There may be chances that they remember to take the pills at regular times but forget the pill which has to be taken at that particular time. This is a big problem and it is also difficult to doctors to monitor patients always. And also, mostly in the hospitals, it is not an easy and available service to employ a nurse to a single patient exclusively. To avoid these problems, we have implemented this project which can remind the patient about the intake of medicines at regular time intervals and also sends the information to the doctor about the patient if the temperature or the heartbeat exceeds the normal set point.
This project is designed mainly for patients and old aged people. The project can be seen more clearly in two different modules- medicine intake informer and voice guider. The medicine intake informer consists of RTC (DS1307), buzzer and 16X2 LCD display. The system continuously reads the time from RTC and compares this time with the already time and if these two times match, the system immediately alerts the buzzer for a predefined time and displays the name of the medicine, to be taken by the patient, on the LCD. The voice guider consists of voice playback APR9600, speaker and IR receiver.
The user will be provided with an ordinary IR TV remote. If the user is unable to do the things by himself or requires any immediate help, he can press any of the predefined keys in the remote. The IR receiver receives the IR signals from the transmitter and passes this data to the voice playback. The message corresponding to the pressed number will be announced and can be heard through the speaker. If the patient or the old person is unable to ask the things like water, fruits etc directly, he can press the defined button in the remote.
Then the controller receives this input from IR receiver and the message related to the number pressed will be heard in the form of voice from the speaker. Thus, the patient can get the required help immediately. 1. 1. Basics of Embedded Systems An embedded system is a computer system designed to perform one or a few dedicated functions often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. Embedded systems control many devices in common use today.
Embedded systems are controlled by one or more main processing cores that are typically either microcontrollers or digital signal processors. The key characteristic, however, is being dedicated to handle a particular task, which may require very powerful processors. Physically embedded systems range from portable devices such as digital watches and MP3 players, to large stationary installations like traffic lights, factory controllers, or the systems controlling nuclear power plants. Complexity varies from low, with a single microcontroller chip, to very high with multiple units, peripherals and networks.
Fig-1: Embedded Systems Processors: Processors are the ones which performs some specific task or operation. These are divided in to several types like: 1. Digital Signal Processors. 2. Application Specific Integrated Circuits. 3. Micro Processors. 4. Micro Controllers. Digital Signal Processors: This is a one which performs scientific and mathematical Calculations. The output of this type of processors will be in floating point values. Hence, we can get accurate values as outputs.
Best example of a Digital Signal Processors will be Weather Forecasting. Applications specific Integrated Circuits: As the name itself specifies, this is integrated circuit designed for a specific application. IC designed for one specific application cannot be used in other applications. Best Example for ASIC will be Cell phone card. Microprocessors: These are the ones which perform arithmetic and logical operations. Arithmetic and logical unit performs arithmetical and logical calculations. Control unit controls all the peripheral devices connected to the microprocessors.
Memory is a one which is used to store some data or information. Best Example for a microprocessor will be our Personal Computer. MicroControllers: These are the ones which are similar to that of a microprocessor which performs arithmetic and logical calculations. These have additional advantage to that it is having additional inbuilt features like: Fig-3: Block Diagram of Micro Controller 1. Electrically Erasable Programmable Read Only Memory (EEPROM) 2.
Universal Synchronous Asynchronous Receiver and Transmitter (USART). 3. Analog to Digital Converter (ADC). 4. Digital to Analog Converter (DAC). 5. Oscillators. 6. Timers. 7. Many others. The output of a microcontroller is always in integer format only. It cannot provide accurate values or floating point values. Coming to the software point of View, we have many software languages. Out of all, we are using Assembly Level Language to load the program in to the controller. We are using Atmel manufactured microcontrollers. Atmel Company manufactures different series of microcontrollers like AT89C, AT90S, AT Mega, AT CAN.
All the electronic components starting from diode only works with a DC supply ranging from 5V to 12V. We are utilizing for the same, the cheapest and commonly available energy source of 230V-50Hz and stepping down, rectifying, filtering and regulating the voltage. Fig-4: Block Diagram of Power Supply 2. 3. 1. Transformer: A bridge rectifier coupled with a step down transformer is used for our design. The voltage rating of transformer used is 0-12V and the current rating is 500mA. When AC voltage of 230V is applied across the primary winding an output AC voltage of 12V is obtained.
One alteration of input causes the top of transformer to be positive and the bottom negative. The next alteration will temporarily cause the reverse. Fig-5: Transformer Block Diagram 2. 3. 2. Rectifier: In the power supply unit, rectification is normally achieved using a solid state diode. Diode has the property that will let the electron flow easily at one direction at proper biasing condition. Bridge rectifiers of 4 diodes are used to achieve Bridge wave rectification. Two diodes will conduct during the negative cycle and the other two will conduct during the positive half cycle.
Fig-6: Transformer along with Rectifier 2. 3. 3. Filtering unit: Filter circuit which is usually a capacitor acts as a surge arrester always follows the rectifier unit. This capacitor is also called as a decoupling capacitor or a bypass capacitor, is used not only to short the ripple with frequency to ground but also leave the frequency of the DC to appear at the output. 2. 3. 4. Voltage Regulator: The voltage regulator plays an important role in any power supply unit. The primary purpose of a regulator is to aid the rectifier and filter circuit in providing a constant DC voltage to the device.
Power supplies without regulators have an inherent problem of changing DC voltage values due to variations in the load or due Fig-8: Transformer along with Rectifier, Filter and Regulator to fluctuations in the AC line voltage. With a regulator connected to DC output, the voltage can be maintained within a close tolerant region of the desired output. IC 7805 and 7812 regulators are used in this project for providing a DC voltage of +5V and +12V respectively. 2. 4 AT 89S52 MICROCONTROLLER 2. 4. 1. Description The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory.