1-Hoa thường

org 100h

.model small

.stack 100h

.data

    msg1 db 'Nhap vao mot ki tu inhoa : $'

    msg2 db 10,13,'Khong la ki tu in hoa! Hay nhap lai! :$ '

    msg3 db 10,13,'Ki tu thuong : '

    kytu db ?,'$'

.code

main proc

    mov ax,@data

    mov ds,ax

    mov ah,09h

    lea dx,msg1

    int 21h

nhap:   

    mov ah,01h

    int 21h

    cmp al,'A'    

    jb next       

    cmp al,'Z'

    ja next        

    add al,20h

    mov kytu,al

    mov ah,09h

    lea dx,msg3

    int 21h

    jmp exit

next:

    mov ah,09h

    lea dx,msg2

    int 21h

    jmp nhap

exit:

    mov ah,4ch

    int 21h

main endp

end

ret

2ki tu truoc sau

org 100h

.model small

.stack 100h

.data

    msg1 db 'Nhap vao ki tu :$'

    msg2 db 10,13, 'Ki tu lien truoc ki tu vua nhap :$'

    msg3 db 10,13, 'Ki tu lien sau ki tu vua nhap :$'

    kytu db ?

.code

main proc

    mov ax,@data

    mov ds,ax

    mov ah,09h

    lea dx,msg1

    int 21h

    mov ah,01h

    int 21h

;chuyen ky tu vao bien

    mov kytu,al   

;ky tu dung truoc

    mov ah,09h

    lea dx,msg2

    int 21h

;lay ra ky tu   

    mov dl,kytu

;tang gia tri trong bien 1dv

    add dl,1

;xuat gia tri moi ra man hinh

    mov ah,02h

    int 21h

;ky tu dung sau

    mov ah,09h

    lea dx,msg3

    int 21h

    mov dl,kytu

    add dl,-1

    mov ah,02h

    int 21h

    mov ah,4ch

    int 21h

main endp

end

ret

----------------------------------------------------------

3 nhap xuat chuỗi

org 100h

.model small

.stack 100h

.data

    msg1 db 'Nhap vao 1 chuoi ky tu :$'

    msg2 db 10,13,'Chuoi ky tu vua nhap la :$'

  len    db ?      ;bien

  chuoi  db 101    ;chuoi co nhieu nhat 100 ki tu

  buff   db 102 dup(?)  ;vung nho luu tru ky tu

.code                    

main proc

    mov ax,@data

    mov ds,ax

    mov ah,09h

    lea dx,msg1

    int 21h

    mov ah,0ah ;ham nhap chuoi

    lea dx,chuoi ; dx chua dia chi chuoi

    int 21h

    mov ah,09h

    lea dx,msg2

    int 21h 

    mov si,2    ;vi tri luu ky tu nhap

lap:

    mov dl,chuoi[si]

    cmp dl,13   ;enter -> ket thuc

    je exit

    mov ah,02h

    int 21h

    inc si

    jmp lap  

exit:       

    mov ah,4ch

    int 21h

main endp

end

ret

============================

4. nhập xuất kí tự

; You may customize this and other start-up templates;

; The location of this template is c:\emu8086\inc\0_com_template.txt

org 100h

.model small

.stack 100h

.data

msg1 db 'Nhap 1 ki tu bat ki tu ban phim :$'

msg2 db 10,13,'Ki tu hien thi tren man hinh :$'

.code

main proc

  start:

    mov ax,@data

    mov ds,ax

;in chuoi thong bao    

    mov ah,09h

    lea dx,msg1

    int 21h  

;nhap 1 ki tu tu ban phim   

    mov ah,01h

    int 21h

;luu ki tu vua nhap   

    push ax

    mov ah,09h

    lea dx,msg2

    int 21h 

;lay ki tu vua nhap   

    pop ax

;xuat ki tu   

    mov dl,al

;in ki tu ra man hinh   

    mov ah,02h

    int 21h

  exit: 

    mov ah,21h

    int 21h 

main endp

end

ret

5. thuong – hoa

org 100h

.model small

.stack 100h

.data

    msg1 db 'Nhap vao mot ki tu thuong : $'

    msg2 db 10,13,'Khong la ki tu thuong! Hay nhap lai! : $'

    msg3 db 10,13,'Ki tu hoa : '

    kytu db ?,'$'

.code

main proc

    mov ax,@data

    mov ds,ax

    mov ah,09h

    lea dx,msg1

    int 21h

nhap:   

    mov ah,01h

    int 21h

                  ;kiem tra chu thuong   

    cmp al,'a'     ;so sanh voi a

    jb next        ;nhay neu <a

    cmp al,'z'

    ja next        ;nhay neu >z

    sub al,20h

    mov kytu,al

    mov ah,09h

    lea dx,msg3

    int 21h

    jmp exit

next:

    mov ah,09h

    lea dx,msg2

    int 21h

    jmp nhap

exit:

    mov ah,4ch

    int 21h

main endp

end

ret

======================================

7. x1 x2=

org 100h

.model small

.stack 100h

.data

    msg1 db 'Nhap so nguyen duong x1 : $'

    msg2 db 10,13,'Nhap so nguyen duong x2 : $'

    msg3 db 10,13,'Khong phai so nguyen duong! Hay nhap lai : $'

    msg4 db 10,13,'ket qua phep tinh x1 - 1 :'

    msg5 db 10,13,'ket qua phep tinh x1 + 2 :'

    ;msg6 db 10,13,'ket qua phep tinh x1 - x2 :'

    ;msg7 db 10,13,'ket qua phep tinh x1 + x2 :'

    x1 db ?,'$'

    x2 db ?,'$'

    x3 db ?,'$'

    x4 db ?,'$'

    x5 db ?,'$'

    x6 db ?,'$'

.code

main proc

    mov ax,@data

    mov ds,ax

    mov ah,09h

    lea dx,msg1

    int 21h

    jmp nhapx1

nhapx1:  

    mov ah,01h

    int 21h

    cmp al,'0'    

    jb next1       

    cmp al,'9'

    ja next1

    mov x1,al

    jmp tinhtoan

   ; mov ah,09h

    ;lea dx,msg2

    ;int 21h   

;nhapx2:  

    ;mov ah,01h

    ;int 21h

    ;cmp al,'0'    

    ;jb next2       

    ;cmp al,'9'

    ;ja next2

    ;mov x2,al   

next1:

    mov ah,09h

    lea dx,msg3

    int 21h

    jmp nhapx1

;next2:

   ; mov ah,09h

   ;lea dx,msg3

    ;int 21h

    ;jmp nhapx2

tinhtoan:

    mov ah,09h

    lea dx,msg4

    int 21h

    mov dl,x1

    add x1,2

    mov ah,02h

    int 21h

    mov ah,09h

    lea dx,msg5

    int 21h

    mov dl,x1

    sub x1,1

    mov ah,02h

    int 21h

    mov ah,4ch

    int 21h

main endp

end

ret

8. xuat ra chuoi kit u

org 100h

.model small

.stack 100h

.data

  msg db 'Wellcom to Assembly!$'

.code

main proc

    mov ax,@data

    mov ds,ax

    mov ah,09h

    lea dx,msg

    int 21h

    mov ah,4ch

    int 21h  

main endp

end

ret