DON\'T COPY PREVIOUS ANSWERS BECAUSE THEY\'RE NOT WORKING Write the equivalent i

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DON'T COPY PREVIOUS ANSWERS BECAUSE THEY'RE NOT WORKING

Write the equivalent instructions for the rep cmpsb and rep scasb below. This must be in inline assembly for credit.

        // cmpsb example: find a character in a string
        lea edi,s2            // move the address of source into the esi register
        mov ecx,length s2   // move the length of the source string into ecx (counter)
        cld                    // set the direction flag to UP
        mov eax,'b'            // set up the eax register for the compare
repne    scasb                // compare the al register to the value at [edi] and repeat while not
                            //     until ecx = 0
        je equal            // jump if character found, i.e. al was equal to [edi]
        nop                    // if we go here the strings are NOT equal
equal:    nop                    // nop: doesn't do anything but waste time
        
        // cmpsb example: compare two strings
        lea esi,s1            // move the address of source into the esi register
        lea edi,s2            // move the address of dest into the edi register
        mov ecx,length s1    // move the length of the source string into ecx (counter)
        cld                        // set the direction flag to UP
repe    cmpsb
        jne    notequ        // jump if strings not equal
        nop                // if we go here the strings are equal
notequ:    nop       

   Copy and paste all your lines of code, including the C code into Blackboard. If I copy your code into visual studio, it should execute without modification. Do not attach a file.

   Be sure to comment every line for credit.

Explanation / Answer

1: find a character in a string taken as an array

cr equ 13

lf equ 10

data segment

prompt1 db cr,lf,'enter any string :',0

promp2 db cr,lf,'enter any character :',0

promp3 db cr,lf,0

promp4 db 10,13,'character not found in the given string'

promp5 db ' character(s) found in the given string '

char db ?

count db 0

parameter1 label byte

m1 db 0ffh

l db ? ;uninitialised

p11 db 0ffh dup ('$')

data ends

output macro msg ;used for display on screen similar to printf in c language

mov ah,9

lea dx,msg

int 21h

endm

code segment

assume cs:code,ds:data

start:

mov ax,data

mov ds,ax

output prompt1

lea dx,parameter1

mov ah,0ah

int 21h

output promp2

mov ah,1

int 21h

mov char,al

output promp3

lea si,p11

mov cl,l

mov ch,0

check:

mov al,[si]

cmp char,al

jne next

inc count

next:

inc si

loop check

cmp count,0

je notfound

output promp3

mov dl,count

add dl,30h

mov ah,2

int 21h

output promp5

jmp exit

notfound:

output promp4

exit:   mov ah,4ch

int 21h

code ends

end start

2.Compare two strings

Str1 dw 40 dup(?)

Output:enter first string

inputs str1,40

Output:enter second string

inputs str2,40

lea si,str1

lea di,str2

cld

repe cmpsw

jz label1

strings nt equal

jmp quit

label1: strings equal

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