MCU controlled Bluetooth automation

Description: The microcontroller used is 0822 zilog encore! 8k series (soic,28pin) as shown on the figure. Is a programmable microcontroller, the functions used are the GPIO and the UART of the chip. GPIO is used on led indicators, and the UART is used for giving and reading AT COMMANDS to control the Bluetooth device. The whole process of the circuit, is to control the remote device using the 1st board (controller board), to switch a certain load on/off vice versa. Figure 1 explains how to use the controller and figure 2 explains how it functions according to the user. The user will enable the switches for the loads, then the mcu will give commands to the Bluetooth serial, then the remote device will receive the data, to enable the load. The controller board consists of the Bluetooth device, 0822 zilog encore, the max232 IC for programming, DB9 connector and some components, this board has a built in programmer, so it can be re-programmed any time the user wants to. D9 and D10 is used to indicate connectivity from the other Bluetooth module(the remote device), it should be in the on condition. If it is not, the reset button can be pressed to make a new connection to the remote device. The max232 IC from maxim, is connected to a switch(DPDT, to make it much more cheaper), for either programming or serial communications in the hyperterminal of the PC. D1-D4 is used to indicate the switch status. D5-D9 is optional, it can be used to indicate the status of the load in the remote device, so the programming will be that easy. The power supply of the controller board consists of 3.1265 volts(LM317) and the LM7805 ic. The circuit of the op-amp, using a simple comparator. To drive a relay, which will also drive the 12volts buzzer. buzzer The infrared switch can be used as an alarm to intruders at home. The process of the whole circuit is like a simple switch, but uses infrared, that, If the signal from the infrared transmitter is blocked, the buzzer will turn on, this will serve as a simple alarm that can have many useful applications. The whole circuit components are soldered directly, without PCB.

The described circuit utilizes the Zilog Encore! 0822 microcontroller, a 28-pin SOIC device, which serves as the central processing unit. This microcontroller is programmable and features General Purpose Input/Output (GPIO) and Universal Asynchronous Receiver-Transmitter (UART) functionalities. The GPIO pins are employed for controlling LED indicators, while the UART is responsible for transmitting and receiving AT commands to manage a Bluetooth module, facilitating wireless communication with a remote device.

The primary function of the circuit is to enable remote control of a specific load through a controller board. The user interacts with the system via switches that activate or deactivate the load, with the microcontroller processing these inputs and sending corresponding commands to the Bluetooth module. Upon receiving these commands, the remote device executes the required actions.

The controller board incorporates several critical components, including the Bluetooth module, the Zilog microcontroller, a MAX232 integrated circuit (IC) for level shifting, and a DB9 connector for serial communication. Additionally, the board features a built-in programmer, allowing for reprogramming as needed. Status indicators D9 and D10 signal the connectivity status of the Bluetooth module; these LEDs should remain illuminated to confirm a successful connection. If connectivity is lost, a reset button is provided to re-establish the link.

The MAX232 IC connects to a Double Pole Double Throw (DPDT) switch, enabling the selection between programming mode and serial communication with a PC via hyperterminal. Indicator LEDs D1 to D4 show the status of the switches, while D5 to D9 are optional indicators for the load status on the remote device, enhancing user feedback during operation.

The power supply circuit employs an LM317 voltage regulator to provide approximately 3.1265 volts, supplemented by an LM7805 IC to ensure stable 5-volt power for the microcontroller and other components. An operational amplifier configured as a comparator is utilized to drive a relay, which in turn activates a 12-volt buzzer for alerting purposes.

Additionally, an infrared switch serves as an intrusion detection mechanism. When the infrared signal is obstructed, the buzzer is triggered, functioning as an alarm system. This simple yet effective design allows for various practical applications in security and automation. The entire assembly is constructed without a printed circuit board (PCB), with components soldered directly, promoting a compact and straightforward design approach.The microcontroller used is 0822 zilog encore! 8k series (soic,28pin) as shown on the figure. Is a programmable microcontroller, the functions used are the GPIO and the UART of the chip. GPIO is used on led indicators, and the UART is used for giving and reading AT COMMANDS to control the Bluetooth device. The whole process of the circuit, is to control the remote device using the 1st board (controller board), to switch a certain load on/off vice versa.

Figure 1 explains how to use the controller and figure 2 explains how it functions according to the user. The user will enable the switches for the loads, then the mcu will give commands to the Bluetooth serial, then the remote device will receive the data, to enable the load.

The controller board consists of the Bluetooth device, 0822 zilog encore, the max232 IC for programming, DB9 connector and some components, this board has a built in programmer, so it can be re-programmed any time the user wants to. D9 and D10 is used to indicate connectivity from the other Bluetooth module(the remote device), it should be in the on condition.

If it is not, the reset button can be pressed to make a new connection to the remote device. The max232 IC from maxim, is connected to a switch(DPDT, to make it much more cheaper), for either programming or serial communications in the hyperterminal of the PC. D1-D4 is used to indicate the switch status. D5-D9 is optional, it can be used to indicate the status of the load in the remote device, so the programming will be that easy.

The power supply of the controller board consists of 3.1265 volts(LM317) and the LM7805 ic. The circuit of the op-amp, using a simple comparator. To drive a relay, which will also drive the 12volts buzzer. buzzer The infrared switch can be used as an alarm to intruders at home. The process of the whole circuit is like a simple switch, but uses infrared, that, If the signal from the infrared transmitter is blocked, the buzzer will turn on, this will serve as a simple alarm that can have many useful applications. The whole circuit components are soldered directly, without PCB.