HC‐05 module is easy to use Bluetooth SPP (Serial Port Protocol) module, designed for transparent wireless serial connection setup.
The HC-05 is a class 2 Bluetooth module designed for transparent wireless serial communication. It is pre-configured as a slave Bluetooth device. Once it is paired to a master Bluetooth device such as PC, smartphone and tablet, its operation becomes transparent to the user. No user code specific to the Bluetooth module is needed at all in the user-microcontroller program.
The HC-05 supports two work modes: Command and Data mode. The work mode of the HC-05 can be switched by the onboard push button. The HC-05 is put in Command mode if the push button is activated. In Command mode, user can change the system parameters (e.g. pin code, baud rate, etc) using host controller itself of a PC running terminal software using a serial to TTL converter. Any changes made to system parameters will be retained even after power is removed. Power cycle the HC-05 will set it back to Data Mode. Transparent UART data transfer with a connected remote device occurs only while in Data Mode.
The HC-05 can be reconfigured by the user to work as a master Bluetooth device using a set of AT commands. Once configured as master, it can automatically pair with a HC-05 in its default slave configuration or a HC-06 module, allowing a point to point serial communications.
Slave default Baud rate: 9600, Data bits:8, Stop bit:1,Parity:No parity. PIO9 and PIO8 can be connected to red and blue led separately. When master and slave are paired, red and blue led blinks 1time/2s in interval, while disconnected only blue led blinks 2times/s.
Auto‐connect to the last device on power as default.
Permit pairing device to connect as default.
Auto‐pairing PINCODE: "1234" as default.
Auto‐reconnect in 30 min when disconnected as a result of beyond the range of connection.
VCC: positive power supply.
GND: negative power supply.
RXD: received end,Bluetooth module received data from other equipment.
TXD: sending end,Bluetooth module sending data to other equipment.
EN:used end,need to enter mode AT with voltage 3.3V.
Package including:1 x HC-05 bluetooth serial wireless module