This can be considered as tutorial for the project "CID Calculator"

1. By P. Venkata Sai Vamsi,
3rd Year EE, B.Tech,
IIT Indore.
ELECTRONICS CLUB, IIT INDORE

2. Outline
•
•
•
•
•
•
•
Introduction
Block Diagrams
Classifications in Microcontrollers (Atmega 32A)
Integration of Keyboard with the Microcontroller
Integration of LCD Display with the Microcontroller
CID CALCULATOR
Programming

3. Introduction (Source – Wikipedia)
Microprocessor:- The microprocessor is a multipurpose
programmable device that accepts digital data as input, processes
it according to instructions stored in its memory, and provides
results as output.
8085 MICROPROCESSOR

4. Microcontroller:- is a small computer on a single integrated
circuit containing a processor core, memory, and
programmable input/output peripherals.
Example:Microcontroller based
Microwave
Peripherals:- is a device that is connected to a host computer,
but not an integral part of it. It expands the host's capabilities
but does not form part of the core computer architecture. It is
often, but not always, partially or completely dependent on the
host.

5. There are three different types of peripherals:
I. Input devices (mouse, keyboards, etc.)
II. Output devices (monitors, printers, etc.)
III. Storage devices (hard drives, flash drives, etc.)
Examples:-
4x4 Keypad
16x2 LCD Display

6. Microprocessor Block Diagram
Ex:- Keyboard
MICROPROCESSOR

7. Microcontroller Block Diagram
MICROCONTROLLER
PORTS

8. Classifications in Microcontrollers (ATMEGA 32A)
• Ports:- PORT A, PORT B, PORT C, PORT D
Each port consists of 8 pins, to transfer 8 bit data between the
Microcontroller and the Peripheral devices. These ports can acts
as both input/output ports.
• Interrupts:- INT 0, INT 1
interrupt is a signal to the processor emitted by hardware or
software indicating an event that needs immediate attention.
The processor responds by suspending its current activities,
saving its state, and executing a small program called
an interrupt handler (or interrupt service routine, ISR) to deal
with the event. This interruption is temporary, and after the
interrupt handler finishes, the processor resumes execution of
the previous thread.

9. Edge triggered interrupt:- An edge-triggered interrupt is an
interrupt signaled by a level transition on the interrupt line,
either a falling edge (high to low) or a rising edge (low to high).
***For more details in using Interrupts contact me pvsvamsi2009@gmail.com
Active Low and Active High:- If any port is activated by giving
low (0) input, then it is called as Active Low and vice versa.
Ex:- Reset is active low

10. • ATMEGA 32A Pin Configuration
Back

11. Integration of Keyboard with the Microcontroller

12. Key Board Integration (4x4 Keyboard)
Switches
Here I connected the
keyboard to PortB.
Any port will solve the
purpose.

13. Before Pressing a key

15. By following the above procedure, we can get the row no of the
key pressed.
Question:- How we will find the column no of the key pressed?

16. By following the above procedure, we can get the ‘row no’ of the
key pressed.
Question:- How we will find the ‘column no’ of the key pressed?
Answer:- By setting the value of each column to ‘1’ (one at a
time), we can observe the change in the state of the row 1 for
the corresponding change in the state of column 1 (here we
pressed the 1st key).
*****This is the end of the keyboard integration*****

17. Integration of LCD Display with the Microcontroller
Why do we prefer LCD Display to 16/17 segment ALPHA Numeric
Display?
Reasons:1. Length of the display - In 16x2 LCD Display unit, we can
display up to the 32 characters. Whereas, in 16/17 segment
ALPHA Numeric Display we require, 32 display units to
display the same.
2. Ease of use – Predefined libraries are available for the LCD
Display.

18. Integration of LCD Display with the Microcontroller
Connections with Atmega 32A

19. Procedure
Add the predefined libraries to your project folder and initialize
the LCD subsystem using a call to LCDInit(LS_BLINK|LS_ULINE).
To write any text call LCDWriteString("Welcome"); To write any
number call void LCDWriteInt(int val,unsigned int field_length);
This will print a integer contained in “val”. The field length is the
length of field in which the number is printed.
Example:- LCDWriteInt(3,4); will print as follows

20. Question:- Can any one guess what happens if we write
LCDWriteInt(123,5); ?

21. Question:- Can any one guess what happens if we write
LCDWriteInt(123,5); ?
Answer:-

22. Next function - void LCDGotoXY(uint8_t x,uint8_t y);
Here, uint8_t represents unsigned integer which is 8bit.
So, the maximum number it can store = 2^8-1 = 255.
LCDGotoXY(11,1);
This function changes the cursor position to the given X,Y
coordinates.

23. LCD Display panel, will retain the previously displayed value. It
won’t clear it.
Well, does anyone wonder how to clear the display then?
Here comes the use of another important function LCDClear();
This will clears the display and reset’s the default cursor position
to (0,0).
Next function - LCDWriteStringXY(x,y,msg);
With this function, user can display the message at his desired
coordinates.

24. For Example:LCDWriteStringXY(3,0,”hello”);
LCDWriteStringXY(8,1,”world”);
Similarly there is a function for integers.
LCDWriteIntXY(x,y,num,field_length);
*****This is the end of the LCD Display integration*****

25. FLUXUS 2014
CID CALCULATOR
FEB 7th 2014
Basic components required:1. ATMEGA 32A Microcontroller
2. Display unit ( I suggest you to use
16x2 LCD Display unit)
3. 4x4 Keyboard(No restriction with
the size)
4. Connecting Wires
5. Circuit Board
6. Battery
7. *HD74LS08 IC (AND Gate)
8. **Programmer
*Depends on whether you are going to use interrupts or not.
**We do possess one USB Programmer, which can be used for programming.
Bread boards, Soldering wire and Soldering irons are available with our electronics club.

26. How to start???
I think this is the big question in your mind!!!

27. Steps to complete the CID CALCULATOR:-
1.
2.
3.
4.
Finish off the connections part.
Start programming the microcontroller.
Implement your own ideas.
Test the functionalities of your design.
That’s it!!!

28. How to Connect??

29. How to Connect??
Connection’s part is already covered!!!

30. Programming
Software used: Atmel Studio 6.1
Size: Around 900MB
(This can be downloaded directly from the atmel website)
Language: ‘Embedded C’
There is no much difference between ‘embedded c’ and ‘c’.

31. How to connect the Programmer
ISP- In System Programming
If you remember the pin
configuration of ATMEGA 32A
MOSI - Pin 6
MISO - Pin 7
SCK - Pin 8
RESET - Pin 9
VCC - Pin 10
GND - Pin 11

32. Sample Program
Atmel Studio 6.1
To Blink an LED:#define F_CPU 8000000UL //Setting the clock frequency for
using delay
#include<avr/io.h>
#include<avr/interrupt.h> // For Interrupts
#include<util/delay.h>
// For Delay function
int main(void)
{ DDRD = 0xFF;
//setting Port D as output port
while(1)
//to run the loop continuously
{ PORTD = 0XFF;
//giving high (1) as output to the port D
_delay_ms(1000); //giving delay
PORTD = 0x00;
//giving low (0) as output to the port D
_delay_ms(1000); //giving delay
}}

33. THANK YOU
For queries, write to me @
pvsvamsi2009@gmail.com