汇编常用子程序

****保存dos断点

 
push ds
sub ax,ax
push ax


****寄存器进栈

pushseg macro 
push ax
push bx
push cx
push dx
push si
push di
endm

****寄存器出栈

popseg macro 
pop di
pop si
pop dx
pop cx
pop bx
pop ax
endm

****DOS中断21H

dos21 macro nh
mov ah,nh
int 21h
endm

****接收字符串

getchar macro inbuf,length                   
        lea dx,inbuf
mov ah,0ah
int 21h
mov cx,length
mov bh,0
mov bl,inbuf+1
sub cx,bx
getchar1:
mov [bx+inbuf+2],20h
inc bx
loop getchar1
getchar endm