DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING
MICRO CONTROLLER LAB MANUAL
FOR BE ¾ YEAR 2ND SEMESTER
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BE ¾ (ECE) 2nd 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 arithmetic operations, branching operations, 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 ¾ (ECE) 2ND SEMESTER MICRO CONTROLLER LAB LIST OF EXPERIMENTS Experiment No.1: Familiarity and use of 8051 (ESA-31) (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) Dire Direct ct add addre ress ssin ing g b) Regist Register er indirec indirectt addressi addressing ng c) Using Using loop loop struct structure ure.. Program 3: Sum of a series of byte elements Program 4: Copying a data block from f rom source to destination. Program 5: Count number of 1’s 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 3
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. 1 Familiarity 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 follows.
: Four 28-pin JEDEC sockets offer 120KB of memory as
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. 6
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 8
This command is used to examine and optionally modify the contents of some of the 8031/8051’s 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 user’s 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 them b) 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 GO<8000>EXEC press BREAK key. Press EXAMREG key twice to check result in regs R6 and R7 respectively. 10
Format: 6
2. Write an 8051 program to copy the value 55H into RAM memory
locations 40H to 44H using
A) Direct addressing mode B) 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 MOV 41h,A MOV 42h,A MOV 43h,A MOV 44h,A HERE : SJMP HERE
;copy A to RAM Location
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2.B) Using reg-indirect addressing mode without loop
MOV A.#55h MOV R0,#40h MOV @R0,A INC R0 MOV @R0,A INC R0 MOV @R0,A INC R0 MOV @R0,A INC R0 MOV @R0,A HERE :SJMP HERE 2) C) With Loop.
MOV A,#55h MOV R0,#40h MOV R2,#05h ;Counter AGAIN : MOV @R0,A INC R0 DJNZ 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 CLR A MOV R7, A AGAIN: ADD A, @R0 JNC NEXT INC R7 NEXT : INC R0 DJNZ R2, AGAIN MOV 60h, A MOV 61h, R7 HERE : SJMP HERE
; Counter ; initial sum=0 ; clear R7 to save carry
; Keep track of carries
; store LSBy of sum ; store MSBy of sum
1) Format: for entering, executing & Checking results.
Enter source code 8000 DATA ……. Feed Sample Data 50 DATA DATA…….. 60 00XT>00 Run the Program <8000> 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 MOV R1, #60h MOV R3, #0Ah BACK: MOV A,@R0 MOV @R1, A INC R0 INC R1 DJNZ R3, BACK HERE: SJMP HERE. 5.
; Source pointer ; destination pointer ; counter
A byte is stored in register R0. Write a 8051 Program to find the Number of 1’s in a byte stored in RO and Store the number of 1’s in register R2.
Let R0 = AAh
10101010
MOV R0, #AAh MOV A, R0 MOV R2, #00h MOV R1, #08h LOOP: RLC A JNC CONT INC 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, #8051H MOVX A,@DPTR MOV 0F0h, A MOV DPTR, #8050h MOVX A,@DPTR MUL AB MOV DPTR, #8060h MOVX @DPTR, A INC DPTR MOV A, 0F0h MOVX @DPTR, A HERE: SJMP HERE
; multiplier in B reg ; multiplicand in A reg
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, #50h MOV R2, #05h LOOP: CJNE @R1, #64H, CONT MOV 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 94h Result = (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
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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 CLR C CLR A
; COUNT = 4
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 20
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)
HERE:
ORL A, R2
; A=47H, packed BCD
MOV @ R1, A
; store packed BCD
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 MOV R2, A MOV R0, #40H ANL A, #0FH ORL A, #30 MOV R6, A MOV A, R2 ANL A, #0F0H SWAP A ORL A, #30H MOV R7, A MOV @R0, 06 INC R0 MOV @R0, 07 HERE: SJMP HERE
;A=29H,packed BCD ; copy of BCD data in R2 ;point to result location ;mask upper nibble ;make it an ASCII,A=39H ;save it ;get the packed BCD again ;mask lower nibble ;A=32H ;save ASCII ;store ASCII character ;in memory locations ; in memory locations
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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 00000110 2. Multiply BCD2 by 10 3. Add BCD1 to the answer in step2 Source code listing
MOV R0, #40H MOV R1, #50H MOV A, @R0 MOV R2, A ANL A, #0FH MOV R3, A MOV A, R2 ANL A, #0F0H SWAP A MOV 0F0H, #0AH MUL AB ADD A, R3 MOV @R1, A HERE : SJMP HERE.
;get packed BCD in A reg ;save it in R2 reg ;mask the lower nibble ;BCD1 IN R3 ;get packed BCD again ;mask the upper nibble ;BCD2 in A reg ;Reg B loaded with 10 decimal ;add to BCD1` ;store binary equivalent
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 = 500µs.
Delay time = T/2 = 250µs. 250µs/1.085µs = 230 clocks. 65536 – 230 = (65306)10 Initial count value = FF1A h TL1 = 1AH TH1 = FFH PROGRAM:
MOV TMOD, #10H
; timer1, mode1
AGAIN: MOV TL1, #1AH MOV TH1, #0FFH SETB TR1 BACK: JNB TF1, BACK
; Start timer 1 ; 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 = 500µs. Delay time = T/2 = 250µs. 250µs/1.085µs = 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.6 Communication 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 pack age XT51 which allow the user to establish serial communication between the trainer and a host PC thro its Asynchronous 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 directory C:\> 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 8000h CLR C Mov a ,#0E7h Add a,#8Dh Mov r6,a Mov a,#3ch Addc a,#3bh Mov r7,a Here :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 =N>:d Generate cross reference?=N>:n Input Filename : add16.asm Output Filename: 8051 CROSS ASSEMBLER-VERSION 4.00f Input Filename : add16.asm Output Filename : add16.obj Lines Assembled:________ Assembly Errors:_______ C:\51
Step4:Link the single file add16.obj Specify code offset and options H for HEX format. This process creates a hex file add16.hex that can download into ESA 31 kit. C:\51 link51 Linker copyright1985-version 4.00g Input Filename:add16.obj Enter Offset For ‘CODE’ Input Filename: Output Filename:
:
0
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 files Created for add 16 C:\51 dir Also check the list file for add16 as C:\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 LTD BANGALORE Press any Key to Continue _____________________________________________________________
XT51 Checks for the presence of communication ports COM1 and COM2 If 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+D Specify download filename Add16.hex Specify memory type Specify starting address Specify ending address Downloading program Run the program using G command as G 8000 Press Break Key
:P : 8000 :
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 40 40 XX 21 41 XX 22 43 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 LAB EXPERIMENT 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 kit 2. Dual channel DAC module 3. Power supply units 4. 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 E800H Port B Equ E801H Port C Equ E802H Port D Equ E803H Note: Port A controls Xout and Port B controls Yout of DAC interface module. PROGRAMS: 1. 2. 3. 4.
Write an ALP to generate Saw tooth (Up-going and down-going) Write an ALP to generate Triangular waveform. Write an ALP to generate Symmetrical Square wave. 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 PORT_A PORT_B PORT_C
EQU EQU EQU
8000H E800H E801H E802H
CWR EQU E803H ; Program to generate Continuous up going saw tooth. MOV MOV MOVX CLR AGAIN: MOV MOVX INC MOVX INC SJMP
DPTR,#0E803H A,#80H @DPTR,A ;initialize 8255A for mode 0 with PA&PB as OUT A ;Start with value 00H DPTR, #0E800H;Point to Port A @DPTR,A ;Out to Port A and DPTR @DPTR,A ;Out to Port B A ;increment DAC input AGAIN ;Repeat forever.
; Program to generate continuous down going Sawtooth MOV MOV MOVX MOV AGAIN: MOV MOVX INC MOVX DEC SJMP
DPTR,#0E803H A,#80H @DPTR,A A,#0FFH DPTR,#0E800H @DPTR,A DPTR @DPTR,A A AGAIN
; Program to generate continuous triangular waveform MOV MOV MOVX CLR UP: MOV MOVX INC MOVX INC CJNE DOWN :MOV MOVX INC MOVX DEC CJNE
DPTR,#0E803H A,#80H @DPTR,A A DPTR,#0E800H @DPTR,A DPTR @DPTR,A A A,#0FFH,UP DPTR,#0E800H @DPTR,A DPTR @DPTR,A A A,#00H,DOWN
SJMP UP ; Program to generate Symmetrical Square Wave MOV MOV MOVX BACK:MOV MOV MOVX MOV DLY1:DJNZ MOV MOVX MOV DLY2:DJNZ SJMP
DPTR,#0E803H A,#80H @DPTR,A A,#0FFH DPTR,#0E800H @DPTR,A R0,#0FFH R0,DLY1 A,#00H @DPTR,A R0,#0FFH R0,DLY2 BACK
; Program for Stair case (Up-going) with 5 steps. MOV MOV MOVX MOV RPT: ADD MOV MOVX MOV DLY1: DJNZ CJNE INC MOVX MOV DLY2: DJNZ SJMP
DPTR,#0E803H A,#80H @DPTR,A A,#00H A,#33H DPTR,#0E800H @DPTR,A R0,#0FFH R0,DLY1 A,#0FFH,RPT A @DPTR,A R0,#0FFH R0,DLY2 RPT
; Program for Stair case (down-going) with 5 steps MOV MOV MOVX MOV MOV RPT: MOVX MOV DLY1: DJNZ AGAIN:CLR
DPTR,#0E803H A,#80H @DPTR,A A,#0FFH DPTR,#0E800H @DPTR,A R0,#0FFH R0,DLY1 C
SUBB MOVX MOV DLY2: DJNZ CJNE DEC SJMP
A,#33H @DPTR,A R0,#0FFH R0,DLY2 A,#00H,AGAIN A RPT
EXPERIMENT NO.8 Interfacing 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 RED A = SOUTH AMBER L = SOUTH LEFT S= SOUTH STRAIGHT Rg=SOUTH RIGHT DL=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 PORT B:
EA
ERg
EL
SR
SA
SRg
SL
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 WEST Vehicles from WEST can go NORTH Vehicles from NORTH can go SOUTH Pedestrians can cross on EAST 2. Vehicles from EAST can go WEST and SOUTH Vehicles from WEST can go EAST Vehicles from SOUTH can go WEST Pedestrians can cross on NORTH 3. Vehicles from EAST can go SOUTH Vehicles from NORTH can go SOUTH and EAST Vehicles from SOUTH can go NORTH Pedestrians can cross on WEST 4. Vehicles from EAST can go WEST
Vehicles from WEST can go EAST and NORTH Vehicles from NORTH can go EAST Pedestrians can cross on SOUTH 5. No vehicle movement Pedestrians 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 PORTA PORTB PORTC CWR MOV MOV MOVX AGAIN: MOV NEXTST: MOVX PUSH PUSH MOV MOVX POP POP INC MOVX PUSH PUSH MOV MOVX POP POP INC MOVX PUSH PUSH MOV MOVX POP
EQU EQU EQEU EQU
8000H E800H E801H E802H E803H
DPTR,#0E803H A,#80H @DPTR,A DPTR,#PORTS A,@DPTR DPL DPH DPTR,#0E800H @DPTR,A DPH DPL DPTR A,@DPTR DPL DPH DPTR,0E801H @DPTR,A DPH DPL DPTR A,@DPTR DPL DPH DPTR,#0E802H @DPTR,A DPH
;Port A value.
;Port B value.
;Port C value.
