microprocessor sys lab manual_revised22nov11

8/2/2019 Microprocessor Sys Lab Manual_Revised22NOV11

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NUST School of Electrical Engineering &

Computer ScienceDepartment of Electrical Engineering

Lab ManualMicroprocessor Based Systems

Prepared by:

Asst Prof Kamran Zaidi

National University of Sciences & Technology (NUST),

Pakistan


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Microprocessor Based Systems Lab Manual 1

LAB No.1

Objective: The aim of the first lab is familiarization with MASM and writing and testing

our first program in Assembly Language.

INTRODUCTION TO MASM

The Microsoft Macro Assembler (MASM) is an x86 assembler for Microsoft Windows

that uses the Intel syntax. Assembly language is a great tool to understand how a

computer works and with the help of MASM you will be able to assemble and run your

programs written in Assembly language.

Writing Assembly Language Programs:

You can write Assembly language programs in any text editor e.g. Notepad etc.

However, you have to make sure that you save your programs with an extension of asmi.e. if you name your file example then it should be saved by going to saveAs and then

typing example.asm in the file name and selecting All Files in the file Type.

Once you have installed MASM on your PC and written your program then you have to

assemble and link your programs before they can be executed.

Assemble Link Execute Cycle:

The process of editing, assembling, linking, and executing assembly language programs

is summarized in Figure below. Following is a detailed description of each step.Step 1: A programmer uses a text editor to create an ASCII text file named the source

file.

Step 2: The assembler (file ML.exe)reads the source file and produces an object file, amachine-language translation of the program. Optionally, it produces a listing file. If any

errors occur, the programmer must return to Step 1 and fix the program.

Step 3: The linker (file Link32.exe) reads the object file and checks to see if the programcontains any calls to procedures in a link library. The linker copies any required

procedures from the link library, combines them with the object file, and produces the

executable file. Optionally, the linker can produce a map file.

Step 4: The operating system loader utility reads the executable file into memory and

branches the CPU to the programs starting address, and the program begins to execute.


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At the end the useful files generated are as follows:

Example.obj

Example.lst

Example.exe

Example.exe is the executable file that can now be run by typing example on the DOSprompt and pressing enter.

First Assembly Language Program:

TITLE Add two registers (example.asm)

; The comments are given after the semi colon on a line

; This program adds 32-bit unsigned

; integers and stores the sum in the ecx register

Include irvine32.inc.data

;variable declarations go here

.codeMain Proc

;instructions go here

Mov eax, 30 ;Assembly Language is NOT case sensitive

Mov ebx, 20Add ecx, eax

Add ecx, ebx

Call dumpregs ;displays the result on the screen by displaying all register values

Exit

Main endp

End main

CPU REGISTERS:Registers are special memory locations on the CPU. One important difference between

older and later processors is that the pre-386 processors are 16-bit instead of 32-bit.There are 8 32-bit general purpose registers. The first 4, eax, ebx, ecx, and edx can also


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be accessed using 16 or 8-bit names. ax gets the first 16 bits of eax, al gets the first 8

bits, and ah gets bits 9-16. The fig below shows all the general purpose and specialpurpose registers and their sizes.


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Lab No.2

Objective: The aim of this lab is to declare and manipulate variables in our assembly

language program and check the output.

ProgramTITLE Add and Subtract, (AddSub2.asm)

; This program adds and subtracts 32-bit unsigned

; integers and stores the sum in a variable.

INCLUDE Irvine32.inc

.dataval1 DWORD 10000h ;val1 declared as a variable of type DWORD and initialized

val2 DWORD 40000h

val3 DWORD 20000hfinalVal DWORD ?

.code

main PROC

mov eax,val1 ; start with 10000h

add eax,val2 ; add 40000hsub eax,val3 ; subtract 20000h

mov finalVal,eax ; store the result (30000h)

call DumpRegs ; display the registers

exit

main ENDPEND main


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Lab No.3

Objective: The aim of this lab is to test and observe the result of different addressingmode instructions.

Use the call dumpregs function to check the values of the registers after each instruction

given below. Also, identify the addressing mode being used.

.data

Val1 WORD 100H

Val2 WORD 200HarrayB BYTE 10H, 20H, 30H, 40H

arrayW WORD 100h, 200h, 300h, 400h

arrayD DWORD 10000H, 20000H

.codeMain Proc

Mov ax, val1

call dumpregs

Mov bx, val2

Mov cl, arrayB

Mov cl, [arrayB+1]

Mov cl, [arrayB+2]

Mov ax, arrayW

Mov ax, [arrayW+2]

Mov bx, [arrayW+4]

Mov ecx, arrayD

Mov ecx, [arrayD+4]

Exit

Main endp

End main


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Lab No. 4

Objective: The aim of this lab is to test and observe the result of different addressingmode instructions.

Use the following instructions in your program and check the register values after each

set of instructions by using the call dumpregs function. Also, identify the type of

addressing mode used.

.data

Array1 BYTE 10H, 20H, 30H, 40H, 50HArray2 WORD 100h, 200h, 300h, 400h, 500h, 600h

Array3 DWORD 10000H, 20000H, 30000H

.code

Main ProcMov esi, OFFSET Array1

Mov edi, OFFSET Array2

Mov edx, OFFSET Array3

Mov al, [esi]

call dumpregs

add esi, 1

Mov al, [esi]

Mov bx, [esi]

Mov cx, [edi]

Add edi, 4Mov cx, [edi]

Mov eax, [edx]

Exit

Main endp

End main


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Lab No. 5

Objective: The aim of this lab is to check the effect of arithmetic instruction on the flags

of the CPU.

Use the following instructions in your program and check the register values after each

set of instructions by using the call dumpregs function.

Mov cx, 1

Sub cx, 1

Mov ax, 0FFFFH

Inc axInc ax

Mov ax, 0FFFFH

Add ax, 1

Mov al, 1Sub al, 2

Mov al, +127

Add al, 1

Mov al, -128

Sub al, 1


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Lab No. 6

Objective: The aim of this lab is to test the students ability to write an Assemblylanguage program independently.

Program:Write a program that asks the user to input 10 integers and stores it in an array of type

WORD. It then prints all the integers on the screen in different colors.


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Lab No. 7

Objective: The aim of this lab is to test the students ability to write an Assemblylanguage program independently.

Program:Write a program that asks the user to input his first and last name and stores it an array of

type String. It then counts the number of characters in the name and displays the result on

the screen.


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Lab No. 8

INTRODUCTION TO MICROCONTROLLERS

Objective: The aim of this lab is to introduce the student to 89C51 microcontroller. Its

architecture and its programming.

What is a Microcontroller?

A MicroController Unit (or MCU) is a computer-on-a-chip. It is a type of

microprocessor emphasizing self-sufficiency and cost-effectiveness, in contrast to a

general-purpose microprocessor (the kind used in a PC). The microcontroller is an IC that

has its own CPU, RAM and non-volatile memory (ROM, EPROM, FLASH EPROM) on

the same chip. Integrating the memory and other peripherals on a single chip and testing

them as a unit increases the cost of that chip, but often results in decreased net cost of the

embedded system as a whole. As a result of this integration, the MCU can perform stand-

alone functions in a variety of embedded systems applications.

Applications:

The microcontroller, nowadays, is an indispensable device for electrical/electronic

engineers because of its versatility and its enormous application. Among the applications

of a microcontroller we can mention industrial automation, mobile telephones, radios,

microwave ovens and VCRs. Besides, the present trend in digital electronics is toward

restricting to microcontrollers and chips that concentrate a great quantity of logical

circuits, like PLDs (Programmable Logic Devices) and GALs (Gate Array Logic). In

dedicated systems, the microcontroller is the best solution, because it is cheap and easy to

manage.

The 8051 Microcontroller:

The Intel 8051 is a Harvard architecture single chip microcontroller (C) which was

developed by Intel in 1980 for use in embedded systems. It was extremely popular in the

1980s and early 1990s, but today it has largely been superseded by a vast range of

enhanced devices with 8051-compatible processor cores that are manufactured by more


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Three-Level Program Memory Lock

128 x 8-Bit Internal RAM 32 Programmable I/O Lines

Two 16-Bit Timer/Counters Six Interrupt Sources

Programmable Serial Channel

Low Power Idle and Power Down Modes

PIN CONFIGURATION:

PIN DESCRIPTION:

VCC

Supply voltage.

GND

Ground.

Port 0

Port 0 is an 8-bit open drain bidirectional I/O port. As an output port each pin can sink

eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as

highimpedance inputs. Port 0 may also be configured to be the multiplexed loworder

address/data bus during accesses to external program and data memory. In this mode P0


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has internal pullups. Port 0 also receives the code bytes during Flash programming, and

outputs the code bytes during program verification.

External pullups are required during program verification.

Port 1

Port 1 is an 8-bit bidirectional I/O port with internal pullups. The Port 1 output buffers

can sink/source four TTL inputs. When 1s are written to Port 1 pins they are pulled high

by the internal pullups and can be used as inputs. As inputs, Port 1 pins that are externally

being pulled low will source current (IIL) because of the internal pullups. Port 1 also

receives the low-order address bytes during Flash programming and verification.

Port 2




being pulled low will source current (IIL) because of the internal pullups. Port 2 emits the

high-order address byte during fetches from external program memory and during

accesses to external data memory that use 16-bit addresses (MOVX @ DPTR). In this

application it uses strong internal pullups when emitting 1s. During accesses to external

data memory that use 8-bit addresses (MOVX @RI), Port 2 emits the contents of the P2

Special Function Register. Port 2 also receives the high-order address bits and some

control signals during Flash programming and verification.

Port 3




being pulled low will source current (IIL) because of the pullups.

OSCILLATOR CHARACTERISTICS:


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XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier

which can be configured for use as an on-chip oscillator, as shown in Figure 1. Either a

quartz crystal or ceramic resonator may be used. To drive the device from an external

clock source, XTAL2 should be left unconnected while XTAL1 is driven as shown in

Figure 2. There are no requirements on the duty cycle of the external clock signal, since

the input to the internal clocking circuitry is through a divide-by-two flip-flop, but

minimum and maximum voltage high and low time specifications must be observed.


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LAB No.9

Write a Program that turns on an LED (connected to Pin P1.1) on the Trainer based on

whether a switch (connected to Pin P1.2) is ON or OFF.

ASSEMBLY LANGUAGE PROGRAM:

TITLE EX1.A51

ORG 0H ; Starting address of the ROM

SJMP START ; Jump to the beginning of the program

ORG 40H ; First address above the Interrupt VectorSTART: ; Start Label

CLR P1.1 ; Turn off the LED to start with

HERE:

JNB P1.2, HERE ; If the Switch is off then wait here

SETB P1.1 ; Turn on the LED

WAIT:

JB P1.2, WAIT

SJMP START

END ; End of Program

#include //header file for 89C51

#include

sbit DIPswitch = P1^2; // DIP switch input on Port 1 bit 4

sbit redLED = P1^1; // green LED output on Port 1 bit 5

void main(){

//main function starts

while(1){

redLED = 0;

while (DIPswitch == 0)

{ }

redLED = 1;

while (DIPswitch == 1)

{ }

}

}


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LAB NO.10

Write a Program that generates a square wave pulse on one of its pins (P1.1)


TITLE EX2.A51



ORG 30H ; First address above the Interrupt Vector

START: ; Start Label

AGAIN:

CLR P1.1 ; Clears the pin P1.1

SETB P1.1 ; Sets pin P1.1

JMP AGAIN ; Unconditional Jump to label AGAIN


EXERCISE:

Q1. Can you find a single instruction from the instruction set that will alone perform

the function of clearing (CLR) and setting (SETB) a pin. Modify the code above so that

the waveform is generated using this instruction.

Q2. What is the Time Period and Frequency of the waveform generated?

Q3. Change the code above so that the Time Period of the wave is now doubled

Q4. Check whether the high time and low time of the pulse are equal? If not why not?


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LAB No.11

Write a program that uses the Timer0 of the 89C51 to generate a pulse of 10KHz

frequency on P1.0 using an Oscilloscope.


TITLE EX3.A51



ORG 30H ; First address above the Interrupt Vector

START: ; Start Label

MOV TMOD, #02H ; 8-bit auto reload mode

MOV TH0, #-50 ; -50 reload value in TH0

SETB TR0 ; Start the Timer0

LOOP:

JNB TF0, LOOP ; Wait for timer to overflow

CLR TF0 ; Clear the Overflow Flag

CPL P1.0 ; Toggle port bit

SJMP LOOP ; Repeat the loop



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LAB No. 13

Objective:

To understand and use the Interrupts of the 89C51

Lab:

Write and burn the controller with a program that waits for a button to be pressed to turn

on an LED connected to its port pin P1.0. The microcontroller detects this button press on

its EXT0 pin. Once the button is pressed and released the LED should remain ON. At this

stage the LED should turn OFF if the button is pressed again.


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LAB No. 14

Objective:

To understand the 89C51 Interrupts.

Lab:

Write a program that uses two Ports as 7-segment digit Outputs (Port1 as LSD and Port2

as MSD). One Input SHOW at Port 0.0 which is a latched type switch. The other input

DOOR at P3.2 (External Interrupt0) is a miniature switch attached with a door. Each time

the door is opened the switch DOOR is pressed and causes the software to execute

Interrupt Service Routine where the number of Door open is counted. When the input

switch SHOW is pressed, the number of Door open Count is displayed on the 7-SegmentLED display.

Writing the Program:

1. Declare the inputs and outputs.2. Initialize the IE (Interrupt Enable Register) according to the Interrupt enabling

order.

IE.7= Global Enable/Disable,

IE.6= Undefined,IE.5= Timer2 Interrupt,

IE.4 = Serial port Interrupt,

IE.3 = Timer1 Interrupt,

IE.2 = External Interrupt1,

IE.1 = Timer0 Interrupt,IE.0 = External Interrupt 0.

3. Set the IT0 bit (TCON.0) to declare the External Interrupt0 as Falling Edge

triggered. (IT0=0 for low level activated interrupt).

Seven Segment Display:

a

b

c

d

e

f

g


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LAB No. 15

Objective:

To understand the Serial Port Transmit operation of the 89C51.

Lab:

Write a Sub Routine OUTCHAR to transmit the 7-bit ASCII code in the Accumulator out

the 8951 serial port with odd parity added as the 8th

bit.

ASSEMBLY LANGUAGE PROGRAM (SUB ROUTINE):

OUTCHAR:MOV C, P ; Put parity bit in Carry flag

CPL C ; Change to odd parity

MOV ACC, C ; Add to Character code

AGAIN:

JNB TI, AGAIN ; Check to see if TI empty, if not then again

CLR TI ; YES, Clear flag

MOV SBUF, ACC ; Send Character

CLR ACC.7 ; Strip off parity bit

MOV SBUF, A

CLR ACC.7

RET

EXERCISE:

Q. Use the Sub-Routine given above in your program so that all the characters from

A to Z are transmitted to the PC by serial Port and printed on the screen. For this you will

have to use Hyper Terminal Utility in Windows.


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microprocessor sys lab manual_revised22nov11

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