Abstract:
Security is prime concern in our day-to-day life. Every one wants to be as much as secure as to be possible. An access control systems forms a vital link in a security chain. The microcontroller based lift operating system presented here is an access control system that allows only authorized persons to access the lift. This system also gives the voice messages about floor number and door opening and closing status and also alert about fire accidents.
The system comprises a small electronic unit with a numeric keypad, which is fixed outside the lift to control a solenoid-operated lock with the help of a DC motor.
When an authorized person enters predetermined user ID and password through the keypad, the DC motor is operated for a limited time to unlatch the solenoid-operated lock so the lift door can be opened. At the end of preset delay, the DC motor is operated in reverse direction and the door gets locked again.
To play the voice messages we do not need any separate voice module because we can play that voice from ARM7 LPC2148 micro controller directly by saving pre recorded voice message in micro controller’s memory in the form of binary.
16X2 LCD is used to display the status messages and request switches are used in each floor.
BLOCK DIAGRAM:
Software Tools:
- KEIL IDE for developing micro controller code
- ORCAD for designing schematics
- FLASH MAGIC for dumping the hex file into controller
Hardware Tools:
- ARM7 LPC2148Micro controller.
- Audio amplifier.
- Speaker.
- Keypad.
- 16X2 LCD
- switches
- Regulated +3.3v and +5v Power supply.
Advantages:
- Safe and secured
- User friendly
- Visually impaired persons can also operate
Applications:
- Access control system
- Fire alert systems