Problem 1
Write a procedure to find the factorial of a number present in cx.
//Code
fact proc mov ax, 1 top1: mul cx loop top1 ret fact endp
Problem 2
String usage (Example listings 11.1, 11.2, 11.3)
//Code .model small .stack 256 .data str db 'Hello', , '$' str2 db 'This is a test$' str3 db 20 dup(0) .code main proc mov ax, @data mov ds, ax mov es, ax lea di, str3 call readstr mov ah, 2 mov dl, 0dh int 21h mov dl, 0ah int 21h lea si, str3 call printstrrev mov ax, 4ch int 21h main endp readstr proc push ax push di cld XOR BX, BX mov ah, 1 int 21h while1: cmp al, 0dh je endwhile1 cmp al, 8h jne else1 dec di dec bx jmp read else1: stosb inc bx read: int 21h jmp while1 endwhile1: pop di pop ax ret readstr endp printstr proc push ax push bx push cx push dx push si mov cx, bx jcxz p_exit cld mov ah, 2 top: lodsb mov dl, al int 21h loop top p_exit: pop si pop dx pop cx pop bx pop ax ret printstr endp printstrrev proc push ax push bx push cx push dx push si mov cx, bx jcxz p_exit2 add si, bx sub si, 1 std mov ah, 2 top2: lodsb mov dl, al int 21h loop top2 p_exit2: pop si pop dx pop cx pop bx pop ax ret printstrrev endp end main
Homework
Chapter 10 Section 10.3
Chapter 9 Problem 9
Chapter 9 Problem 10
Chapter 9 Problem 11
Chapter 9 Problem 12
Chapter 10 Program listing 10.4
