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Shenzhen Hi-Link Electronic Co., Ltd.
Manual
HLK-B20
14
P33
I/O P33
GPIO
15
GND
P
GND
GND
16
P02
I/O P02,SCL
GPIO,I2C
17
P03
I/O P03,SDA
GPIO,I2C
18
P04
I/O P04,SPI_CLK
GPIO,SPI
19
P05
I/O P05,SPI_MOSI
GPIO,SPI
20
P06
I/O P06,SPI_MISO
GPIO,SPI
21
P01
I/O Uart1_rxd
Uart1, Transparent transmission serial
port
22
P00
I/O Uart1_txd
Uart1, Transparent transmission serial
port
3. Test board description
The test board is mainly used to test the data transmission function of the HLK-B20's Bluetooth and
serial ports.
Figure 3
HLK-B20 module test board
3.1. Restore factory settings
To ensure that all configuration procedures are correct, first reset the module to factory settings.
Modules that are already in factory mode can skip this step. Provide 5V (1000mA) power supply to
power on the module, wait for about 1 second, let the module start up. After the startup is completed,
pull down the ES0 (PIN5) pin for more than 6S. When the LED corresponding to the STA is always
on, it means that the module is restored the factory settings successfully, then release the ES0 pin,
the system will automatically restart. The system is already in factory mode after rebooting.
RST
HLK-B20
USB to serial
port
ES0
