Pin No.
Pin name
Pin
direction
Use
1
VBAT
Input
External 3.3V power supply
2
USB
Input
USB 5V power supply
3
+5V
Input
External 5V power supply, same as USB
4
RESET
Input
Reset pin
5
P10
Input
Test the P10 pin, press it for low level
6
VCC
-
Two alternative power supply modes: USB / 5V and VBAT
7
RX
Input
Serial data input
8
TX
Output
Serial data output
9
PWM2
Output
Output PWM2, connected to PWM LED
10
DISC
Input
Default pull-up input, the jumper cap is connected, and a
falling edge is generated, that is, the connection is
disconnected
11
MODE
Input
Low level switches to AT command mode, high level
switches to data transparent transmission mode (effective
when connected)
）
2.2 Function test
Test function
Description
Transparent
transmission
test
The module acts as a slave, and a mobile phone, computer or other host module acts as a
master to establish a Bluetooth master-slave connection to achieve transparent data
transmission.
1. The module is connected to the computer USB. The 6-pin jumper cap is selected to be
powered by USB. The 7-pin-RX and 8-pin-TX pins are respectively shorted with jumper
caps, MOD, DISC is floating;
2. The module is connected to the computer USB interface, the power indicator is always
on, the STAT indicator flashes at 1HZ, and the module is powered on normally. The module
automatically enters the broadcast (BLE) or query scan status (SPP). After the host initiates
the connection and establishes the connection, the STAT and LINK LED are always on,
indicating that the Bluetooth connection is successful.
3. Open the serial port, the default baud rate is 115200, the data bit is 8, 1 stop bit, no parity
bit, no flow control.
Disconnect
1. Establish a Bluetooth connection by according to transparent transmission test.
2. After the module is connected, the jumper cap is shorted to pin 10, that is, DISC, and the
connection is disconnected
Parameter
modification
1.The module is in the configuration mode when it is not connected, and the MODE pin is
left floating.
2. Pull the MODE pin low to establish a connection and at this time it is in AT command
