Factorial Assembly

.model small
.stack 100h
.data

    a db 1
    b db 5

.code
main proc
    mov ax, @data
    mov ds, ax

    mov al, a
    mov bl, a

    re:
    mul bl
    add bl, a
    cmp bl, b
    jle re

    mov ah, 2
    mov dl, al
    int 21h


    mov ah, 4ch
    int 21h
  main endp
end main