User Manual
HLK-B40
Pins
Symbol.
IO
Type
Functions
25
PA4
O
Bluetooth connection status output,
high: not connected, low: connected
26
PA5
O
Current operating mode output, high: master,
low: slave
27
LED
-
Keep the functionality
28
GND
GND
Power source
29
ANT
External antenna output
Table 2
Pin definition Table
3. Typical application circuits
Below is the basic application circuit reference of this module, if you need more functions, please refer to the
module manual or contact our engineers to assist.
Figure 2 Basic minimum circuit (disables low-power sleep function)
The enable and disable of the module's low-power sleep function can be set by the AT command, which is
disabled by default.
If the low-power sleep function is enabled, the module is controlled by the level of the sleep control input pin,
which is used to enter or exit hibernation, and the module outputs the current sleep state by the sleep state output
pin.
