The baseplate makes the module more universal, and the 6 pins are directly con nected to the serial port of the single chip microcomputer. After the pair is paired successfully, data can be transparently transmitted through the serial port.
Pin:
EN, VCC, GND, RXD, TXD, and STATE. STATE is the Bluetooth status pin, which outputs low level when not connected, and high level when connected. EN is equivalent to the KEY pin, which can clear the host pairing memory.
Voltage description:
WAVG
The input voltage is 3.2 6V, the power supply has anti-reverse connection, but the reverse connection does not work.

Status indicator:
CAT
Module onboard LED status indicator, before connecting, the host does not reco rd the slave address, on 100ms per second When the host records the slave add ress, the light is on for 900ms per second. The slave machine lights up for one second every two seconds. After the connection, the host and slave LED are always on.
Interface level:
RXD, TXD for 3.2-6V TTL level, 5V microcontroller can be directly connected.
Communication distance:
Under the open environment, the communication distance can reach 80 meters.
Communication format:
After pairing, the serial port can be used as a full-duplex serial port without an y Bluetooth protocol. However, only 8 data bits and 1 stop bit are supported. The communication format of parity check is not specified. The parity bit can be changed.

Equipment support:
WA
Support with iPhone4s and Android4.3 above mobile phone connection communication (need to download BLE serial test assistant) module can not be directly connected with PC or mobile phone bluetooth, which is also the feature of BLE bluetooth module.
Default value:
Baud rate 9600, Bluetooth NAME HC-08, LED status light on.