This document contains 5 assembly language programs written for the EMU8086 simulator:
1) A "Hello World" program that displays a message in Spanish.
2) A program that displays a student's name, university, date, and course.
3) A program that compares 2 numbers from 0 to 9.
4) A program that sums the values in a 10-element vector and displays the result.
5) A program that converts values between binary, decimal, and hexadecimal.
4. EMU8086
Posee una interfaz de usuario muy amistosa que permite familiarizarse con los fundamentos
de la programación en lenguaje ensamblador(assembler) de forma muy intuitiva, aparte de
eso brinda una serie de recursos para ejecutar y depurar los programas. También tiene algunas
desventajas como el de no soportar algunas de las interrupciones más interesantes que posee
el sistema operativo y tampoco puede acceder a los puertos físicos (reales), sino que los emula
usando otros programas que ya están incluidos en su respectiva carpeta.
http://assembler8086.blogspot.com/2012/10/ejercicios-en-emu-8086.html
Comprobada la forma de ejecución realizar los siguientes programas en base a los códigos
expuestos como ejemplos.
• Ejecutar el programa hola mundo, y debe cambiar los mensajes de pantalla al español.
Compilar un programa en EMU8086 que indique lo siguiente:
5.
6.
7. Compilar un programa en EMU8086 que indique lo siguiente: Nombre completo del
estudiante, Universidad, Fecha y materia
name "hi-world"
; this example prints out "hello world!"
; by writing directly to video memory.
; in vga memory: first byte is ascii character, byte that follows is character attribute.
; if you change the second byte, you can change the color of
; the character even after it is printed.
; character attribute is 8 bit value,
; high 4 bits set background color and low 4 bits set foreground color.
; hex bin color
;
; 0 0000 black
; 1 0001 blue
; 2 0010 green
; 3 0011 cyan
; 4 0100 red
; 5 0101 magenta
; 6 0110 brown
; 7 0111 light gray
; 8 1000 dark gray
; 9 1001 light blue
; a 1010 light green
; b 1011 light cyan
; c 1100 light red
; d 1101 light magenta
; e 1110 yellow
; f 1111 white
8. org 100h
; set video mode
mov ax, 3 ; text mode 80x25, 16 colors, 8 pages (ah=0, al=3)
int 10h ; do it!
; cancel blinking and enable all 16 colors:
mov ax, 1003h
mov bx, 0
int 10h
; set segment register:
mov ax, 0b800h
mov ds, ax
; print "hello world"
; first byte is ascii code, second byte is color code.
mov [02h], 'D'
mov [04h], 'i'
mov [06h], 'e'
mov [08h], 'g'
mov [0ah], 'o'
11. mov [52h], 'd'
mov [54h], 'o'
mov [56h], 'r'
mov [58h], 'e'
mov [5ah], 's'
; color all characters:
mov cx, 12 ; number of characters.
mov di, 03h ; start from byte after 'h'
c: mov [di], 11101100b ; light red(1100) on yellow(1110)
add di, 2 ; skip over next ascii code in vga memory.
loop c
; wait for any key press:
mov ah, 0
int 16h
ret
12. Compilar un programa que permita comparar 2 números del 0 al 9.
name "flags"
org 100h
; this sample shows how cmp instruction sets the flags.
; usually cmp instruction is followed by any relative
; jump instruction such as: je, ja, jl, jae...
; it is recommended to click "flags" and "analyze"
; for better visual expirience before stepping through this code.
; (signed/unsigned)
; 4 is equal to 4
mov ah, 4
mov al, 4
cmp ah, al
nop
; (signed/unsigned)
13. ; 4 is above and greater then 3
mov ah, 4
mov al, 3
cmp ah, al
nop
; -5 = 251 = 0fbh
; (signed)
; 1 is greater then -5
mov ah, 1
mov al, -5
cmp ah, al
nop
; (unsigned)
; 1 is below 251
mov ah, 1
mov al, 251
cmp ah, al
nop
; (signed)
; -3 is less then -2
mov ah, -3
mov al, -2
cmp ah, al
nop
; (signed)
; -2 is greater then -3
14. mov ah, -2
mov al, -3
cmp ah, al
nop
; (unsigned)
; 255 is above 1
mov ah, 255
mov al, 1
cmp ah, al
nop
; now a little game:
game: mov dx, offset msg1
mov ah, 9
int 21h
; read character in al:
mov ah, 1
int 21h
cmp al, '0'
jb stop
cmp al, '9'
ja stop
cmp al, '5'
jb below
ja above
mov dx, offset equal_5
15. jmp print
below: mov dx, offset below_5
jmp print
above: mov dx, offset above_5
print: mov ah, 9
int 21h
jmp game ; loop.
stop: ret ; stop
msg1 db "enter a number or any other character to exit: $"
equal_5 db " is five! (equal)", 0Dh,0Ah, "$"
below_5 db " is below five!" , 0Dh,0Ah, "$"
above_5 db " is above five!" , 0Dh,0Ah, "$"
Compilar un programa que permita sumar 10 valores asignados a un vector.
name "calc-sum"
org 100h ; directive make tiny com file.
16. ; calculate the sum of elements in vector,
; store result in m and print it in binary code.
; number of elements:
mov cx, 10
; al will store the sum:
mov al, 0
; bx is an index:
mov bx, 0
; sum elements:
next: add al, vector[bx]
; next byte:
inc bx
; loop until cx=0:
loop next
; store result in m:
mov m, al
; print result in binary:
mov bl, m
mov cx, 8
print: mov ah, 2 ; print function.
17. mov dl, '0'
test bl, 10000000b ; test first bit.
jz zero
mov dl, '1'
zero: int 21h
shl bl, 1
loop print
; print binary suffix:
mov dl, 'b'
int 21h
mov dl, 0ah ; new line.
int 21h
mov dl, 0dh ; carrige return.
int 21h
; print result in decimal:
mov al, m
call print_al
; wait for any key press:
mov ah, 0
int 16h
18. ret
; variables:
vector db 4, 7, 8, 2, 1, 10, 9, 7, 22, 100
m db 0
print_al proc
cmp al, 0
jne print_al_r
push ax
mov al, '0'
mov ah, 0eh
int 10h
pop ax
ret
print_al_r:
pusha
mov ah, 0
cmp ax, 0
je pn_done
mov dl, 10
div dl
call print_al_r
mov al, ah
add al, 30h
mov ah, 0eh
int 10h
jmp pn_done
pn_done: