Connect this circuit to any of your home appliances (lamp, fan, radio, etc) to make the appliance turn on/off from Android mobile via Bluetooth. The system involves Microcontroller AT89c51 to get data from Bluetooth device and activate corresponding load via relay.
Our system is provided with eight channels through which for devices can be controlled. This can be extended to any number of devices.
Microcontroller used is AT89S52 form 8051 family to work in a serial communication UART mode the communication is configured on 9600bps to communicate it with the Bluetooth module.
The Bluetooth module used is a HC-05 in smd package which works on a 3.3v and have a serial communication with any device connected to it the communication speed can be configured on various speed via AT Command.
The BT module is a SPP supported profile so it can be connected easily to any module or phone. In this profile the data can be sent and receive to module. The BT module is connected to the RX pin of microcontroller.