1. Microcontroller Based Digital Code Lock
Presenters:
Feni Amrutiya IT08
Vishruti Mehta IT11

2. Why do we need Microprocessors/controllers?
The microprocessor is the core of computer systems.
Nowadays most of communication, digital entertainment, portable devices, are controlled by them.

3. Invent of microcontroller
This is an ONE chip true computer.
It is optimized for a specified application.
It consist all the features of a microprocessor also has the features to built a complete computer.

4. Microcontroller : A smaller computer On-chip RAM, ROM, I/O ports...
Example：Motorola’s 6811, Intel’s 8051, Zilog’s Z8 and PIC 16X
Microcontroller

5. Cont…
The first 8 bit microcontroller, 8048 was built by INTEL in 1976 with a view to control general task.
Many companys such as intel, phillips, Dallas and Atmel corporation built many series of microcontrollers whith change in configuration of ram,rom, I/O pins, timer, interrupt, number of timers etc.

6. The one in our topic is AT89C2051.
Which has 2Kb of ROM, 128 bytes RAM, 15 I/O pins, 2 timers, 6 interrupts and 3V Vcc supply.
EVERYTHING INBUILT.

7. Microprocessor vs. Microcontroller
CPU is stand-alone, RAM, ROM, I/O, timer are separate
designer can decide on the amount of ROM, RAM and I/O ports.
expansive
versatility
general-purpose
costly
Microcontroller
CPU, RAM, ROM, I/O and timer are all on a single chip
fix amount of on-chip ROM, RAM, I/O ports.
inexpensive
for applications in which cost, power and space are critical
single-purpose
cheap
versatility 多用途的: any number of applications for PC

8. Block Diagram of micro controller

9. Type 1: Harvard Architecture
Uses separate memories for program and data with their independent address and data buses.
Because of two different streams of data and address, there is no need to have any time division multiplexing of address and data buses.

10. Cont… Supports parallel buses for address and data.
Allows a different internal organization such that instruction can be pre-fetched and decoded while multiple data are being fetched and operated on.
Data bus may have different size than the address bus which allows the optimal bus widths of the data and address buses for fast execution of the instruction.

11. Type 2: Von Neumann Architecture
Programs and data share the same memory space.
Allows storing or modifying the programs easily.
The code storage may not be optimal and requires multiple fetches to form the instruction.
Program and data fetches are done using time division multiplexing which affect the performance.

12. 8051A development overview

13. Project Objective
Design and develop microcontroller based digital code lock.
Build a high security number lock system.
Implement and deliver the required results.
Develop the ability to use the available technology in communication, power and software.

14. Introduction of the Project
Security is a prime concern in our day-today life.
This is our Microcontroller based project used as a security barrier.
Can be utilized as door lock or other security barrier.
An access control system that allows only authorized persons to access a restricted area.

15. Digital code lock system
8 bit microcontroller AT89C2051
2Kbytes of ROM for the program memory
The password is stored in the EPROM
Using Keypad we can entered the password
If password is right then relay gets on otherwise alarm switched on.

16. Features & Benefit Features: Benefits: Security for a little price
Easy to implement
Benefits:
Peace of mind.
Convenient security monitoring system.
Can be modified as needed easily.

17. Project Design
This system uses a programmable microcontroller which is programmed for 3 different functionalities.
Unlock the door by matching the security code entered by the user.
Allows to set our own security code.
In an emergency, the system can be unlocked by pressing the emergency button from inside.

18. Project Design
The system comprises a number keypad and the keypads are connected to the 8 bit microcontroller AT89C2051(Atmel). This is one of the popular Microcontroller. It has only 20 pins and there are 15 input/output lines. The microcontroller has a program memory of 2 Kilobytes.
The circuit works with the Microcontroller 89C Other components include Capacitors, Resistors, LED, Push Buttons, and a crystal Oscillator.

19. Cont…
The basic working and operation is done through a Keypad that takes input sends it to 89C2051 where this microcontroller process the input through a Program stored into it.
The circuit responds to the input as either a correct code or a false code.
In case of a correct code a voltage output is been generated that opens the door lock or any attached security mechanism. The wrong code is not entertained and emergency signal is generated for the attention purpose.

20. Example :-Door lock NOTE: Change Password Manual Open CHECK THE
READ
KEYPAD
START
DOOR OPEN
CHECK IF WRONG
PASSWORD ENTERED
3 X
ALARM ON
CORRECT
WRONG
3 PASSWORD ATTEMPT
NOTE:
Change Password
Manual Open

21. Project Design – circuit diagram

22. project with dial up hardware diagram

23. Conclusion Accomplishment: Board design which is pact and simple.
The invasive design gives the prototype model to use easily and can be implemented to make it to work with cell phone to open the lock remotely.
Furthermore use of AT89C2051 give us flexibility to work around with other components in a cost effective way.
Ethical Consideration:
Created a device that is user friendly
Eliminate the risk of PCB board replaced visible wire usage.
Fixed connections on the board with pinheads