2. SESSION’S AGENDA
 Introduction To 8051 Microcontroller
 Characteristics of 8051 Microcontroller
 Pin Diagram Of AT89C51
 Programming Languages
• Assembly Language
• High Level Language (Hardware C )
 Software Used
 Led, 7 Segment, LCD And Its Interfacing
 Project Undergone
• Interfacing of Digital Clock With Visitor Counter

3.  The Intel 8051 micro controller is the "grandfather" of all
modern micro controllers. Over 10 manufacturers (including
Intel) now make over 100 different varieties of 8051 micro
controllers.
 It was developed in 1971.
 The most commonly used 8051 ICs are AT89C51,AT89S51.
 8051 microcontroller enters the data in HEXADECIMAL.
 Maximum Storage of 8 bit microcontroller is 255.
INTRODUCTION TO 8051
MICROCONTROLLER(MCU)

4. Characteristics of Microcontroller
(MCU)
 RAM 128 Bytes
 ROM 4 KB
 Extended Memory up to 64 KB
 Architecture Von Neumann
 Technology CISC
 Power Required +5 V (DC)
 Bovd rate 9600
 Packaging DLP
 Timers TMOD,TCON
 GPR 32 bits
 Frequency to run
a program 921.6 KHz
 Time to run
a program 1.085 μsec

5. Pin Diagram of
AT89C51
 It is 40 pin IC.
 It has 4 Port(P0,P1,P2,P3).
 It has 8 special pins and 32 general
pins .
 8 special pins are :
 9th pin(Reset) has the highest
authority.
 18,19 pins are for providing pulse by
crystal oscillator.
 20 pin is generally grounded.
 29 pin-PSEN(Program Store Enable)
 30 pin-ALE(Address Latch Enable)
 31 pin-EA (Enable/External access)
 40 pin is given VCC i.e. power

6. ASSEMBLY LANGUAGE
 It is a Case Insensitive Language.
 Basic elements are Label, Comments, Operands,
Directives and Commands.
 A Label is a textual designation (generally an easy-to-
read word) for a line in a program, or section of a
program .
 Comment is a series of words that a programmer
writes to make the program more clear and legible.
 An operand is a value on which the instruction is to
be performed. The operand may be a processor
register, a memory address, a literal constant, or a
label.
 Directive is similar to an instruction, but unlike an
instruction it is independent on the microcontroller
model, they are usually given purposeful meanings via
variables or registers.

7. ASSEMBLY LANGUAGE
 Commonly used ,Commands are as following :
 MOV
Syntax : MOV desination,source
Example: MOV R1,#20h
h represents no is in hexadecimal
R1 is a destination register
# is pond sign
Note: When there is an alphabet at MSB then 0 is
always used before it i.e.
MOV R1,#0a4h
MCU accepts 8 bit data hence to represents 0-9 no
we use 0 before it i.e.
MOV R1,#04h

8. ASSEMBLY LANGUAGE
 ADD
Syntax: ADD desination,source
ADD command is always used in
accumulator.
 JZ
Syntax: JZ A, label
Jump if zero i.e. if A=0 then Jump to label
Example: org 00h
MOV A ,#0
JZ A,SS
MOV R1,#6
SS:MOV R2,#23
END
MOV R1,#6 will not be performed as it will jump to SS

9. ASSEMBLY LANGUAGE
 JNZ
Syntax :JNZ A, label
Jump if not zero i.e. if A≠0 then Jump to label
Example: org 00h
MOV A ,#10
JNZ A,SS
MOV R1,#6
SS:MOV R2,#23
END
MOV R1,#6 will not be performed as it will jump to SS
 DJNZ
Same as JNZ only the value of the Accumulator is
decremented
 INC/DEC
Value of register is incremented and decremented
 CPL
Compliment of the accumulators value

10. HIGH LEVEL LANGUAGES
o Embedded C is a high level language that is
commonly used
o Developed by Dennis Ritchie & Bell Labs
o C is a Case Sensitive Languages
o C use header file <reg51.h>
o SPECIAL FUNCTION REGISTER
 Sbit is used to set a bit high
 It is written before main function and after
header file

11. Software Required
 Keil software used to write program in either of the
language c or assembly
 Editor window Human
Assembler
Linker Machine
OH Converter
UC
 Proteus is used to design the software circuitry
 It is used to see the code interaction with simulated
Hardware in Real time.
 Avaible for PIC,8051,MSP430,AVR,HC11,ARM7/LPC2000
and basic Stamp Processors

12. Light Emitting Diode And Its
Interfacing
 Color: LEDs can emit light of an intended color
without using any color filters as traditional lighting
methods need. This is more efficient and can lower
initial costs.
 Size: LEDs can be very small (smaller than 2 mm).
 On/Off time: LEDs light up very quickly
 Applications :
• Indicators and signs
• Data communication and other signaling
• Sustainable lighting

13. Design
XTAL2
18
XTAL1
19
ALE
30
EA
31
PSEN
29
RST
9
P0.0/AD0
39
P0.1/AD1
38
P0.2/AD2
37
P0.3/AD3
36
P0.4/AD4
35
P0.5/AD5
34
P0.6/AD6
33
P0.7/AD7
32
P1.0
1
P1.1
2
P1.2
3
P1.3
4
P1.4
5
P1.5
6
P1.6
7
P1.7
8
P3.0/RXD
10
P3.1/TXD
11
P3.2/INT0
12
P3.3/INT1
13
P3.4/T0
14
P3.7/RD
17
P3.6/WR
16
P3.5/T1
15
P2.7/A15
28
P2.0/A8
21
P2.1/A9
22
P2.2/A10
23
P2.3/A11
24
P2.4/A12
25
P2.5/A13
26
P2.6/A14
27
U1
AT89C51
D1
LED-BLUE
D2
LED-BLUE
D3
LED-BLUE
D4
LED-BLUE
D5
LED-BLUE
D6
LED-BLUE
D7
LED-BLUE
D8
LED-BLUE

14. 7 Segment Display And Its
Interfacing
* It is generally of 2 types :
Common Cathode
 It’s 3 and 8 pins are
grounded for its
working
 More Brighter
 More Logical
Common Anode
 It’s 3 and 8 pins are
given Vcc for its
working
 Less Brighter
 Less Logical

15. Design

16. LCD And Its Interfacing
 Liquid Crystal Display
 It is manufactured by Optrax.
 Available LCD 2x16,2x20,2x40..
 2x16 LCD has 16 pins that are
 1-Ground
 2-Vcc(+5V)Dc
 3-Contrast Control
 4-Register Select
 5-Read/Write
 6-Enable
 7-14 –Data lines
 15- Positive Terminal
 16-Negative Terminal

17. Design
XTAL2
18
XTAL1
19
ALE
30
EA
31
PSEN
29
RST
9
P0.0/AD0
39
P0.1/AD1
38
P0.2/AD2
37
P0.3/AD3
36
P0.4/AD4
35
P0.5/AD5
34
P0.6/AD6
33
P0.7/AD7
32
P1.0
1
P1.1
2
P1.2
3
P1.3
4
P1.4
5
P1.5
6
P1.6
7
P1.7
8
P3.0/RXD
10
P3.1/TXD
11
P3.2/INT0
12
P3.3/INT1
13
P3.4/T0
14
P3.7/RD
17
P3.6/WR
16
P3.5/T1
15
P2.7/A15
28
P2.0/A8
21
P2.1/A9
22
P2.2/A10
23
P2.3/A11
24
P2.4/A12
25
P2.5/A13
26
P2.6/A14
27
U1
AT89S51
D7
14
D6
13
D5
12
D4
11
D3
10
D2
9
D1
8
D0
7
E
6
RW
5
RS
4
VSS
1
VDD
2
VEE
3
LCD1
LM016L

18. Interfacing of Digital Clock With
Visitor Counter
 Digital Clock
 Visitor counter

19. Interfacing of Digital Clock With
Visitor Counter
 Main components of project

20. Interfacing of Digital Clock With
Visitor Counter
XTAL2
18
XTAL1
19
ALE
30
EA
31
PSEN
29
RST
9
P0.0/AD0
39
P0.1/AD1
38
P0.2/AD2
37
P0.3/AD3
36
P0.4/AD4
35
P0.5/AD5
34
P0.6/AD6
33
P0.7/AD7
32
P1.0
1
P1.1
2
P1.2
3
P1.3
4
P1.4
5
P1.5
6
P1.6
7
P1.7
8
P3.0/RXD
10
P3.1/TXD
11
P3.2/INT0
12
P3.3/INT1
13
P3.4/T0
14
P3.7/RD
17
P3.6/WR
16
P3.5/T1
15
P2.7/A15
28
P2.0/A8
21
P2.1/A9
22
P2.2/A10
23
P2.3/A11
24
P2.4/A12
25
P2.5/A13
26
P2.6/A14
27
U1
AT89S51
D7
14
D6
13
D5
12
D4
11
D3
10
D2
9
D1
8
D0
7
E
6
RW
5
RS
4
VSS
1
VDD
2
VEE
3
LCD1
LM016L

21. THANK YOU