DEPARTMENTOF

ELECTRONICS AND COMMUNICATIONENGINEERING

MICRO CONTROLLERLAB MANUAL

FOR

BE YEAR 2ND SEMESTER

1

BE (ECE) 2 nd Semester

MICRO CONTROLLER LAB

LIST OF EXPERIMENTS

Exp No. 1- Familiarity and use of 8051 Micro controller Trainer.

Exp No. 2- Instruction set for simple programs for data transfer,& 3 manipulation, arithmetic operations, branching operations, logical operations and testing condition of bit in a byte.

Exp No. 4- Code conversion programs.

Exp No. 5- Timer and counter programming using 8051

Exp No. 6- Serial mode operation of 8051

Exp No. 7- Interfacing DAC module using 8051

Exp No. 8- Interfacing Traffic signal control using 8051

Exp No. 9- Interfacing 7-segment display using 8051

Exp No.10-Interfacing Stepper motor control using 8051

Exp No.11-Familiarity with MCBX51 board and writing programs for MCBX51. Program for Blinking of LEDs.

Exp No.12-Real time clock using 8051.

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BE (ECE) 2 ND SEMESTER

MICRO CONTROLLER LAB

LIST OF EXPERIMENTS

Experiment No.1:

Familiarity and use of 8051 (ESA-31) Micro controller kit trainer.

Experiment No.2:

Simple programs in 8051 Assembly code and their execution.

Program 1: Addition of two 16 bit numbers using registers.

Program 2: Copying of byte data in RAM memory locations using a) Direct addressingb) Register indirect addressingc) Using loop structure.

Program 3: Sum of a series of byte elements

Program 4: Copying a data block from source to destination.

Program 5: Count number of 1s in a byte.

Program 6: Multiplication of two unsigned 8-bit binary numbers.

Program 7: Division of two unsigned 8-bit binary numbers.

Program 8: Searching of a byte element in a data block.

Experiment No.3:

Arithmetic, Logical & Branching operations.

Program 9: Multi byte binary addition

Program 10: Multi byte BCD addition

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Program 11: Multi byte binary subtraction

Program 12: Testing condition of a bit in a byte of data.

Program 13: Finding largest element in a block of data array.

Program 14: Checking a character string for a palindrome.

Experiment No. 4:

Code conversion Programs.

Program 15: ASCII to Packed BCD conversion.

Program 16: Packed BCD to ASCII conversion.

Program 17: BCD to Binary conversion.

Experiment No. 5:

Timer Programming using 8051

Experiment No. 6:

Communication with host computer system.

Experiment No. 7:

Interfacing of DAC using 8051 and its programming.

Experiment No. 8:

Interfacing of traffic signal control using 8051 and its programming.

Experiment No. 9:

Interfacing of 7-segment display using 8051 and its programming.

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Experiment No. 10:

Program to control Stepper motor using 8051 .

Experiment No. 11:

Introduction to KEIL Software and MCBX51 kit.

Experiment No. 12:

Blinky : LED flasher program.

Experiment No. 13:

Interfacing elevator simulator control using 8051.

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EXPERIMENT NO. 1Familiarity with ESA 31 micro controller kit:

Main features of ESA 31 (8031 based):

ESA 31 can be operated either from on board keyboard or from a CRT terminal through its RS 232-C interface.

Keyboard and serial monitor programs support the entry of users program, editing, debug facilities like breakpoints & single stepping, & full execution of user programs.

1-pass Assembler can assemble any memory resident assembly language program.

1-pass Dis assembler dis assembles the object code into standard INTEL mnemonics.

Total of 120KB memory is provided of which 64KB of memory is program memory and 56KB of memory is data memory.

The monitor of the trainer occupies 32KB out of 64KB of program memory.

Standard bus compatible signals available on the bus connector for easy expansion.

SPECIFICATIONS:

Microcontroller: 8031/8051 operated at 11.0592 MHz

Memory : Four 28-pin JEDEC sockets offer 120KB of memory as follows.

32KB of firmware in one 27256 (Program memory)

32KB of SRAM using one 62256 (User program memory)

56KB of SRAM as data memory using two 62256s.

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The memory map is as follows:

DEVICE ADDRESS RANGE TYPE OF MEMORY

27256 0000-7FFF Program memory

62256 8000-FFFF User program memory

62256 0000-7FFF User data memory

62256 8000-DFFF User data memory.

The dip switch settings for either mode of operation are as follows:

For Hexadecimal keypad mode: All switches in OFF position.

For Serial mode : Switches 1 and 4 in ON position.

KEYBOARD MONITOR

In the keyboard mode, the user enters the commands and data by pressing the appropriate keys on the keypad. Responses are displayed by the system on the seven-digit 7-segment LED display.

The RESET key causes a hardware reset and restarts the monitor. The monitor displays the sign-on message ESA 51 across the address & data fields of the display.

KEYBOARD & DISPLAY

The display consists of 7 seven segment LED displays, separated into three fields. The leftmost single digit forms the special field. Next four digits form the address field.Note: address can be 64KB or 256B max.

Last two digits form the data field.

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The 36 key keypad consists of the following group of keys.

A). Hex pad 16 keys representing hex digits 0 through F.

B). Command Group 13 command keys.

C). Memory Group 4 keys (PRGMEM, EXTDATA, BITMEM, INTDATA) to select the type of memory.

D). System Operation keys RESET, BREAK, and EXEC keys

BREAK can be used to stop the execution without affecting the register contents.

MONITOR COMMANDS

The keyboard monitor is capable of executing fifteen individual commands.

EXAMINE/MODIFY MEMORY

Displays/modifies the contents of a memory location.Syntax Format:

EXAM MEM {PRG MEM/EXT DATA/BIT MEM/INT DATA}Addr1 NEXT [[[data] NEXT/PREV].] EXEC

After pressing EXAM MEM key, enter the type of memory by pressing PRGMEM, EXTDATA, BITMEM, or INTDATA key.

A dot appears at the last digit of the address field indicating that an address entry is required.

Enter the memory address of the byte to be examined. (Memory address are evaluated modulo 64K if it is program memory or data memory and modulo 256 if it is internal data memory or bit memory).

The value is displayed in the address field of the display.

EXAMINE/MODIFY REGISTER

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This command is used to examine and optionally modify the contents of some of the 8031/8051s registers.

EXAM REG [reg key] [[Data] NEXT/PREV].] EXEC.

Note: When any of the registers R0-R7 has to be examined, press EXAMREG key and then BITMEM key. Now press keys 0-7 on the hex keypad, which corresponds to registers R0-R7.

The displayed registers contents of R0-R7 is w.r.t the current bank selected.

GO COMMAND:

Is used to transfer control of the system from the monitor to the users program.

GO [Starting addr] EXEC

To abort execution of user program press RESET key. By doing so all registers information about user program is lost. In any case, contents of the user portion of the RAM area are not altered by the monitor.

There are two ways to break the user program execution.

a) Set breakpoints at specific addresses, and enable themb) Press BREAK key.

If BREAK key is pressed, control returns to the monitor which saves all the registers and displays the address where the program broke and the data at that address on the display. It displays U on the special field of 7-segment display.

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EXPERIMENT NO 2 & 3

Execution of simple programs using ESA-31 in keyboard mode.

Program Examples:

1. Write a program in 8051 to add two 16-bit numbers.The numbers are 3CE7H and 3B8DH. Place the sum in registers R7 and R6; R6 has the lower byte.

Address OBJECT Code Mnemonic

8000 C3 CLR C

8001 74 E7 MOV A, #0E7H

8003 24 8D ADD A, #8DH

8005 FE MOV R6, A

8006 74 3C MOV A, #3CH

8008 34 3B ADDC A, #3BH

800A FF MOV R7, A

800B 80 FE HERE:SJMP HERE

(Relative address = Target address PC contents )

Enter the codes using the format given below.

8000 DATA ..EXEC

Note: After executing the program using GOEXEC press BREAK key. Press EXAMREG key twice to check result in regs R6 and R7 respectively.

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Format:

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2. Write an 8051 program to copy the value 55H into RAM memory locations 40H to 44H using

A) Direct addressing modeB) Register addressing mode without using Loop and C) With a Loop.

3. Six bytes of data are stored in memory locations starting at 50H. Add all the bytes. Use reg R7 to save any carries gtenerated. Store the sum at memory locations 60H&61H.

(50) = 10h, (51) = 25H, (52) = 2AH, (53) = 4FH, (54) = 60H, (55) = 3FH

2) A)Using direct addressing mode MOV A,#55h

MOV 40h,A ;copy A to RAM LocationMOV 41h,AMOV 42h,AMOV 43h,AMOV 44h,A

HERE : SJMP HERE

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2.B) Using reg-indirect addressing mode without loop

MOV A.#55hMOV R0,#40hMOV @R0,AINC R0MOV @R0,AINC R0MOV @R0,AINC R0MOV @R0,AINC R0MOV @R0,A

HERE :SJMP HERE

2) C) With Loop.

MOV A,#55hMOV R0,#40hMOV R2,#05h ;Counter

AGAIN : MOV @R0,AINC R0DJNZ R2,AGAIN

HERE :SJMP HERE

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3) Sample data: (50) =10h, (51)=25h, (52)=2AH, (53)=4Fh, (54)=60h,

(55)=3Fh Result = (60)=4Dh

(61)=01h (MS byte) 014Dh

Source Code

MOV R0, #50h MOV R2, #06h ; Counter CLR A ; initial sum=0 MOV R7, A ; clear R7 to save carry

AGAIN: ADD A, @R0 JNC NEXT INC R7 ; Keep track of carries

NEXT : INC R0 DJNZ R2, AGAIN MOV 60h, A ; store LSBy of sum MOV 61h, R7 ; store MSBy of sum

HERE : SJMP HERE

1) Format: for entering, executing & Checking results.

Enter source code 8000 DATA .

Feed Sample Data 50 DATA DATA..

60 00XT>00

Run the Program Reset Check Results 60 .

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4. Write an 8051 program to copy a block of 10 bytes of data from RAM locations starting at 35h to RAM locations starting at 60h.

Sample Prob Source block

(35)=10h, (36) =20h, (37) = 30h, (38) = 40h, (39) = 50h, (3A) = 60h, (3B) = 70h, (3C) = 80h, (3D) = 90h, (3E) =A0h

MOV R0, #35h ; Source pointer MOV R1, #60h ; destination pointer MOV R3, #0Ah ; counter

BACK: MOV A,@R0 MOV @R1, A INC R0 INC R1 DJNZ R3, BACK

HERE: SJMP HERE.

5. A byte is stored in register R0. Write a 8051 Program to find the Number of 1s in a byte stored in RO and Store the number of 1s in register R2.

Let R0 = AAh 10101010

MOV R0, #AAhMOV A, R0MOV R2, #00hMOV R1, #08h

LOOP: RLC AJNC CONTINC R2

CONT: DJNZ R1, LOOP HERE: SJMP HERE

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6. Write a 8051 program to multiply two unsigned 8-bit binary Numbers. The numbers are stored in memory locations 8050h and 8051h. Store the result in 8060h and 8061h.

Sample data: (8050)= 41h (65)10

(8051)= 08h(8060)= 08h(8061)= 02h

i.e. 65X8 = (520)10 = 0208h

MOV DPTR, #8051HMOVX A,@DPTRMOV 0F0h, A ; multiplier in B regMOV DPTR, #8050h MOVX A,@DPTR ; multiplicand in A regMUL ABMOV DPTR, #8060hMOVX @DPTR, AINC DPTRMOV A, 0F0hMOVX @DPTR, A

HERE: SJMP HERE

7. Division of two unsigned 8-bit binary numbers.

Divide the number in 8050h by the number in 8051h.Store the quotient and remainder in 8060h & 8061h of data memory respectively.

Sample data: (8050) =41h dividend (8051)=08h divisor

Result : (8060) =08h quotient (8061)=01h reminder

Hint: Similar to multiplication program. Store initial divisor in B reg and dividend in A reg. Use instruction DIV AB in place of MUL AB, After division operation, quotient is in A reg & remainder is in B reg.

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8. Write a 8051 program to find the number 64h from the set of five Readings starting from address location 50H to 54h. If present store 00h in R0,otherwise store FFh in R0.

Sample Problem (1):

i) (50) =76h, (51) =45h, (52) =64h, (53) =25h, (54) =22h. Result = (R0) =00h

MOV R1, #50hMOV R2, #05h

LOOP: CJNE @R1, #64H, CONTMOV R0, #00h

HERE1: SJMP HERE1 CONT: INC R1 DJNZ R2, LOOP

MOV R0, #FFh HERE2: SJMP HERE2

Sample prob (2)Replace data in (52) by 94hResult = (R0) =FFh.

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Program No 9: Multi byte Binary Addition.

Write a Program to add 4627342AH to 32B35642H.The two binary strings starts (LSB first) in RAM memory 20H and 30H respectively and save the result in RAM Memory locations starting at 30H replacing the second binary string.

Sample Proof: - 4627342A H +32B35642 H

78DA8A6CH

Sample data.

(20) =2AH, (21) =34H, (22) =27H, (23) =46H(30) =42H, (31) =56H, (32) =B3H, (33) =32H

Result= (30) =6CH, (31) =8AH, (32) =DAH, (33) =78H.

Source Code Listing

MOV R0, #20H MOV R1, #30H MOV R3, #04H; Count=4 CLR C CLR A

AGAIN: MOV A,@R0 ADDC A,@R1 MOV @R1, A INC R0

/ INC R1 DJNZ R3, AGAIN

HERE: SJMP HERE.

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Program N0 10: Multi byte BCD Addition.

Write a Program to add 4 byte packed BCD 46273420H to 32105644H and save the BCD result in RAM memory locations starting at 30H. The two BCD Strings starts (LSB first) from RAM Locations 20H & 30H respectively.

46273420 +32105644

78379064 Source code listing

MOV R0, #20H MOV R1, #30H MOV R3, #04H; COUNT=4 CLR C CLR A

AGAIN: MOV A,@R0

ADDC A,@R1

DAA

MOV @R1, A

INC R0

INC R1

DJNZ R3, AGAIN

HERE: SJMP HERE.

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Program No 11: Multi byte Binary Subtraction

Write a Program to subtract 14DF35B8H from 2F5BA7C3H, and save the result in RAM memory location Starting at 30H.The two binary strings starts(LSB first)from RAM location 20H & 30H respectively

2F5BA7C3H- 14DF35B8H 1A7C720BH

Source code listing

MOV R0, #20H MOV R1, #30H MOV R3, #04H ; COUNT = 4 CLR C CLR A

AGAIN: MOV A,@R0 SUBB A,@R1 MOV @R1, A INC R0 INC R1

DJNZ R3, AGAIN HERE: SJMP HERE.

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Program No 12: Checking a character string for a Palindrome.

Write a program to check if the character string of length 7, stored in

RAM locations 50H onwards is a Palindrome. If it is, output Y to P1.

Solution:

A Palindrome is a string in which the characters are the same whether the

string is read in the forward or backward direction. Example, MADAM,

RADAR.

MOV R2, #03 ; take half the string length as counter value

MOV R0, #50H ; take R0 as pointer to the forward reading

MOV R1, #56H ; take R1 as pointer for the backward reading Of the string

Back: MOV A, @R0 ; move into A the character pointed by R0

MOV B, @R1 ; move into B the character pointed by R1

CJNE A, B, NEXT ;compare it with the character pointed by R1

INC R0 ; increment the forward counter

DEC R1 ; decrement the backward counter

DJNZ R2, BACK ; repeat until all characters are compared

MOV P1, #Y ; since the string is a Palindrome output Y

NEXT: NOP ; if not equal, do nothing since it is not a Palindrome

END

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EXPERIMENT -4

CODE CONVERSION

2) ASCII to Packed BCD Conversion

Write a program to convert two ASCII decimal digits available in RAM locations 30H and 31H into packed BCD number and store the result in RAM location 40H.

Sample data:- (30) =34H 4

(31)=37H 7

Result= (40) =47H (packed BCD)

Source code listing

MOV R0, #30H

MOV R1, #40H

MOV A,@R0

ANL A, #0FH ; mask upper nibble (A=04H)

SWAP A : A=40H

INC R0

MOV 02H,@R0

ANL R2, #0FH; mask upper nibble (R2=07H)

ORL A, R2 ; A=47H, packed BCD

MOV @ R1, A ; store packed BCD

HERE: SJMP HERE.

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2) Packed BCD to ASCII Conversion

PROGRAM:

Assume that register A has Packed BCD ,write a program to convert packed BCD to two ASCII numbers and place them in RAM memory location 40H and 41H respectively.

Source code listing

MOV A, #29H ;A=29H,packed BCDMOV R2, A ; copy of BCD data in R2MOV R0, #40H ;point to result locationANL A, #0FH ;mask upper nibble

ORL A, #30 ;make it an ASCII,A=39HMOV R6, A ;save itMOV A, R2 ;get the packed BCD againANL A, #0F0H ;mask lower nibbleSWAP AORL A, #30H ;A=32HMOV R7, A ;save ASCIIMOV @R0, 06 ;store ASCII characterINC R0 ;in memory locationsMOV @R0, 07 ; in memory locations

HERE: SJMP HERE

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3) BCD to binary Conversion

PROGRAM Sample example (40) = 6910 (packed BCD)

Result= (50) = 45H (Binary equivalent)Steps.

1. Split the packed BCD into unpacked BCD digit BCD1 & BCD2 01101001 BCD1 00001001

BCD2 000001102. Multiply BCD2 by 103. Add BCD1 to the answer in step2

Source code listing

MOV R0, #40HMOV R1, #50HMOV A, @R0 ;get packed BCD in A regMOV R2, A ;save it in R2 regANL A, #0FH ;mask the lower nibbleMOV R3, A ;BCD1 IN R3MOV A, R2 ;get packed BCD againANL A, #0F0H ;mask the upper nibbleSWAP A ;BCD2 in A reg MOV 0F0H, #0AH ;Reg B loaded with 10 decimalMUL ABADD A, R3 ;add to BCD1`MOV @R1, A ;store binary equivalent

HERE : SJMP HERE.

EXPERIMENT NO. 5

TIMER PROGRAMMING USING 8051

Task:

Assuming XTAL = 11.0592MHz, write a program for timer 1 in mode 1 to generate a square wave of 2KHz frequency on Pin P1.5 (Pin No. 6) GND (Pin 20)

Steps:T = 1/f = 1/2 KHz = 500s.

Delay time = T/2 = 250s.

250s/1.085s = 230 clocks.

65536 230 = (65306)10

Initial count value = FF1A hTL1 = 1AHTH1 = FFH

PROGRAM:

MOV TMOD, #10H ; timer1, mode1

AGAIN: MOV TL1, #1AH

MOV TH1, #0FFH

SETB TR1 ; Start timer 1

BACK: JNB TF1, BACK ; Stay until timer rolls over

CLR TR1 ; Stop timer

CPL P1.5 ; complement P1.5 to get HI, LO

CLR TF1 ; clear timer flag

SJMP AGAIN ; reload timer

Note: SFR address of TMOD = 89H, TL1 = 8BH, TH1 = 8DH, TR1 = 8EH, TF1 = 8FH, P1.5 = 95H.Note: Observe the output waveform across Pin 6 & 20 on CRO; and note down time period.

Write a program using timer 1 to generate a square wave of 2KHz frequency on Pin P1.5 (Pin 6) in mode 2 configuration (auto reload mode) GND (Pin 20)

XTAL = 11.0592 MHz

T = 1/f = 500s.

Delay time = T/2 = 250s.

250s/1.085s = 230 clocks.

256 230 = (26)10 = 1A H

Load TH1 with initial count value of 1AH.

PROGRAM:

MOV TMOD, #20h; timer1, mode2

MOV TH1, #1Ah

SETB TR1

BACK: JNB TF1, BACK

CPL P1.5

CLR TF1

SJMP BACK; mode 2 is auto reload.

Note: Observe the output waveform across Pin 6 & 20 on CRO; and note down time period.

Experiment No.6Communication with a Host Computer System

ESA 31 operating in the serial mode, can be connected to either a CRT terminal or a host computer system.

When a computer system is the controlling element, it must be executing driver software to communicate with the ESA 31 target kit.

ESA 31 is supplied with DOS communication driver package XT51 which allow the user to establish serial communication between the trainer and a host PC thro itsAsynchronous com ports (COMI and COM2).

INSTALLATION

a) Configure ESA 86/88E for serial mode of operation and set the serial port of ESA 86/88E for 9600 Baud rate and No parity(keep DIP switches 1 and 4 in ON position)

b) Connect the PC to ESA 31 trainer over COM1/COM2 serial port using the RS232C serial interface cable connecter.

The Serial mode of operation

a) Supports for downloading user programs in to the target ESA 31 kit from a Host computer system in INTEL HEX format.

b) Also supports for uploading user program to host PC and saving them as HEX files o a system.

Using of X8051 Cross Assembler

A convenient way of creating a file to be downloaded in to ESA31 is to use a cross assembler for 8051 that can generate the object code in extended HEX format. X8051 is such a package.

It is a powerful cross assembler for 8051. It can run on any PC/XT/AT compatible system and supports all the standard mnemonics, pseudo opcodes (directives) and addressing modes of 8051.

Steps involved in creating a HEX file are as follows:-

Step1:-Select the path folder directoryC:\> cd C:\> cd51

C:\> edit filename

Step2:-

Create a source file using the DOS text editor and save it as filename.asm.

Example:Write a source program for 16 bit addition using DOS text editor. The

numbers are 3CEH and 3B8DH. Place the sum in R7 and R6; R6 should have the lower byte.

Org 8000hCLR CMov a ,#0E7hAdd a,#8DhMov r6,aMov a,#3chAddc a,#3bhMov r7,aHere :sjmp here

Save and exit from editor,Let the source file be saved as add 16.asm

Step3:-

Assemble the source file add16.asm using X8051 to create an object file add16.obj as follows

C:\51 x8051

Listing destination :d

Generate cross reference?:n

Input Filename : add16.asm

Output Filename:

8051 CROSS ASSEMBLER-VERSION 4.00fInput Filename : add16.asmOutput Filename : add16.obj

Lines Assembled:________ Assembly Errors:_______C:\51

Step4:-Link the single file add16.objSpecify code offset and options H for HEX format.This process creates a hex file add16.hex that can download intoESA 31 kit.

C:\51 link51

Linker copyright1985-version 4.00gInput Filename:add16.obj

Enter Offset For CODE : 0Input Filename:Output Filename:

Options(D,S,A,M,X,H,E,T,1,2,3,(CR)=Default):h

Link Errors:________ Output Format:_______

C:\51

Step5:-(Optional)Check the directory to see the filesCreated for add 16C:\51 dir

Also check the list file for add16 asC:\51 edit add16.list

Step6:-Set the system in the serial communication mode using the XT51 command

C:\86>xt51

Now the following message will appears on the Screen__________________XT51 Version x, y_____________________

ELECTRO SYSTEM ASSOCIATES PVT LTDBANGALORE

Press any Key to Continue_____________________________________________________________

XT51 Checks for the presence of communication ports COM1 and COM2If Serial communication is established successfully the command

prompt . Appears on the screen otherwise the communication parameters are set appropriately using ALT+S command and continue.

Subsequently during the POWER ON RESET, the following sign on message appears on the screen followed by command prompt.

ESA 31 MONITOR VERSION x.y

Step7:-Download the program hex file from host PC to ESA 51 trainer using the CTRL+D command

CTRL+DSpecify download filenameAdd16.hex

Specify memory type : PSpecify starting address : 8000Specify ending address :

Downloading programRun the program using G command as

G 8000Press Break Key

Note:If input data is to be entered use >md commands to enter the data.Press ESC key to return to command Prompt. >

Use the M (Modify memory) command to examine the contents of specified memory locations.Further, if the locations are in RAM, their contents can be altered if desired.

Format: - M {P|D|I|B} addresses 1[address 2]

Ex 1: Examine a series of RAM locations starting at 8820H and modify the contents of the location 8822H.

>MD88220 88220 XX 88221 XX 88222 XX 55> 88220 XX

EX 2:To enter data at int RAM locations starting at 40H.

>MI 4040 XX 2141 XX 2243 XX 55>44 XX

(2) M (Display Memory) Command.This command is used to display the contents of the Program or

External or Internal Memory.

Foramt:M {P|D|I}, address1.address2

EX:To display the Contents of 5 Bytes from location 8020H.>Md8020, 8024.

MICROCONTROLLER LABEXPERIMENT NO.6

Generation of Waveforms using DAC interface module

AIM:To write and execute program in 8051 assembly language for interfacing a DAC

interface module with ESA 31 microcontroller trainer kit.

APPARATUS:1. ESA 31 Microcontroller trainer kit2. Dual channel DAC module3. Power supply units4. 26 Pin connector cable 5. CRO

DESCRIPTION:To use DAC, initialize 8255A for mode 0 operation with port A and port B as

output. Output data on the appropriate port and observe output wave form at Xout and Yout of the DAC using CRO.

The 16 bit port addresses for 8255A available at J2 connector are:Port A Equ E800HPort B Equ E801HPort C Equ E802HPort D Equ E803H

Note: Port A controls Xout and Port B controls Yout of DAC interface module.

PROGRAMS:

1. Write an ALP to generate Saw tooth (Up-going and down-going)2. Write an ALP to generate Triangular waveform.3. Write an ALP to generate Symmetrical Square wave.4. Write an ALP to generate

A). Up going stair case with 5 steps.B). Down going stair case with 5 steps.

Program 7.1

; Assume the DAC interface is connected over J2 of the ESA 31 trainer.

ORG 8000HPORT_A EQU E800HPORT_B EQU E801HPORT_C EQU E802H

CWR EQU E803H; Program to generate Continuous up going saw tooth.

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,A ;initialize 8255A for mode 0 with

PA&PB as OUTCLR A ;Start with value 00H

AGAIN: MOV DPTR, #0E800H;Point to Port AMOVX @DPTR,A ;Out to Port A and INC DPTRMOVX @DPTR,A ;Out to Port BINC A ;increment DAC inputSJMP AGAIN ;Repeat forever.

; Program to generate continuous down going Sawtooth

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,AMOV A,#0FFH

AGAIN: MOV DPTR,#0E800HMOVX @DPTR,AINC DPTRMOVX @DPTR,ADEC ASJMP AGAIN

; Program to generate continuous triangular waveform

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,ACLR A

UP: MOV DPTR,#0E800HMOVX @DPTR,AINC DPTRMOVX @DPTR,AINC ACJNE A,#0FFH,UP

DOWN :MOV DPTR,#0E800HMOVX @DPTR,AINC DPTRMOVX @DPTR,ADEC ACJNE A,#00H,DOWN

SJMP UP; Program to generate Symmetrical Square Wave

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,A

BACK:MOV A,#0FFHMOV DPTR,#0E800HMOVX @DPTR,AMOV R0,#0FFH

DLY1:DJNZ R0,DLY1MOV A,#00HMOVX @DPTR,AMOV R0,#0FFH

DLY2:DJNZ R0,DLY2SJMP BACK

; Program for Stair case (Up-going) with 5 steps.

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,AMOV A,#00H

RPT: ADD A,#33HMOV DPTR,#0E800HMOVX @DPTR,AMOV R0,#0FFH

DLY1: DJNZ R0,DLY1CJNE A,#0FFH,RPTINC AMOVX @DPTR,AMOV R0,#0FFH

DLY2: DJNZ R0,DLY2SJMP RPT

; Program for Stair case (down-going) with 5 steps

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,AMOV A,#0FFHMOV DPTR,#0E800H

RPT: MOVX @DPTR,AMOV R0,#0FFH

DLY1: DJNZ R0,DLY1 AGAIN:CLR C

SUBB A,#33HMOVX @DPTR,AMOV R0,#0FFH

DLY2: DJNZ R0,DLY2CJNE A,#00H,AGAINDEC ASJMP RPT

EXPERIMENT NO.8Interfacing of Traffic Light Controller Using 8051

The traffic light interface simulates the control and operation of traffic lights at a junction of four roads. The interface provides a set of 6 LED indicators at each of the four corners. Each of these LED s can be controlled by a port line. Thus the interface allows the user to simulate a variety of traffic simulations using appropriate software routines.

DESCRIPTION OF THE CIRCUIT :

The organization of 6 LED s is identical at each of the four corners. The organization with reference to the LED s at South-West corner is shown in figure.1

R = SOUTH REDA = SOUTH AMBERL = SOUTH LEFTS= SOUTH STRAIGHTRg=SOUTH RIGHTDL=SOUTH PEDESTRIAN

The five LED s (except Pedestrian) will be ON or OFF depending on the state of corresponding port line LED is ON, if the Port line is Logic HIGH and LED is OFF, if it is at logic LOW. The last LED marked DL is a set of two dual color LED s and they

both will be either RED or GREEN depending on the state of the corresponding port line RED if the port line is logic HIGH and GREEN if the port line is logic LOW.

24 LEDS AND CORRESPONDING PORT LINES:

PORT A:

D7 D6 D5 D4 D3 D2 D1 D0_____________________________________________

ER EA ERg EL SR SA SRg SL

PORT B:

D7 D6 D5 D4 D3 D2 D1 D0_____________________________________________

WR WA WRg WL NR NA NRg NL

PORT C:

D7 D6 D5 D4 D3 D2 D1 D0____________________________________________

EP SP WP NP SS ES NS WS

There are four such sets of LED s and these are controlled by 24 port lines of 8255A. Each port line is inverted and buffered using 7406 (open collector inverter buffers) and is used to control an LED. Dual color LEDs are controlled by a port line and its complement.

INSTALLATION:

The interface module has 26 pin connector at one edge of the card. This is used for connecting the interface over J2 of the ESA 31 trainer. The trainer can be in KEYBOARD MODE or SERIAL MODE.

PROBLEM STATEMENT:

Generate the sequence for PA, PB, and PC such that the following traffic situations are simulated.

1. Vehicles from SOUTH can go NORTH and WESTVehicles from WEST can go NORTHVehicles from NORTH can go SOUTHPedestrians can cross on EAST

2. Vehicles from EAST can go WEST and SOUTHVehicles from WEST can go EASTVehicles from SOUTH can go WESTPedestrians can cross on NORTH

3. Vehicles from EAST can go SOUTHVehicles from NORTH can go SOUTH and EASTVehicles from SOUTH can go NORTHPedestrians can cross on WEST

4. Vehicles from EAST can go WEST

Vehicles from WEST can go EAST and NORTHVehicles from NORTH can go EASTPedestrians can cross on SOUTH

5. No vehicle movementPedestrians can cross on all four roads.

The system moves from one state to another state after fixed time delay. The state transition is indicated by turning ON all the AMBER LEDs and all Pedestrians RED LEDs for a fixed duration. The sequence of the above states is repeated again and again.

; Program memory from 8000H to 804FH

ORG 8000HPORTA EQU E800HPORTB EQU E801HPORTC EQEU E802HCWR EQU E803H

MOV DPTR,#0E803HMOV A,#80HMOVX @DPTR,A

AGAIN: MOV DPTR,#PORTS NEXTST: MOVX A,@DPTR

PUSH DPLPUSH DPHMOV DPTR,#0E800H ;Port A value.MOVX @DPTR,APOP DPHPOP DPLINC DPTRMOVX A,@DPTRPUSH DPLPUSH DPHMOV DPTR,0E801H ;Port B value.MOVX @DPTR,APOP DPHPOP DPLINC DPTRMOVX A,@DPTRPUSH DPLPUSH DPHMOV DPTR,#0E802H ;Port C value.MOVX @DPTR,APOP DPH

POP DPLINC DPTRLCALL DELAY ;Provide delayMOV A,DPLCJNE A,#1EH,NEXTSTSJMP AGAIN

DELAY: MOV R2,#06 ;Delay routine LOOP3: MOV R4,#0FFH LOOP2: MOV R3, #0FFH LOOP1: DEC R3

CJNE R3,#00,LOOP1DEC R4CJNE R4,#00,LOOP2DEC R2CJNE R2,#00,LOOP3RET

; Enter the data mentioned below from 0000H to 001EH in data memory.

PORTS: DB 10H, 81H, 7AH ;state 1DB 44H, 44H, 0F0H ;All Ambers ONDB 08H, 11H, 0E5H ;State 2DB 44H, 44H, 0F0H ;All Ambers ONDB 81H, 10H, 0DAH ;State 3DB 44H, 44H, 0F0HDB 11H, 08H, 0B5H ;State 4DB 44H, 44H, 0F0HDB 88H, 88H, 00H ;State 5DB 44H, 44H, 0F0DB 00H ;Dummy