Function:
This module supports Bluetooth 4.1. It supports automatic link back function, WAV+APE+FLAC+MP3 lossless decoding, stereo output, and TF slot. It can insert TF card, support U disk and play TF card.

Button Description:
MODE: "Short Press" can switch TF card, U disk and Bluetooth mode.
P/P: "Short Press", Play/pause
NEXT/V+: "Short Press" is the next song, and "Short Press" is the volume increase.
PREV/V+: "Short Press" is the last song, and "Long Press" is the volume reduction.
RPT: Short Press for Mono/Loop Switching

Operation Manual:
1. Mode control: When the decoder board has no U disk or TF card, the default mode is Bluetooth when the module is powered on. When the decoder board is plugged in with U disk or TF card, the default mode of module power-on is music mode.
2. Music mode: When you insert a U disk or TF card, you can play the music files stored in it.
3. Bluetooth mode: In this mode, the telegraph will insert the English "then Bluetooth device is ready to pair" to show that it has entered the Bluetooth mode and waits for a matching connection; the mobile phone opens the Bluetooth search for "HW-BT" and connects; when the connection is successful, the decoder board will have an English prompt "the Bluetooth decvice is connected succesfully", and then the decoder board can play music.

Tips:
1. If the U disk is playing, it is recommended to use USB 5V power supply (not 3.7V lithium battery power supply), because the early U disk does not support 3.3V voltage.
2. U disk or TF card, decoding only supports FAT16/FAT32 file system, not NTFS.