Flyron FN-BC04 User manual

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
1
FN-BC04 MP3 Sound Module with 10W Amplifier
User’s Manual
V1.1
Contents
1. Overviews …………………………………………………………..………………….................2
1.1. Brief introduction ………………………………………………………………………………………... 2
1.2. Features …………………………………………………………………………………………………. 2
1.3. Technical parameters .................................................................................................................. 2
2. Connections ..........................................................................................…….......................2
3. Button Control Mode .................................................………………………………..............3
3.1. Trigger Mode Selection...................................................................................................................3
3.2. Audio Files Loading.........................................................................................................................5
4. Serial Control Mode ……………………………………………………………………...............6
4.1. Naming Rules o Audio Files and Folders ….. …………………………………………………….....6
4.2. Command Format..........................................................................................................................6
4.3. About Checksum ………………………………………………………………………………..………...7
4.4. Serial Communication Commands .................................................................................................7
4.5. Returned Data from Module ………….…………………………………………………….…………...10
4.6. Detailed Annotation of Control Commands ...................................................................................12
4.7. Detailed Annotation of Query Commands ....................................................................................16
4.8. About Delay of Serial Programming ..............................................................................................17

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
2
1. Overviews
1.1. Brief Introduction
FN- BC04 is a high quality MP3 sound module developed by Flyron Technology Co., Ltd. Equipped with an on-
board 10W amplifier, the sound module can be controlled by 4 separate buttons hooked up to the ‘one-on-one’
inputs terminals and by UART R232 serial port working with a MCU. Great audio output, industry-grade design
and strong anti-jamming capability make it possible to be used for many different applications.
1.2. Features
1). With high quality audio decoder, supports MP3 and WAV audio formats.
2). Sampling rates supported: 8/11.025/12/16/22.05/24/32/44.1/48(KHz).
3). 24 bit DAC output and supports dynamic range 90dB and SNR 85dB.
4). Supports one-on-one 4 button trigger control mode and RS232 serial port control mode.
5). In button control mode, it plays back 4 sounds one-on-one by negative triggering.
6). Uses micro SD card and the built-in SPI flash memory for storage devices.
7). Built-in 4MB SPI flash memory by default, and supports max. 16MB.
8). Supports max. 32GB micro SD card.
9). Possible to load audio files to the flash memory directly via the micro USB connecting with computer like
using a USB flash drive.
10). Equipped with a mono 10 watts amplifier that can drive a 10 watts speaker directly.
11). Equipped with a 3.5mm audio jack for stereo output that can drive an earphone directly or connect with an external amplifier.
12). Adjustable sound volume with the potentionmeter.
13). Wide range for power input(DC8-24V).
14). PCB size: 52mmx49mm
1.3. Technical Parameters
1). Working voltage: DC 8V-24V
2). Working current: ≤400mA (Input: DC12V)
3). Power Consumption: ≤10W
4). On-board flash memory size: 4MB
5). Audio format: MP3 and WAV
2. Connections
K1, K2, K3 and K4 are representing Normally Open (N.O.) manual buttons. TX port and RX port are used to connect with a MCU,
through which sending serial commands to control the module. Please refer to the connection example below.

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
3
K1 K2 K3 K4
3. Button Control Mode
3.1. Trigger Mode Selection
In button control mode, there are 4 trigger modes available for users to choose according to the actual needs. Any of these 4
trigger modes can be set/acquired through a configuration file named “read.cfg”, which comes from a text file(.txt) originally.
Users just need to fill in a digit/parameter that is corresponding to a trigger mode in a new built text file. Save it and rename it
“read.cfg”, then put it in the root directory of the micro SD card or the flash memory together with the 4 audio files. Please
refer to the sheet below about the digits and the associated trigger modes.
GND
TX port
RX port
10W/8ohms
speaker
DC8-24V
input
Spare GND

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
4
Pulse interruptible one-on-one playback: In this mode, a single negative pulse will start playback.It is
possible to interrupt the playback by pressing the same button used to activate. Once playback is
interrupted, it will automatically restart the audio file immediately. It’s also possible to interrupt the play
back by pressing any of the other 3 buttons. Once playback is interrupted, it will automatically start the
sound that is associated with the button pressed.
Level hold loop playback: In this mode, the negative pulse must be held/maintained to the sound module
trigger for audio file to complete. The audio file will only playback while button, or negative pulse, is
held/maintained during playback. Once the button being held, or negative pulse, is removed, the playback
will be stopped/cancelled. Once the button is kept holding, when the playback of the audio file is finished, it
will start to play it repeatedly(loop playback).
Pulse non-interruptible one-on-one playback: In this mode, a single negative pulse will start playback.It's
not possible to interrupt the playback by pressing the same button or the other buttons. Once an audio file
is triggered, the audio file will not be able to be interrupted/cancelled during playback. The playback will
only end when the audio file has played its entirety.
Standard MP3 key mode playback: In this mode, the buttons between K1 and K4 will be functioned as
Previous, Next, Play/pause, and Stop respectively. In this case not like the other 3 trigger modes above,
more than 4 audio files can be placed.
For example, if the trigger mode of level hold loop playback is needed, firstly build a new TXT file on the computer, and simply
enter the digit “1” as below, and save the file.
Digit in file “read.cfg”
Corresponding Trigger Mode
0
Pulse interruptible one-on-one playback
1
Level hold loop playback
2
Pulse non-interruptible one-on-one playback
3
Standard MP3 key mode playback

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
5
And change the file name “xxx.txt” to “read.cfg” as below, then the configuration file with level hold loop playback mode is
made successfully.
3.2. Audio Files Loading
4 audio files need to be directly stored in the root directory of the SD card or the on-board flash memory. No folders can be
in the ‘root directory’. The arrangements of the audio files are managed by a physical indexing sequence. In other words, the
file that is to be loaded first in the storage device will be associated with input “K1”. The last file to be loaded in the storage
device will be associated with input “K4”. In order to guarantee a correct ‘one-on-one’ order, please refer to the following
steps.
1). Build a new folder on the computer and put the 4 audio files in this new folder.
2). Rename the audio files from 001.mp3/wav to “004.mp3/wav”, and make sure they are ranked from “001.mp3/wav” to
“004.mp3/wav” in order.
3). Plug in your SD card on computer or connect the module with computer through the micro USB(make sure the SD card or
the on-board flash memory is empty).
4). Format the SD card into FAT or FAT32 or format the on-board flash into FAT.
5). Select all of the 4 audio files in the folder.
6). Right click on the first file (001.mp3/wav) and choose "Send to removable disk".
7). This should send the 4 audio files to the SD card or the on-board flash memory in a correct sequence.
8). Put the configuration file with the trigger mode needed into the root directory together with audio files as below, then
refresh.

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
6
9). Safely remove the SD card and insert it onto the module or disconnect the flash memory of the module from computer.
10). Apply power to the module and push any of 4 buttons to play back a corresponding sound.
Notes:. 1). If the trigger mode of pulse interruptible one-on-one playback is needed, it’s also workable if you don’t put
the configuration file. The module takes this trigger mode as the default if without a configuration file.
2). When the SD card is plugged/inserted into the module. Only audio files from the SD card will be played.
4. UART RS232 Serial Control Mode
Serial control mode is provided for users who want to use a MCU to control this module. It’s more flexible and is
able to realize many more functions to control this module via serial serial commands through the ports TX and RX
on the module..
4.1. Naming Rules of Audio Files and Folders
1). Audio files directly stored in the root directory of the storage device(micro SD card or the flash memory) need to be renamed as
0001.mp3/0001.wav, 0002.mp3/0002.wav, 0003.mp3/0003.wav, .......3000.mp3/3000.wav(If there are more than 10 files, storing
them in the micro SD card instead of the flash memory is suggested).
Here it works according to physical sequence when you copy the files from computer to SD card or SPI flash. For example,
when the module receives a command to play the track 0001.mp3, it will play the 1st track you copied from computer, probably
0001.mp3 or not (maybe it would play 0007.mp3 if it was the first one you copied from computer). In order to avoid this problem,
when you make the copy, rename the audio files firstly on computer and put all the renamed files in a one folder, then press
“Ctrl+A” on the key board to select all, and press “Ctrl+C” to copy, and go back to the SD card or the SPI flash, and press
“Ctrl+V” to past all the files into the SD card or SPI flash. Or users just directly give up this way and just move the audio files to
folders and choose to control and play them in a folder as below.
2). Ordinary folders must be renamed as 01, 02, 03......99, and the audio files must be renamed as 001.mp3/001.wav,
002.mp3/002.wav, 003.mp3/003.wav, .......255.mp3/255.wav. It is also possible to keep the original name when you rename a file.
For example, the original name is “Yesterday Once More.mp3”, then you can rename it as “001Yesterday Once More.mp3”.
Note: In addition, there are two special purposed folders “MP3” and “ADVERT” that can be chosen by users to use or not
according to the actual needs. Audio files stored in these two folders need to be renamed as 0001.mp3/0001.wav,
0002.mp3/0002.wav, 0003.mp3/0003.wav, .......3000.mp3/3000.wav.
4.2. Command Format
Communication baud rate: 9600 bps
Data bits: 1
Checkout: none
Flow Control: none

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
7
Format: $S / Ver. / Number / Command / Feedback / Param_MSB / Param_LSB / Check_MSB / Check_LSB / $O
$S
Start byte 0x7E
Ver.
Version byte, 0xFF by default
Number
Number of bytes from version info to Check_LSB, typically 0x06 (checks um not counted)
Command
Command byte
Feedback
0x01: Need feedback --send confirmation back to MCU; 0x00: No need feedback
Param_MSB
Most significant byte of parameter
Param_LSB
Least significant byte of parameter
Check_MSB
Most significant byte of checksum
Check_LSB
Least significant byte of checksum
$O
End byte 0xEF
For example, if we specify playback of SD card, we need to send the command “7E FF 06 09 00 00 02 FF F0 EF”. The number
is 6 bytes, and these 6 bytes are “FF 06 09 00 00 02”. Start byte, end byte and checksum are not counted.
4.3. About Checksum
Regarding to calculating checksum, you can use the following formula to count.
Checksum (2 bytes) = 0xFFFF–(CMD + Feedback + Para_MSB + Para_LSB) + 1
Normally it’s okay whether users choose to use checksum or not, our module can receive a serial data with or without checksum,
but some of users use a MCU without crystal oscillator, so if in that case we strongly suggest users to add checksum to make sure
the communication stability.
4.4. Serial Communication Commands
4.4.1. Control commands
Command
Function
Note
0x01
Play Next
0x02
Play Previous
0x03
Specify playback of a track
See 4.6.1 for details
0x04
Increase volume
0x05
Decrease volume
0x06
Specify volume
See 4.6.2 for details
0x08
Specify single repeat playback
See 4.6.3 for details
0x09
Specify playback of a device
See 4.6.4 for details
0x0A
Set sleep mode
See 4.6.5 for details
0x0B
Awake from sleep
0x0C
Reset

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
8
0x0D
Play
0x0E
Pause
0x0F
Specify playback of a track in a folder
See 4.6.6 for details
0x13
Inter-cut an advertisement
See 4.6.7 for details
0x14
N/A (reserved)
0x15
Stop playing inter-cut advertisement
See 4.6.8 for details
0x16
Stop
0x17
Specify repeat playback of a folder
See 4.6.9 for details
0x18
Set random playback
See 4.6.10 for details
0x19
Set repeat playback of current track
See 4.6.11 for details
0x22
Specify playback of a track with a specific volume level
See 4.6.12 for details
4.4.2. Examples of sending control commands
Command Description
Serial Commands
[with checksum]
Serial Commands
[without checksum]
Note
Play Next
7E FF 06 01 00 00 00 FE FA EF
7E FF 06 01 00 00 00 EF
Play Previous
7E FF 06 02 00 00 00 FE F9 EF
7E FF 06 02 00 00 00 EF
Specify playback of a track
(in the root directory)
7E FF 06 03 00 00 01 FE F7 EF
7E FF 06 03 00 00 01 EF
Specify playback of the 1st track
7E FF 06 03 00 00 02 FE F6 EF
7E FF 06 03 00 00 02 EF
Specify playback of the 2nd track
7E FF 06 03 00 00 0 A FE EE EF
7E FF 06 03 00 00 0 A EF
Specify playback of the 10th track
Increase volume
7E FF 06 04 00 00 00 FE F7 EF
7E FF 06 04 00 00 00 EF
Decrease volume
7E FF 06 05 00 00 00 FE F6 EF
7E FF 06 05 00 00 00 EF
Specify volume
7E FF 06 06 00 00 1 E FE D7 EF
7E FF 06 06 00 00 1 E EF
Specified volume is level 30
Specify single repeat
playback (in the root
directory)
7E FF 06 08 00 00 01 FE F2 EF
7E FF 06 08 00 00 01 EF
Repeatedly play the 1st track
7E FF 06 08 00 00 02 FE F1 EF
7E FF 06 08 00 00 02 EF
Repeatedly play the 2nd track
7E FF 06 08 00 00 0 A FE E9 EF
7E FF 06 08 00 00 0 A EF
Repeatedly play the 10th track
Specify playback of a
7E FF 06 09 00 00 02 FE F0 EF
7E FF 06 09 00 00 02 EF
Specified device is SD card
device
7E FF 06 09 00 00 04 FE EE EF
7E FF 06 09 00 00 04 EF
Specified device is on-board SPI flash
Set sleep mode
7E FF 06 0 A 00 00 00 FE F1 EF
7E FF 06 0 A 00 00 00 EF
Awake from sleep
7E FF 06 0B 0 0 0 0 00 FE F0 EF
7E FF 06 0B 0 0 0 0 00 EF
Reset
7E FF 06 0C 00 00 00 FE EF EF
7E FF 06 0C 00 00 00 EF
Play
7E FF 06 0D 00 00 00 FE EE EF
7E FF 06 0D 00 00 00 EF
Pause
7E FF 06 0E 0 0 0 0 00 FE ED EF
7E FF 06 0E 0 0 0 0 00 EF
Specify playback of a track
in a folder
7E FF 06 0 F 00 01 01 FE E A EF
7E FF 06 0 F 00 01 01 EF
Specify track "001" in the folder “01”
7E FF 06 0 F 00 01 02 FE E9 EF
7E FF 06 0 F 00 01 02 EF
Specify track "002" in the folder “01”

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
9
Inter-cut an advertisement
7E FF 06 13 00 00 01 FE E7 E F
7E FF 06 13 00 00 01 EF
Inter-cut track "0001" in the folder
“ ADVERT”
7E FF 06 13 00 00 02 FE E6 EF
7E FF 06 13 00 00 02 EF
Inter-cut track "0002" in the folder
“ADVERT”
7E FF 06 13 00 00 FF FD E9 EF
7E FF 06 13 00 00 FF EF
Inter-cut track "0255" in the folder
“ADVERT”
Stop playing inter-cut
advertisement
7E FF 06 15 00 00 00 FE E6 EF
7E FF 06 15 00 00 00 EF
Go back and continue to play the
music interrupted
Stop
7E FF 06 16 00 00 00 FE E5 EF
7E FF 06 16 00 00 00 EF
Stop all playback tasks
Specify repeat playback of a
folder
7E FF 06 17 00 02 00 FE E2 EF
7E FF 06 17 00 02 00 EF
Specify repeat playback of the folder
“02”
7E FF 06 17 00 01 00 FE E3 EF
7E FF 06 17 00 01 00 EF
Specify repeat playback of the folder
“01”
Set random playback
7E FF 06 18 00 00 00 FE E3 EF
7E FF 06 18 00 00 00 EF
Random playback of the whole
device
Set repeat playback of
current track
7E FF 06 19 00 00 00 FE E2 EF
7E FF 06 19 00 00 00 EF
Turn on single repeat playback
7E FF 06 19 00 00 01 FE E1 EF
7E FF 06 19 00 00 01 EF
Turn off single repeat playback
Specify playback of a track
with a specific volume level
7E FF 06 22 00 1 E 01 FE B A EF
7E FF 06 22 00 1 E 01 EF
Play 1st track with volume level 30
7E FF 06 22 00 0 F 02 FE C8 EF
7E FF 06 22 00 0 F 02 EF
Play 2nd track with volume level 15
4.4.3. Query commands
Command
Function
Note
0x3F
Query current online storage device
See 4.7.1 for details
0x40
Module returns an error data with this command
0x41
Module reports a feedback with this command
0x42
Query current status
See 4.7.2 for details
0x43
Query current volume
0x48
Query number of tracks in the micro SD Card
0x49
Query number of tracks in the SPI flash
0x4C
Query current track in the micro SD Card
0x4D
Query current track in the SPI flash
0x4E
Query number of tracks in a folder
See 4.7.3 for details
0x4F
Query number of folders in the current storage device
See 4.7.4 for details
4.4.4 Examples of sending query commands

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
10
Command Description
Serial Commands
[with c heck sum]
Serial Commands
[without c heck sum]
Notes
Query current online storage
device
7E FF 06 3F 00 00 00 FE BC EF
7E FF 06 3F 00 00 00 EF
Query current status
7E FF 06 42 00 00 00 FE B9 EF
7E FF 06 42 00 00 00 EF
Query current volume
7E FF 06 43 00 00 00 FE B8 EF
7E FF 06 43 00 00 00 EF
Query number of tracks in the
micro SD card
7E FF 06 48 00 00 00 FE B3 EF
7E FF 06 48 00 00 00 EF
Total file numbers of
current device
Query number of tracks in the
SPI flash
7E FF 06 49 00 00 00 FE B2 EF
7E FF 06 49 00 00 00 EF
Total file numbers of
current device
Query current track in the micro
SD card
7E FF 06 4C 00 00 00 FE AF EF
7E FF 06 4C 00 00 00 EF
Query the track being
played
Query current track in the SPI
flash
7E FF 06 4D 00 00 00 FE AE EF
7E FF 06 4D 00 00 00 EF
Query the track being
played
Query number of tracks in a
folder
7E FF 06 4E 00 00 01 FE AC EF
7E FF 06 4E 00 01 00 EF
Query number of folders in the
current storage device
7E FF 06 4F 00 00 00 FE AC EF
7E FF 06 4F 00 00 00 EF
4.5. Returned Data from Module
4.5.1. Returned data after the module is powered on
1) After the module is powered on, normally it needs about no more than 500ms to 1500m s (depending on the actual track
quantities in the storage device) initialization time. Once the initialization is done, the module returns a data to MCU. If it
does not return a data after more than the initialization time, it means there is an error for initialization, and please check
the hardware connections.
2) The returned data from module after initialization means the current effective storage device /online equipment. For
example, the module returns 7 E FF 06 3F 00 00 02 xx xx EF. 0x3F is the returned command by module, and 0x02
represents SD card is effective online. See the details as below.
Online Equipment Re turned Data
SD card online
7E FF 06 3F 00 00 02 xx xx EF
PC online
7E FF 06 3F 00 00 04 xx xx EF
SPI flash online
7E FF 06 3F 00 00 08 xx xx EF
3) MCU cannot send commands to control the module until the initialization of the module is done and a data is returned,
otherwise the commands sent by MCU will be ignored and also this will effect initializing of the module.
4.5.2. Returned data after a track is finished playing
Track Played
Returned Data
1st track is finished playing in SD card
7E FF 06 3D 00 00 01 xx xx EF
2nd track is finished playing in SD card
7E FF 06 3D 00 00 02 xx xx EF

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
11
1st track is finished playing in SPI flash
7E FF 06 3E 00 00 01 xx xx EF
2nd track is finished playing in SPI flash
7E FF 06 3E 00 00 02 xx xx EF
1) There is a returned data after a track is finished playing. For example, the returned data is 7E FF 06 3D 00 00 01 xx xx EF.
0x3D represents SD card and 0x3E represents SPI flash. 0x00 and 0x01 represents the 1st track. 0x01 and 0xF4 represents
the 500th track (0x01F4=500).
2) Because all of the files (tracks) in the storage device are read in physical sequence, the returned data still follow the physical
sequence, which needs to be noted.
4.5.3. Returned data of feedback from module
Module returns ACK 7E FF 06 41 00 00 00 xx xx EF
1) In order to enhance stability between data communication, the function of a feedback from module is added. Once there is a
feedback to MCU from the module, it means the module has successfully received the command that MCU sent out. 0x41 is
the returned command by module.
2) Users are free to choose this feedback or not. It’s also fine not to choose this function.
4.5.4. Returned data of errors
Returned Data of Errors
Meaning Description
7E FF 06 40 00 00 01 xx xx EF
Module busy (this info is returned when the initialization
is not done)
7E FF 06 40 00 00 02 xx xx EF
Currently sleep mode (supports only specified device in
sleep mode)
7E FF 06 40 00 00 03 xx xx EF
Serial receiving error (a frame has not been received
completely yet)
7E FF 06 40 00 00 04 xx xx EF
Checksum incorrect
7E FF 06 40 00 00 05 xx xx EF
Specified track is out of current track scope
7E FF 06 40 00 00 06 xx xx EF
Specified track is not found
7E FF 06 40 00 00 07 xx xx EF
Inter-cut error (an inter-cut operation only can be done
when a track is being played )
7E FF 06 40 00 00 08 xx xx EF
SD card reading failed (SD card pulled out or damaged)
7E FF 06 40 00 00 0A xx xx EF
Entered in to sleep mode
When the module is powered on, it reads SD card first and if SD card is not available it goes to SPI flash.
4.5.5. Returned data after a storage device is plugged in or pull out
Status
Re turned Data

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
12
SD card is plugged in
7E FF 06 3A 00 00 02 xx xx EF
USB cable connected to PC is plugged in
7E FF 06 3A 00 00 04 xx xx EF
SD card is pulled out
7E FF 06 3B 00 00 02 xx xx EF
USB cable connected to PC is pulled out
7E FF 06 3B 00 00 04 xx xx EF
0x3A represents a device is plugged in while 0x3B represents a device is pull out. 0x02, 0x04 represent SD card and USB cable
connected to PC respectively.
4.6. Detailed Annotation of Control Commands
4.6.1. Specify playback of a track (in the root directory of the storage device)
The available selectable tracks are from 1st to 3000th in the root directory of the storage device. Actually it can support more, but if
we make it support more, the operation speed will become slow. Usually most of applications do not need to support much more
files. Normally if the total track quantity is less than 1,000 in the storage device the response speed of the module is quicker than
50ms. If the total track quantity is more than 1000 the response speed is a little slower than 100ms.
1) For example, if set the first track to be played, send the command 7E FF 06 03 00 00 01 FE F7 EF
7E -- - Start byte
FF -- - Version Information
06 --- Number of bytes
03 --- Actual command (specify playback of a track)
00 --- 0 x01 : need feedback ; 0 x00 : no need feedback
00 --- Most significant byte of the track (MSB of Parameter)
01 --- Least significant byte of the track (LSB of Parameter) FE --- Most significant byte of checksum
(MSB of checksum) F7 - -- Least significant byte of checksum (LSB of checksum ) EF --- End byte
0xEF
2) Regarding track selection, if the 100th song (track) is selected to be played, firstly convert 100 to
hexadecimal. It is double-byte by default, i.e. 0 x006 4. MS B=0 x00 ; LS B=0 x64
4.6.2. Specify volume
1) Our system power-on default volume is level 30, if you want to set the volume, then directly send the
corresponding command.
2) For example, if specify the volume to level 15, send the command 7E FF 06 06 00 00 0F FF D5 EF.
3) MSB=0x00; LSB=0x0F, 15 is converted to hexadecimal 0x000F.
4.6.3. Specify single repeat playback (in the root directory of the storage device)
Repeatedly play 1st track
7E FF 06 08 00 00 01 xx xx EF
Repeatedly play 2nd track
7E FF 06 08 00 00 02 xx xx EF

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
13
Repeatedly play 3rd track
7E FF 06 08 00 00 03 xx xx EF
During single repeat playback, you can still normally execute the operations Play/Pause, Previous, Next, Volume +/-
and repeat playback. Users can specify single track playback or send the stop command to turn off single repeat
playback status.
4.6.4 Specify playback of a device
Specify playback of SD card
7E FF 06 09 00 00 02 FE F0 EF
Specify playback of SPI flash
7E FF 06 09 00 00 04 FE EE EF
1) The module supports two types of playback devices (micro SD card and on-board SPI flash).
2) It automatically enters into the standby status after specifying a device, waiting for MCU to specify a track
to play. It takes about 200ms from specifying device to the module finishes initialization of file system.
Please wait for 200ms and then send the specified command to play a track.
4.6.5. Set sleep mode, awake from sleep and reset
Set sleep mode
7E FF 06 0A 00 00 00 FE F1 EF
Awake from sleep
7E FF 06 0B 00 0 0 00 FE F0 EF
Reset
7E FF 06 0C 00 00 00 FE EF EF
1) After set the module enter into sleep mode, there is also other two ways other than sending the command
to awake the module.
a. Specify playback of the storage device, either SPI flash or SD card.
b. Pull out the storage device and re-plug it in.
2) The reset is a soft reset. The reset time is 5-8 seconds. This allows the reset command under any status.
Note: When the module enters into the sleep mode, the standby power consumption is about 10mA. If users are very strict
to the power consumption, you can use a MOS and a transistor to control power supply of the module. It is possible to cut
off the power supply completely when standby is not necessary. Please refer to the schematic as below.

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
14
4.6.6. Specify playback of a track in a folder
Specify playback of track 001 in the folder 01
7E FF 06 0F 00 01 01 xx xx EF
Specify playback of track 100 in the folder 11
7E FF 06 0F 00 0B 64 xx xx EF
Specify playback of track 255 in the folder 99
7E FF 06 0F 00 63 FF xx xx EF
1). The default folders are named as "01", "11", “99” in this way. In order to be with a better system stability, it is made to support
maximum 99 folders and maximum 255 tracks in each folder..
2). For example, if specify to play “100.mp3” in the folder "01", send the command 7E FF 06 0F 00 01 64 xx xx EF
MSB: represents the name of the folder, maximum supports 99 folders from 01 - 99.
LSB: represents the track, maximum supports 255 tracks from 0x01 to 0xFF.
3). You must specify both the folder and the file name to target a track. This feature supports MP3 and WAV audio formats.
4). The following two images illustrates the naming method of folders and files.
4.6.7. Inter-cut an advertisement
Inter-cut track "0001" in the folder “ADVERT”
7E FF 06 13 00 00 01 FE E7 EF
Inter-cut track "0002" in the folder “ADVERT”
7E FF 06 13 00 00 02 FE E6 EF
Inter-cut track "0255" in the folder “ADVERT”
7E FF 06 13 00 00 FF FD E9 EF
Inter-cut track "1999" in the folder “ADVERT”
7E FF 06 13 00 07 CF FE 12 EF
Inter-cut track "3000" in the folder "ADVERT”
7E FF 06 13 00 0B B8 FE 25 EF
1) This module supports inter-cut advertisements during playback of a track, so that it can meet some special
needs for some applications.
2) After sending the command 0x13, the system will save the ID V3 information of the track being played and
pause, and then it will play the specified inter-cut track (advertisement). When the inter-cut track is finished,
the system will go back and continue to play the track that was interrupted until to the end.
3) The setting method is build a folder named “ADVERT” in the storage device and put the tracks (ads) you
need in the folder and name the files as “0001 .mp3/wav”, 0002.mp3/wav.
4) If you send an inter-cut command when the module is at Pause status or Stop status, it will not work and
there will be returned error information. In the course of an inter-cut, you can continue to intercut the other
tracks (ads). When the last inter-cut track goes to the end, the systems till goes back to the ID V3 position

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
15
saved at the first time.
4.6.8. Stop
Stop playing inter-cut advertisement
7E FF 06 15 00 00 00 FE E6 EF
Stop
7E FF 06 16 00 00 00 FE E5 EF
During playback of the module, there are two modes to stop. One is to stop playing the inter-cut advertisement, and go back and
continue to play the music interrupted and the other mode is to stop all playback (stop decoding). For example, suppose the
module is playing an inter-cut advertisement and now if send a stop command 0x16, it will stop all playback tasks.
4.6.9. Specify repeat playback of a folder
Specify repeat playback of the folder “02”
7E FF 06 17 00 00 02 FE E2 E F
Specify re pea t playback of the folder “01”
7E FF 06 17 00 00 01 FE E3 E F
The folder names must be 01- 99, and no more than 99. After sending the command, it repeatedly plays the tracks in the specific
folder and it will not stop until it receives a command to stop.
4.6.10. Set random playback
Random playback of the whole s to rage de vice 7E FF 06 18 00 00 00 FE E3 EF
This command is used to randomly play all of the tracks in the storage device according to physical sequence and no matter if
there is a folder or not in the device.
4.6.11. Set repeat playback of current track
Turn on single repeat playback
7E FF 06 19 00 00 00 FE E2 EF
Turn off single repeat playback
7E FF 06 19 00 00 01 FE E1 EF
During playback, send the turn-on command, and it will repeatedly play the current track. If the module is at Pause or Stop status,
it will not respond to this command. If you need to turn off repeat playback, just send the turn-off command.
4.6.12. Specify playback of a track with a specific volume level (in the root directory)
Play 1st track at volume level 30
7E FF 06 22 00 1E 01 FE BA EF
Play 2nd track at volume level 15
7E FF 06 22 00 0F 02 FE C8 EF
1) This function is added to meet some users’ needs to play a track at a specific volume level with one
command only, but this only can be executed for the tracks in the root directory of the storage device. The
command is 0x22.

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
16
2) For normal operations, users still need to send the volume command first and then specify playback of a
track with the corresponding command like most of MP3 players.
4.7. Detailed Annotation of Query Commands
4.7.1. Query current online storage device
Query current online storage device 7E FF 06 3F 00 00 00 FE BC EF
When the module is working, users can use the command as above (0x3F) to query the status of the online storage devices. For
example, if the module returns the data 7E FF 06 3F 00 00 0A xx xx EF, LSB 0x0A (0000 1010) represents SD card online. If LSB
is 0x1F (0000 1111), it represents both of SD card and PC online (PC online means module is connecting with PC via a USB
cable).
4.7.2. Query current status
Query current online storage device 7E FF 06 42 00 00 00 FE B9 EF
1).There are 4 status (playing, paused playing, stopped playing and in sleep) that can be queried during the
module is decoding. Users can query the current status via sending the command as above (0 x42)
2). Interpretation of returned data
Returned Data
Status
7E FF 06 42 00 02 01 xx xx EF
SD card is being played
7E FF 06 42 00 02 02 xx xx EF
SD card is paused playing
7E FF 06 42 00 08 00 xx xx EF
SPI flash is stopped playing
7E FF 06 42 00 10 00 xx xx EF
Module in sleep
3). MSB and LSB Representations
MSB Representation
LSB Representation
0x02
SD card
0x00
Stopped
0x08
SPI flash
0x01
Playing
0x10
Module in sleep mode
0x02
Paused
4.7.3. Query number of tracks in a folder
Query number of tracks in folder 01
7E FF 06 4E 00 00 01 FE AC EF
Query number of tracks in folder 11
7E FF 06 4E 00 00 0B FE A2 EF

www.flyrontech.com
E-mail: [e-mail]
Flyron Technology Co., Ltd. FN-BC04 MP3 Sound Module with 10W Amplifier
17
If the folder queried is empty without any files, the module will report an error and the data 7E FF 06 40 00 00 06 FE B5 EF will be
returned.
4.7.4. Query number of total folders in current storage device
Query number of total folders in current storage device 7E FF 06 4F 00 00 00 FE AC EF
Users can query this through sending the command above. This just supports to query the folder numbers in the root directory of
the device. Not possible to query the sub-folder numbers (Please do not build any sub-folders in a folder).
4.8. About Delay of Serial Programming
1). After the module is powered on, it needs about 500ms to 1500ms (depending on the track quantities in the
storage device) to initialize. After that, some data related to initialization returns to MCU. Users can choose to
ignore these data.
2). After specifying playback of a device (SD card or SPI flash), it needs 200ms delay before sending the
command to execute the relative operation.
3). The module processes a serial data per 10ms, so when MCU continuously sends commands one by one,
20ms delay must be added before sending next command, otherwise the command MCU sends out will not
be executed.
4). If specifying playback of a track in a folder, the delay must be longer than 40ms, as it needs time to target a
track in a folder. And even so song as sending the commands related to query a track or a folder, 40ms delay
is required.