BLE4.2 bluetooth serial module 2.4G 1T1R HLK-B20 Single-Mode Test Board
HLK-B20 is an new low-consumption Bluetooth BLE 4.2 control module made by Hi-Link. This product is a Bluetooth-compliant module based on universal serial interface. It has built-in BLE 4.2 protocol stack, which can realize data conversion between user serial port and Bluetooth interface.
High-speed ARM9E core MCU
2.4G/1T1R, BLE 4.2
160k programming space, 20KB RAM
Power supply voltage 0.9-3.6v
Ultra low supply voltage, low power consumption
Built-in crystal, high stability
Small chip package 4x4
Rich peripheral interface, SPI, I2C, ADC, UART, PWM, GPIO
Widely used in the Internet of Things
High-speed 10-bit multi-channel ADC with internal filtering
Easy to connect, fast speed
The module function is mainly to realize the mutual conversion of Bluetooth data and serial data.
Figure: Serial to BLE mode
In this mode, the BLE Bluetooth device transmits the data to the HLK-B20 module via Bluetooth, and the HLK-B20 module sends the received data from the serial port. When the serial port gets data, the HLK- B20 sends the serial port data from the Bluetooth terminal to realize the conversion of serial data and Bluetooth data. When the HLK-B20 has a Bluetooth device connected, the HLK-B20 will turn off the broadcast of the Bluetooth name, and other Bluetooth devices will no longer be able to connect to the HLK- B20.
Serial port working state conversion
Figure: Serial port working state transition
The module defines the working state of the serial port as two modes: transparent transmission mode and AT command mode.
After normal power-on, the module directly enters the transparent mode. If Bluetooth is not connected, the data will not be sent out from Bluetooth. If Bluetooth is connected, the data will be sent out from Bluetooth. In any state, keeping the ES0 pin low for longer than Tes and less than Trst will immediately enter the AT command mode