Module model: SJR-BTM525

• Bluetooth chip: QCC5125, built-in 32M SPI FLASH
• Bluetooth version: 5.1
• Module size: 13mm x 18mm x 2.5mm
• Power supply voltage: 3.0-4.3v

Data link (Bluetooth module specification, reference schematic diagram):

http://www.tianjiarun.com/search.php?q=BTM525

Default firmware:

1. Support sbc, aac, aptx, aptx-LL, aptx-HD, aptx-adaptive decoding, no call function, optional I2S, SPDIF, analog output

2. Button description:

● SYS_CTRL: high level power on, low level power off, automatically enter pairing mode when power on

● PIO2: Short press to pause playback, long press for 3 seconds to enter pairing, long press for 5 seconds to clear the pairing record

● PIO3: Short press the previous song, long press the volume down

● PIO4: short press next song, long press volume up

● PIO5: connected to high level, not connected to low level

● PIO19: There is audio output high level, no audio low level

● PIO20: SPDIF output port

3. Indicator light description:

● Bluetooth is not connected: LED0 and LED1 flash alternately

● Bluetooth is connected: LED1 is always on

● Bluetooth audio playback: LED1 is always on

Note: The use of the usb sound card must be connected to the four wires of the module, USBDP, USBDN, VCHG, GND