sample.asm

这是汇编程序的四个实验.对课程设计十分有用.是汇编初学者的好的例子.

;PROGRAM TITLE GOES HERE--Compare string
;***********************************************************************************
datarea segment               ;define data segment
 string1  db  'Move the cursor backward.'  
 string2  db  'Move the cursor backward.'
;
 mess1    db  'Match.',13,10,'$'
 mess2    db  'No match!',13,10,'$'
datarea ends
;********************************************************************************
prognam segment        ;define code segment
;________________________________________________________________________
main proc far
     assume cs:prognam,ds:datarea,es:datarea
start:                ;starting execution address
;set up stack for return
     push ds              ;save old data segment
     sub ax,ax              ;put zero in AX
     push ax               ;save it on stack
;set DS register to current data segment
     mov ax,datarea         ;datarea segment addr        
     mov ds,ax             ;into DS register
     mov es,ax             ;into ES register
;MAIN PART OF PROGRAM GOES HERE
     lea si,string1
     lea di,string2
     cld
     mov cx,25
     repz cmpsb
     jz   match
     lea dx,mess2
     jmp short disp
match: 
     lea dx,mess1
disp:
     mov ah,09
     int 21h
     ret      ;return to DOS
main endp   ;end of main part of program
;________________________________________________________________________
prognam ends ;end of code segment
;***************************************************************
end start  ;end assembly