Function Description

Default Configuration

Based on the general BLE data transmission Application Firmware：

PIN	Status	Description
PIN 8	Low Level	Bluetooth Disconnected
PIN 8	High Level	Bluetooth Connected

Bluetooth Not Connected: Data received via UART is parsed as AT commands.
Bluetooth Connected: All data received via UART is sent as-is to the remote Bluetooth device.

Bluetooth Not Connected: Data received via UART is parsed as AT commands.
Bluetooth Connected: Data received via UART is still parsed as AT commands. Data must be sent to the remote device using AT commands, e.g., AT+LESEND.

Type	UUID	Operation	Description
Service	0xFFF0		Throughput transmission service
Write	0xFFF2	Write, Write Without Response	APP to Module
Notify	0xFFF1	Notify	Module to APP

Process	Operation	Timing	Key Signal/Response
Power On	Internal initialization completed	≥250ms	/
AT Configuration	Send AT command (e.g., `AT+NAME=FSC-BT3721V`)	Interval between commands ≥100ms	`OK` or `ERROR`

BAUD	Data Packet	Transmission Interval	Connection Interval	Transmission Method	Data Rate
460800	244	5	15ms	Notify	46000 Byte/s

The low-power function can be enabled or disabled via the command AT+LPM{=Param}.

AT+LPM=0
- Disable Low-Power Mode
AT+LPM=1
- The BT serial port will automatically enter low-power mode if no data is received for more than 5 seconds.
- The first frame of data from the BT serial port wakes up the Bluetooth.
- If the connection is successful, it will not enter low-power mode.
AT+LPM=2
- PIN20(HOST_WAKE_BT) Low level: The module enters sleep mode.
- PIN20(HOST_WAKE_BT) High level: The module exits sleep mode.
- Module sleep PIN18(BT_WAKE_HOST) Low level.
- Module wake up PIN18(BT_WAKE_HOST) High level.