User's Manual

9
HVOUT Programmable input and output port
10
HVIN Vacant
11
RESETB Low level reset, at least 5ms
12
VCC Power supply V3.3
13
GND GND
14
GND GND
15
NC
NC
16
USBDP
NC
17
USBDN
NC
18
NC Vacant
19
NC Vacant
20
NC
NC
21
GND GND
22
GND GND
23
GPIO26 Disconnect pin (200ms low electrical pulse off)
24
GPIO28
LED light pin (unconnected flashing, connection
is always on)
25
GPIO23
Bluetooth connection indicator (not connected
low, connection high)
26
GPIO25
AT command switch pin (low AT command
mode)
27
SCL NC
28
SDA
NC
29
GPIO24 Programmable input and output port
30
GPIO27 Programmable input and output port
31
GPIO28 Programmable input and output port
32
GND GND
33
GND GND
8．Detailed description of function pins:
1、 P24 pin (GPIO28): LED indicator pin
·Used to indicate the status of the Bluetooth module. Correspondence between the LED
flashing mode and the Bluetooth module status is shown in the following table:
LED display
Module status
Uniformly slow flashing (800ms-on, 800ms-off) standby mode
always brigh
Connection Status
2. P26 pin (GPIO25): AT command switching pin
Pin status Module status
Connect to GND Enter AT command mode