed to remote device (1) HFP voice audio connected, audio input/output routed to module

+HFPSIG - HFP Remote Device Network Signal Strength

Format	+HFPSIG=Param
`Param`	(0~5) Network signal strength of remote device

+HFPROAM - HFP Remote Device Roaming State

Format	+HFPROAM=Param
`Param`	(0/1) Roaming state of remote device

+HFPBATT - HFP Remote Device Battery Level

Format	+HFPBATT=Param
`Param`	(0~5) Battery level of remote device

+HFPNET - HFP Remote Device Network Operator Selection

Format	+HFPNET=Param
`Param`	(UTF8) Network operator selection of remote device

+HFPMANU - HFP Remote Device Manufacture

Format	+HFPMANU=Param
`Param`	(UTF8) Manufacture name of remote device

+HFPNUM - HFP Remote Device Phone Subscriber Number

Format	+HFPNUM=Param
`Param`	(ASCII) Phone subscriber number of remote device

+HFPIBR - HFP Remote Device In-band-ring Support

Format	+HFPIBR=Param
`Param`	0-No support 1-support
Description	Report whether the current connected phone support in-band-ring

+HFPRING - HFP Remote Device n-band-ring Indication

Format	+HFPRING=Param
`Param`	0-No support in-bang-ring 1-support in-band-ring
Description	The mobile phone is ringing when the call comes. If the remote mobile phone does not support in-band-ring, the module plays the local ringtone.

A2DP/AVRCP Events

+A2DPSTAT - A2DP State

Format	+A2DPSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected (4) Paused (5) Streaming

+A2DPDEV - A2DP Remote Device Information

Format	+A2DPDEV=Param1{,Param2}
`Param1`	(12 Bytes ASCII), Remote device’s MAC address of current A2DP connection
`Param2`	(UTF8), Remote device’s name of current A2DP connection

+AVRCPSTAT - AVRCP State

Format	+AVRCPSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected

+PLAYSTAT - Media Player State

Format	+PLAYSTAT=Param
`Param`	(0) Stopped (1) Playing (2) Paused (3) Fast Forwarding (4) Fast Rewinding

+PLAYMODE - Media Player Repeat/Shuffle Mode

Format	+PLAYMODE=Param1,Param2
`Param1`	Repeat Mode (1~4) (1) Off (2) Single Track (3) All Tracks (4) Group
`Param2`	Shuffle Mode (1~3) (1) Off (2) All Tracks (3) Group

+TRACKSTAT - Media Player Play Progress

Format	+TRACKSTAT=Param1,Param2,Param3
`Param1`	(0~4), Media Player State, see +PLAYSTAT
`Param2`	(Decimal ASCII),Elapsed time of current track in millisecond
`Param3`	(Decimal ASCII),Total time of current track in millisecond

Example: Read media player play progress every 1s
>> +TRACKSTAT=1,54000,322000
>> +TRACKSTAT=1,55000,322000
>> +TRACKSTAT=1,56000,322000

+TRACKINFO - Media Track Information

Format	+TRACKINFO=Param1,Param2,Param3
`Param1`	title
`Param2`	artist
`Param3`	album

Example: Phone playing song “Creep-Radio Head”

>> +TRACKINFO=Creep,Radiohead,Pablo Honey

+BROWSTAT - Media Browsing Status

Format	+BROWSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected (4) Browsing

+BROWDATA - Media Player File System Browsing Data

Format	+BROWDATA=Param1, Param2 {, Param3{, Param4}}
`Param1`	Browsing type, for each type, the following data represents:
`P`	Parame1: media player information Parame2: 0 – support browsing; 1- not support browsing Parame3: media player id Parame4: media player name
`R`	Parame1: root dictionary name Parame2: root dictionary name
`F`	Parame1: folder ID and name Parame2: folder ID Parame3: folder name
`M`	Parame1: media track ID and name Parame2: media track ID Parame3: media track name
`E`	Parame1: browsing operation result code Parame2: 0 - browsing success; other - browsing error code
Description	Please see application scenarios: AVRCP file system browsing

+BIPSTAT - BIP State

Format	+BIPSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected (4) Downloading
Description	BIP configuration files are now only used for media player cover image downloads, please see application scenarios: AVRCP album image download

+COVERART - Media Track Cover Downloaded Successfully

Format	+COVERART=Param
`Param`	Image ID
Description	The cover image is placed in the specified folder named ImageID.jpg. Please refer to the application scenario: AVRCP album image download

Phonebook Access Events

+PBSTAT - PBAP State

Format	+PBSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected (4) Downloading

+PBCNT - Phonebook Entries of Remote Device

Format	+PBCNT=Param
`Param`	Phonebook entries of remote device

+PBDATA - Phonebook Data

Format1	+PBDATA=Param1,Param2,Param3{,Param4}
`Param1`	Type (0) Phonebook (SIM Storage) (1) Phonebook (Phone Storage) (2) Received call log (3) Dialed call log (4) Missed call log
`Param2`	Name
`Param3`	Number
`Param4`	(15 Bytes ASCII), Call time if current download type is call log Format: Year(4Bytes) Month(2Bytes) Day(2Bytes) T(1Byte) Hour(2Bytes) Minute(2Bytes) Second(2Bytes). e.g. 20161012T152826 represents 2016/10/12/15/28/26
Format2	+PBDATA=E Download complete
Description	Call time may not exist for some mobile phones

Example: Download all phonebook

<< AT+PBDOWN=1

>> +PBCNT=234

+PBDATA=1 , Jack , 18219146201
+PBDATA=1 , kenan , 8613771972680
……
+PBDATA=E

Example: Download 10 dialed call log

<< AT+PBDOWN=3,10

>> +PBDATA=3 , China Mobile , 10086 , 20171013T103516

+PBDATA=3 , Jerry , 18688967507 , 20171012T152826
……
+PBDATA=E

SPP Events

Note

Because the instructions of AAP (Android Auto Protocol) are almost the same as SPP, they are:

+AAPSTAT, +AAPDATA for AAP profile

The documentation will ignore these instructions, and the default BT631D does not support this instruction.

+SPPSTAT - SPP State

Format	+SPPSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected

+SPPDATA - SPP Received Incoming Data

Format	+SPPDATA=Param1,Param2
`Param1`	Payload length
`Param2`	Payload

Example: Received data “1234567890” from remote device via SPP

<< +SPPDATA=10,1234567890

GATT Events

+GATTSTAT - GATT State

Format	+GATTSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected

+GATTDATA - GATT Received Incoming Data

Format	+SPPDATA=Param1,Param2
`Param1`	Payload length
`Param2`	Payload

Example: Received data “1234567890” from remote device via GATT

<< +GATTDATA=10,1234567890

HID Events

+HIDSTAT - HID State

Format	+HIDSTAT=Param
`Param`	(0) Unsupported (1) Standby (2) Connecting (3) Connected

Application scenarios

Profiles initializing and change parameter

The following figure shows Profile initialization and name modification

MCU change device name CARKIT reference code:

void change_name(void)
{
    uart_send("AT+NAME\r\n");
    if(uart_read("+NAME",name_buf))
    {
        if(memcmp(name_buf,"CARKIT",6))
        {
            uart_send("AT+NAME=CARKIT,0\r\n");      //defalut disable MAC address suffix
            uart_send("AT+NAME\r\n"); // read bt name
            if(uart_read("+NAME",name_buf))
            {
                if(memcmp(name_buf,"CARKIT",6))
                {
                    //change name fail
                }
                else
                {
                    //change name success
                }
            }
        }
    }
}

Sink mode connection

Note

BT631D default: AUXCFG=2,PROFILE=9387

Source mode connection

Note

The transmission(source) mode connection needs to configure the module to A2DP Source, HFP Source By default, the program will not actively enter audio transmission mode or call (intercom) mode after connecting to headphones or speakers. You need to send instructions: Start audio transmission (AT+AUDROUTE=1) Start call (AT+AUDROUTE=2)

MCU connects AirPods and starts audio transmission. Reference code:

#define PROFILE_HFP_HF              (uint16)(BIT3)
#define PROFILE_HFP_AG              (uint16)(BIT4)
#define PROFILE_A2DP_SINK           (uint16)(BIT5)
#define PROFILE_A2DP_SOURCE         (uint16)(BIT6)

void bt_connect(void)
{
    //enable hfp source,a2dp source,avrcp tg,spp,gatt
    uart_send("AT+PROFILE=339\r\n"); //if profile changes,module will auto reboot,
    wait_ms(500);
    uart_send("AT+PROFILE\r\n");
    uint32 profiles = uart_read("+PROFILE",profiles);
    if(profiles & (PROFILE_A2DP_SOURCE|PROFILE_HFP_AG))
    {
        uint8 addr[6];
        uint8 buf[30]={0};
        uint8 a2dp_state=0
        uart_send("AT+SCAN=1\r\n");
        uart_read_scan_addr("+SCAN",addr);
        sprintf(buf,"AT+A2DPCONN=%s\r\n",addr);
        uart_send(buf); //send a2dp connect

        uart_read("+A2DPSTAT",a2dp_state);
        if(a2dp_state == 3) //a2dp connected
        {
            uart_send("AT+AUDROUTE=1"); // start a2dp audio
        }
        uart_read("+A2DPSTAT",a2dp_state);
        if(a2dp_state == 5)
        {
            //a2dp streaming
        }
    }
    else
    {/*not support master*/}
}

HFP three-way call operation

Note

BT631D and other modules do not turn on the three-way calling function. If you need to test this function, please contact Feiyitong.

@startuml
hide footbox
skinparam sequenceMessageAlign center

box #LightBlue
participant Host as host
participant Blueware as bt
end box

rnote over host, bt: HFP connected

bt -> host: ...
bt -> host: +HFPSTAT=3

rnote over host, bt: Dial "10086"
host -> bt: AT+HFPDIAL=10086
bt -> host: OK
bt -> host: +HFPSTAT=4,10086 (phone dialing)
bt -> host: +HFPAUDIO=1
bt -> host: +HFPSTAT=6,10086 （call active）

rnote over host, bt: Three-way call
bt -> host: +HFPSTAT=8,10086,18620277271
host -> bt: AT+HFPMCAL=2 (Hold active call and accept another call)
bt -> host: +HFPSTAT=9,18620277271,10086 (18620277271 active,10086 hold)
host -> bt: AT+HFPMCAL=2 (Hold active call and accept another call)
bt -> host: +HFPSTAT=9,10086,18620277271 (10086 active,18620277271 hold)

host -> bt: AT+HFPMCAL=1 (Release active call and accept another call)
bt -> host: +HFPSTAT=6,18620277271 (one call active now)

rnote over host, bt: hang up the phone
host -> bt: AT+HFPCHUP
bt -> host: +HFPAUDIO=0
bt -> host: +HFPSTAT=3

@enduml

AVRCP file system browsing

Note

The BT631D module does not open this function. If you need to test this function, please contact Feitong.

AVRCP album image download

Note

Album image downloading is only supported by the vehicle protocol stack module, BT631D module does not support.

Phonebook/Contact photo download

Note

Contact photo Only supported by vehicle protocol stack module, not supported by BT631D module

Appendix

Download PDF Document

Download PDF Document

0	In simulation mode, the module will detect the internal/external codec through I2C at startup and report +CODEC=id
1	I2S Master; Sample rate=48000Hz; Resolution=16bits; Bit clock= 48000162ch=1.536Mhz
3	I2S Slave; Sample rate=48000Hz; Resolution=16bits; Bit clock= 48000162ch=1.536Mhz
65	I2S Master; Sample rate=48000Hz; Resolution=32bits; Bit clock= 48000322ch=3.072Mhz
67	I2S Slave; Sample rate=48000Hz; Resolution=32bits; Bit clock= 48000322ch=3.072Mhz
113	PCM Master; Sample rate=48000Hz; Resolution=16bits; Bit clock= 48000162ch=1.536Mhz