-
8/8/2019 8051 Tutorials 2
1/94
Chapter1: Microcontrollers
1.1 What is a microcontroller1.2 How does a microcontroller
work
1.3 ROM
1.4 RAM
1.5 EEPROM
1.6 SFR Registers
1.7 Program Counter
1.8 Control logic
1.9 A/D Converter
1.10 I/O Ports
1.11 Oscillator
1.12 Timers
1.13 Watchdog Timer
1.14 Power Supply Ciruit
Chapter 2: 8051 microcontroller
2.1 Introduction
2.2 Input Output ports
2.3 Extra memory
2.4 89s52
Chapter 3: Introduction Assembler, Opcodes and addressing
3.1 Assembly Language Programming
3.2 Opcodes
3.3 Addressing
-
8/8/2019 8051 Tutorials 2
2/94
Chapter 4: UMPS
4.1 Introduction
4.2 Your first program in simulation
4.3 Test your program in hardware
Introduction - It is all Faraday's fault
!
" # $
% &
' "
" (
&
)$#
*
+
,
-
(
#
&
!
-
8/8/2019 8051 Tutorials 2
3/94
' #
.
./+-01-1%01220
What are microcontrollers and what are they for?
'
3
4 , 5 6,61
7 8 /
5
$
# "
'
9 :
61 2-,
5
& ; ;'-9:
9:
/
How does microcontroller work
-
8/8/2019 8051 Tutorials 2
4/94
'
3
4 ;* $;"
7 $ ; " /0
;
-
8/8/2019 8051 Tutorials 2
5/94
8 " $
-
8/8/2019 8051 Tutorials 2
6/94
01++-)
90+:901+:
SFR Registers
/ 0 0+
+-)
$' " /0 61
9
:
Program Counter
$$3
, $ !
@!
)!-
A3A3A3
In case you forgot...
9
:$3
3BB
#
#"9
:
Control Logic
==
+-)
'
C "
C -
+-)
-
8/8/2019 8051 Tutorials 2
7/94
C /0 2) 9:
1 /0
/ 0
59"":
In case you forgot...
D!
2)
9:9:
4
-
8/8/2019 8051 Tutorials 2
8/94
&+-)
I/O Ports
+-) 9 :
&61.=
5
Oscillator
/
+-) -
;";"#
" ; 9 0- : %
$
9$
+-): 4B+@" ;"#
$
-
8/8/2019 8051 Tutorials 2
9/94
Watchdog Timer
+-)0-&+-)
$9!:
&
$
$ &
9 :
- #
+-)
In case you forgot...
>
$
$+-)
;
-9:$
0+-
#$
-
8/8/2019 8051 Tutorials 2
10/94
Power Supply Circuit
+-)'
C
/
+-)
# +-)
Reset pin frequently marked as MCLR (Master Clear Reset) is used
for "external" reset of microcontroller by
bringing the logical zero or one (depending on the MCU). If not
preinstalled, a simple external brown outreset circuitcan be
connected to this pin.
!"#$%
+-);#;6,DB
-
8/8/2019 8051 Tutorials 2
11/94
801+ 34D0+9/0:
87461$
1DB3493B33:
4
F' 0 /> +-) ="
!
+-),5
# ##
9:
"
-
8/8/2019 8051 Tutorials 2
12/94
3B#3H'7>3@7'
3B'0I,#
33'I,#
34'%B#B 37'%3#3 38'B#B 3 J" ; -
9:7B
;"
98H :
%+-);B@"
-
8/8/2019 8051 Tutorials 2
13/94
7B'2>=$+-) 9 B C H: B 2
$9H8@-7H7H8@-7HA
-
8/8/2019 8051 Tutorials 2
14/94
61B@324
&$9DC3
-
8/8/2019 8051 Tutorials 2
15/94
8 D 0B # 0H
/ 9 4B C 4: # 9B H:/3?
34D9=B4BB
H4H:
4CH9DB :
*+,
5#0+DB
-
8/8/2019 8051 Tutorials 2
16/94
'/0;>$0++$
#90+01+:$?8M=&614755
!+-)DB
-
8/8/2019 8051 Tutorials 2
17/94
Introduction
4B +-) DB
-
8/8/2019 8051 Tutorials 2
18/94
MCU AT89S8252 ID Card
+DB
-
8/8/2019 8051 Tutorials 2
19/94
-
8/8/2019 8051 Tutorials 2
20/94
;;;36?;
$
9B#H:
+-)
PSEN
/$901+:
EA/VPP
& +-) $
9 :
9E--: ,
A34E
XTAL 1
"+-)
$
XTAL 2
$
SFR Registers (Special Function Registers)
+-)DF/D4
-
8/8/2019 8051 Tutorials 2
21/94
=
0
9 2): &
,
;+-)
"R" registers (R0 - R7)
/00
8 0+
/&
0
14/
$&9$
:
B register
=19:
P0, P1, P2, P3 - I/O Ports
$8974
61:
9B
-
8/8/2019 8051 Tutorials 2
22/94
//
& / 3>
/ 3 9 :
H 0+ /
//
Program Status Word (PSW)
/&/0
2)
)! #93:59B:
##+-)5 '5- #$4
-
8/8/2019 8051 Tutorials 2
23/94
,',@9,@:,29,
2:,53?$/
3?#
Counters and Timers
+-) ;"
;9
:
>
+-)
/34$
;" 34 +@" 6
9:
DF/D4
-
8/8/2019 8051 Tutorials 2
24/94
$ B G B " B 3BBB9: @B 9 : 7 2B 9 :
474/
3?#'
TH0 * 256 + TL0 = T
1$'
3 * 256 + 232 = 1000
3?#$?
-
8/8/2019 8051 Tutorials 2
25/94
B#H'
1 ) $
H K3 3%3977:
B%3977:
3
? -63 3397
-
8/8/2019 8051 Tutorials 2
26/94
; ! +-) &
@B
"9B#4
-
8/8/2019 8051 Tutorials 2
27/94
: ) 4BB B + 4 +-)
%2BD#@B
4BB$&2B
@B
-
8/8/2019 8051 Tutorials 2
28/94
-
8/8/2019 8051 Tutorials 2
29/94
TH0=15, TL0=255.
/
'
TH0=14, TL0=255.
94
#1&B-1%
/
BB
-
8/8/2019 8051 Tutorials 2
30/94
90BG3:
%B
$
-
8/8/2019 8051 Tutorials 2
31/94
Timer T1
B+1,
-1%8
Timer T2
3?#6+-))B3
8 @4 24 3?#
1 0-4@ 0-42
-
8/8/2019 8051 Tutorials 2
32/94
+"
4
B3$
T2CON (Timer/Counter 2 Control Register)
04-1% 4 $
'
4 93?#:
$
0-2M-2M
4
I4 4I
,-%4-1%
I4
0-2M ##04
!#03
-2M ##4
!#3
I%4 ##4I
-
8/8/2019 8051 Tutorials 2
33/94
!#4I
04 ##/4
!#/4
-64 ##3?#94@42:-64
!#3?#94@42:
-6024 ##9I%G3:4I
!#)4I
Modes of Timer T2
Capturemode
-6024 4-1% 4 # !9
4@ 42: 9
0-4@0-42:
3 3?#9@4A24:1,4 / 04 -1% >
39?
-
8/8/2019 8051 Tutorials 2
34/94
##/$
41
3B9
:
@424
0-4@0-42
I4
-64
!#-934
;":
##-4
Auto Reload Mode
40-6024
,-%
4+1,'
41#
-%#
)! 90-4@0-42:
9@424:/0
'
4-1%I%4
!#)44-1%
0-4@0-42
-
8/8/2019 8051 Tutorials 2
35/94
##/$
41
3B9
:
0-4@0-42
@424
I4
-64
!#-934
;":
##-4
4 4+1, 5 ,-% G B 1 9 :
,4I'
4I G B' 4
4IG3'4
$
I4
44@42
'?
-
8/8/2019 8051 Tutorials 2
36/94
Quartz oscillator frequency
Baud Rate =
32 * (65536 - (RCAP2H, RCAP2L))
'
3 ;9434:
4 147 &I%44I
4I$
8 8&904GB:@4241
Timer T2 as independent clock generator
$ 3B 9 4 :
#
; ) 3?+@" ;" ;
?3@"8+@"##
-
8/8/2019 8051 Tutorials 2
37/94
-
=/0/-1%9
!:'"
"
SCON (Serial Port Control Register)
1 )
/+B F +
/+3 F +
/+4 F, +-)5
0+ F- &
=D F= F47
0=D F F47
FF =
0 FD =
/+B /+3
'
! #
B B B D#/ J";634
B 3 3 D#)0 ,34
3 B 4 F#)0 J";674
-
8/8/2019 8051 Tutorials 2
38/94
3 3 7 F#)0 ,34
1B4$!379
:347
/+1,-1%9:
Mode 0
+ B 61
$ ;
61
$7461
Mode 1
0/#474D#/;
I,0I,'9B:
D 92/= : 9 3: /
&
0=D /-1%
0/#474 #
Modes 2 and 3
; 9+ 4:
0/#474 9+ 7: = F#
'9B:D92/=:F
=D 0=D
93:
1/-1%'
)
/+4 $
1
0% %
=D $FF#947:
-
8/8/2019 8051 Tutorials 2
39/94
0=D /=D&F#
0 /
Setting the Baud Rate
1)0=0
= 0 B 4 ; ;" -
;
$ 9 33B
-
8/8/2019 8051 Tutorials 2
40/94
B B 0 ; 3
B 3 034
3 B 043
3 3 0 ; 4
Sending and Receiving Data via UART
1)0
/=)
+-)
;/-1%/
#09/-1%:
!/=)
Watchdog Timer (WDT)
&0-
#,
$ / &,% &+-1% &
&,0/9&0
&+-1%:51&
&
/&+-1%'
PS2, PS1, PS0
7#&
&,0/+-)
-
8/8/2019 8051 Tutorials 2
41/94
)- )# )! %3,
B B B 3?
B B 3 74
B 3 B ?8
B 3 3 34D
3 B B 4
-
8/8/2019 8051 Tutorials 2
42/94
SPI (Serial Peripheral Interface) System
/ 9 % :
- "
"
# # /
'/-0 9-0://0 9/0:
/,09,0:
SPCR (SPI Control Register)
/0//-0'
)
/ &/
/ &/
,10, ##&2
!#&+
+/0 ##/
!#/
-
8/8/2019 8051 Tutorials 2
43/94
-12 ##,/-M
!#,/-M+
-@ -12-@
/03
/0B
-;
9:
)# )! /0
B B 68
B 3 63?
3 B 6?8
3 3 634D
SPSR (SPI Status Register)
/0/'
)
/ )/
/
&-12 /,0/
SPDR (SPI Data Register)
/ 1 /,0 9
+:-)
+1/)/
//
-
8/8/2019 8051 Tutorials 2
44/94
Interrupts
DF/D4
-
8/8/2019 8051 Tutorials 2
45/94
1
'
3 0;!
4 3-7 4-
IP (Interrupt Priority)
/0 $
9/ ' 3
:'
)
4 4
/ /
3 3
I3 $%3
B B
IB $%B
;$
;
How does interrupt execute?
);'
-
8/8/2019 8051 Tutorials 2
46/94
3 -$4 $$
;
7 , ; ?9:
5+
B 7
B =
3 37
3 3=
0/ 47
4I4 4=
8
-
8/8/2019 8051 Tutorials 2
47/94
-8
,
DB
-
8/8/2019 8051 Tutorials 2
48/94
2. #-'S787S)+/S$&
$
3. -)-
@I3?9$:
4. -)0
$0K
5. -)01+8M01+DB
-
8/8/2019 8051 Tutorials 2
49/94
-
8/8/2019 8051 Tutorials 2
50/94
6. 0)+/
9:
-
8/8/2019 8051 Tutorials 2
51/94
-
8/8/2019 8051 Tutorials 2
52/94
7. 0+$/-34D0+DB
-
8/8/2019 8051 Tutorials 2
53/94
)+/92:
9-:$-)
-9-:
-)9-):
)+/,E2
&55'
DB739DB
-
8/8/2019 8051 Tutorials 2
54/94
0-),9DB732+787E+,:
0-) $7%!
!(-)6
E=9
2+#787:
)+/
25'
);
/U1'
/+!
;
K6@'
$9:&
@2
0'/
9-Q BBBB:
/9:'
' &$9D:
'9H: $'$9#D:
='
6-)$
-'
-9/+I:
/-9-:'
)-9-:'
/- /- /-#
-
8/8/2019 8051 Tutorials 2
55/94
060'
0-)0&'
- , $9-Q
-Q -)V0:
%1
&;
%-
2)'-)9@$:9:9:
9:
2!#=%6%
E
)-)0+01+/05
-#O2-)
-
8/8/2019 8051 Tutorials 2
56/94
-
8/8/2019 8051 Tutorials 2
57/94
-
8/8/2019 8051 Tutorials 2
58/94
-)&
DB739DB
-
8/8/2019 8051 Tutorials 2
59/94
@
)-),
*
&55#*!
DBB$?BB
)=9
3:0)+/,
4:-91#X+#X:
3) )Q Y2!Z?@='12,3,11&9%!:
4) )+/E=9E=:-)--)0&
5) -0/
-
8/8/2019 8051 Tutorials 2
60/94
-
8/8/2019 8051 Tutorials 2
61/94
-
8/8/2019 8051 Tutorials 2
62/94
-
8/8/2019 8051 Tutorials 2
63/94
-
8/8/2019 8051 Tutorials 2
64/94
-
8/8/2019 8051 Tutorials 2
65/94
-
8/8/2019 8051 Tutorials 2
66/94
-
8/8/2019 8051 Tutorials 2
67/94
-
8/8/2019 8051 Tutorials 2
68/94
-
8/8/2019 8051 Tutorials 2
69/94
?: -K1-)$E=
'
06(6K9:; -,D2,
=3,/H# =4H# /&1%!2,
/&41%H#
7) @2$8) )#%'
-
8/8/2019 8051 Tutorials 2
70/94
)/#9D:-222,V,
)/#9H:22 )/#92#D:$1ME=!5
,2,
2/)/
3:--)-#O2-)'7#@@&
%14:2E=
'
Q 2
)@'6V7876
?@?@
7:E-)E!Q -)-
8:1-)-%19
$%0:
*$)-@8
4'5)#6)!
A)'')
%$ $9/48:
[92':
#(Q -2>
-
8/8/2019 8051 Tutorials 2
71/94
/)-@8CD7
-
8/8/2019 8051 Tutorials 2
72/94
-
8/8/2019 8051 Tutorials 2
73/94
2) -3) 1-1M
-
8/8/2019 8051 Tutorials 2
74/94
-
8/8/2019 8051 Tutorials 2
75/94
4) 5) 0$,#16) -*+$7) 0,1*
%1'
2=2'%/0)-1%/>'
-
8/8/2019 8051 Tutorials 2
76/94
-
8/8/2019 8051 Tutorials 2
77/94
-
-
8/8/2019 8051 Tutorials 2
78/94
dec r1mov @r1,10hmov @r1,#0aahmov dptr,#99hmovx @dptr,amov
a,#55h
movx @r1,amovx a,@dptrmovx @r1,ainc dptrinc r1movc a,@a +
dptrmovc a,@a + pcmov sp,#40hacall testsaddadd a,10hadd a,@r0add
a,#61hadd a,r1
addc a,10haddc a,@r0addc a,r1addc a,#45hajmp saddnop
sadd:anl a,10hinc aanl a,@r1anl a,#0aahanl a,r1anl 10h,a
anl 10h,#55hclr ccpl cclr 00hcpl 00hanl c,00hanl c,/00hcjne
a,10h,here
there:sjmp compare
here:jb 00h,there
compare:cjne a,#42h,whereevery:
jbc 00h,nextwhere:
jc everynext:
cjne @r0,#11h,againdone:
clr c
-
8/8/2019 8051 Tutorials 2
79/94
jnc leaveagain:
cjne r0,#68h,doneleave:
jnz gonop
go:cpl acpl 11hmov r6,axrl a,r6mov a,#99hadd a,#99hda adec adec
15hdec @r0mov b,#11hdiv ab
djnz 11h,lessmore:
clr ajz some
less:djnz r1,more
some:inc 12hinc @r0lcall laddljmp long
back:mov 12h,c
mov c,13hnopmul aborl a,15horl a,@r0orl a,#97horl a,r1orl
20h,aorl 20h,#0fehorl c,/20horl c,30hpush 10h
pop 3chrl arlc arr arrc asetb 15hsetb csubb a,11hsubb a,@r0subb
a,#22h
-
8/8/2019 8051 Tutorials 2
80/94
swap axch a,17hxch a,@r0xch a,r6xchd a,@r1xrl a,15h
xrl a,@r1xrl a,#0ffhxrl a,r6xrl 15h,axrl 16h,#77hmov
ie,#0ffhljmp over
testsadd: retladd: retlong: ljmp backend
Exercise 2:
Write a program to complement the given program
Ans:;program to find the 2's complement fo 8 bit
org 00hmov 20h,#20h ;i/p numbermov 21h,#00h ;result
mov a,20hcpl ainc amov 21h,a ;result
loop: sjmp loop
Exercise 3:
Write a program to add two 16 bit numbers
Ans:;program to do 16 bit addition
org 00hmov r0,#0ffh ;First no HBmov r1,#0ffh ;first no LBmov
r2,#0ffh ;second no HBmov r3,#0ffh ;second no LB
;;;;;;;;;;;;;;;
-
8/8/2019 8051 Tutorials 2
81/94
;results are stored from R5 R6 R7 registers;;;;;;;;;;;;;;
mov a,r1 ;lower byte additionadd a,r3mov r7,a
mov a,r0 ;upper byte additionaddc a,r2mov r6,a
jnc nocarrymov r5,#01h
nocarry:loop: sjmp loop
Exercise 4
Write a program to subtract two 16 bit numbers
Ans:________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
______________________________________
Exercise 5
Write a program to multiply two 16 bit numbers
Ans.
________________________________________________________________________
-
8/8/2019 8051 Tutorials 2
82/94
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
____________________________________
Exercise 6
Write a program to convert binary to gray code
Ans:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
_________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Exercise 7
Find out the largest numbers stored in given memorylocations
Ans:
;the 10 numbers are stored in the internal ram from 20h
to29h
org 00h;-------------------------------------;store the list of
10 elements here;-------------------------------------mov 20h,#40h
;enter the data required
-
8/8/2019 8051 Tutorials 2
83/94
mov 21h,#23hmov 22h,#25hmov 23h,#98hmov 24h,#0a5hmov
25h,#0fahmov 26h,#56h
mov 27h,#77hmov 28h,#0ffhmov 29h,#7dh
mov r0,#20hmov a,@r0
up:mov 01h,@r0cjne a,01h,lesser_greatersjmp equal
lesser_greater:jnc smallermov a,01h
equal:smaller:inc r0
cjne r0,#2ah,uplast: sjmp last
;----------------------------;the largest no is in the
acc;----------------------------
Exercise 8
Sort the given numbers in i) ascending order ii)
Descendingorder
ans:________________________________________
____________________________________________
____________________________________________
____________________________________________
________________________________________________________________________________________
____________________________________________
____________________________________________
____________________________________________
-
8/8/2019 8051 Tutorials 2
84/94
____________________________________________
____________________________________________
____________________________________________
________________________________________________________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
____________________________________________
________________________________________________________________________________________
____________________________________________
________________________________________
-
8/8/2019 8051 Tutorials 2
85/94
Exercise 9
Generate 15us s/w time delay
;program to ilustrate the s/w delays
org 00h;acall delay15usacall delay1ms
loop: sjmp loop
;----------------------------------------------;delay of 15
micro sec including acall
;;-----------------------------------------------
delay15us: mov r0,#5decrement: djnz r0,decrement
ret
Generate 5u sec time delay
Ans:;--------------------------------------------;delay of 1m
and 5 micro sec including
acall;--------------------------------------------delay1ms: mov
r0,#250
up: nopnopdjnz r0,upret
Exercise 10
Write a program to blink a led
ans:;program to blink a led
org 00h
back: setb p1.0 ;led on
acall delay500ms
clr p1.0 ;led off
acall delay500ms
sjmp back
-
8/8/2019 8051 Tutorials 2
86/94
delay500ms: mov r7,#2
up2: mov r6,#249
up1: mov r5,#250
up: nop
nop
djnz r5,up
djnz r6,up1
djnz r7,up2
ret
Exercise 11
Write a program blink alternative leds connected to a port
ans:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________
_________________________________________________________
Exercise 12
Write a program to display number 0 t0 3ans:;program to make a
seven segment led to count 0 to 3
;negative logic COMMON_0 to Always 1
;;;;;; 1 switch off the segment
;;;;;; 0 switch on the segement
;8 segments connected to the 8 pins of the port 0
; eg p0.0 to a segment
;eg p0.1 to b segment etc..........
; 7 6 5 4 3 2 1 0
; pts g f e d c b a
; 0 1 0 0 0 0 0 0 display 0
; 0 1 1 1 1 0 0 1 " 1
; 0 0 1 0 0 1 0 0 " 2
; 0 0 1 1 0 0 0 0 " 3
-
8/8/2019 8051 Tutorials 2
87/94
org 00h
repeat: mov p0,#40h
acall delay
mov p0,#79h
acall delay
mov p1,#24h
acall delay
mov p2,#30h
acall delay
sjmp repeat
delay: mov r7,#2
up2: mov r6,#249
up1: mov r5,#250
up: nop
nop
djnz r5,up
djnz r6,up1
djnz r7,up2
ret
Exercise 13
Write a program to display ISM on alphanumeric displayAns:
;program to blink ISM on the alphanumeric display
;P0.0 - p0.6 connected to D0-D7 in the sequence;p1.0 - connected
for the A0 address lines
;p1.1 - connected for the A1 address lines
;p2.0 connected to write line which is active low
org 00h
;to display the character the left most
unit
;address is A1 A0 is 1 1
back: mov p1,#%00000011
mov P0,#'I'
clr P2.0setb p2.0
mov p1,#%00000010
mov P0,#'S'
clr P2.0
setb p2.0
mov p1,#%00000001
mov P0,#'M'
-
8/8/2019 8051 Tutorials 2
88/94
clr P2.0
setb p2.0
acall delay
;clears the all the four units
mov p1,#3
mov p0,#' '
clr p2.0
clear: djnz 90h,clear
setb p2.0
acall delay
sjmp back
delay: mov r7,#2
up2: mov r6,#249
up1: mov r5,#250
up: nop
nop
djnz r5,up
djnz r6,up1
djnz r7,up2
ret
Exercise 14
Write a program to scroll a string in alphanumeric display
modules________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
____________
Exercise 15
Generate time delay of 50 ms using timer 1, mode 1ans:;program
to do a delay of 50 ms
-
8/8/2019 8051 Tutorials 2
89/94
; to do 1 sec delay take out the comments at the line
number 7 and 13
org 00h
mov tmod,#10h
;mov r0,#20 ;7th line
up: mov th1,#3ch
mov tl1,#0b0h
setb tr1
wait: jnb tf1,wait
clr tr1
clr tf1
;djnz r0,up ;13th line
last: sjmp last
Exercise 16
generate square wave at pin number p0.0 using timer assource of
delay(use mode2,timer
0)ans:____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Exercise 17
Connect a rectangular signal generator at p3.4and find out the
frequency of the source by s/w
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
-
8/8/2019 8051 Tutorials 2
90/94
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
____________________________________
Exercise 18
communicate with the pc(hyper terminal) @9600 baud rate;program
to transmit the data to the pc at the 9600 bps
;set the crystal to 11.0592 mega hz
org 00h
mov scon,#40h ;mode 1, 8 bit UART, variable baud
rate
mov tmod,#20h ;timer 1 in auto reload mode
mov th1,#0fah ;9600 bs
mov tl1,#0fah
setb tr1 ;start the serial coimmunication
repeat:mov dptr,#data
back: clr a
movc a,@a+dptr
jz repeat
mov sbuf,a
wait: jnb TI,wait
clr TI
sjmp back
data: db 'Hello world',0
-
8/8/2019 8051 Tutorials 2
91/94
end
Exercise 19
connect a switch as source of external interrupt and onoccurance
of interrupt (on button press) blink a led asinterrupt service
routinans:
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
_________
Exercise 20
blink the led at equal interval of the timeuse timer1
interrupt.
-
8/8/2019 8051 Tutorials 2
92/94
Step 7. Open the 89S52 flash programmer
Step 8. Open the created hex file
-
8/8/2019 8051 Tutorials 2
93/94
Note 1. Make sure the serial cable and the power supply are
connected
Note 2. The DIP Switch should be in programming mode
-
8/8/2019 8051 Tutorials 2
94/94
Step 9. Click the write button on the flash programmer IDE
Step 10. After writing, click the read button and verify the hex
code.
Step 11. Reset the device and change the mode to normal
operation.
Step 12. View your output.
