Bluetooth 4 Relays Control Pro 1.0

This project showcases a straightforward Android Bluetooth Remote Control system designed for managing four relays utilizing the 89C2051 microcontroller and HC-05 Bluetooth module.

The circuit diagram and hex file can be accessed here.

App Instructions:

1. Ensure that your HC-05 Bluetooth Module is successfully paired with your mobile device. The default pairing passwords are "1234" or "0000"; please consult the Bluetooth module's manual for further details.
2. Pressing the ON button for Device 1 sends the command "A" to the Bluetooth Module connected to the circuit. When the microcontroller receives this command, it activates Device 1's relay.
3. Similarly, pressing the OFF button for Device 1 transmits the command "a". Upon receiving this command, the microcontroller deactivates Device 1's relay.
4. Pressing the ON button for Device 2 sends "B" to the Bluetooth Module. The microcontroller will turn on Device 2's relay in response to this command.
5. The OFF button for Device 2 sends "b", which instructs the microcontroller to turn off Device 2's relay.
6. For Device 3, pressing the ON button results in sending "C" to the Bluetooth Module, leading to activation of its relay by the microcontroller.
7. Pressing OFF for Device 3 transmits "c", prompting the microcontroller to deactivate the corresponding relay.
8. When the ON button for Device 4 is pressed, "D" is sent to the Bluetooth Module. The microcontroller then activates Device 4's relay.
9. Finally, pressing OFF for Device 4 sends "d", which causes the microcontroller to turn off Device 4's relay.