标签:add 9.png 找不到 实验 png size class 查看 sum
1.
源码:
assume cs:code, ds:data, ss:stack data segment dw 0123h, 0456h, 0789h, 0abch, 0defh, 0fedh, 0cbah, 0987h data ends stack segment dw 0, 0, 0, 0, 0, 0, 0, 0 stack ends code segment start: mov ax,stack mov ss, ax mov sp,16 mov ax, data mov ds, ax push ds:[0] push ds:[2] pop ds:[2] pop ds:[0] mov ax,4c00h int 21h code ends end start
运行结果:
code段地址为076b,而stack段地址比它小一位。查看后,data段数据为0123h 0456h 0789h 0ABCh-0DEFh 0FEDh 0CBAh 0987h
程序返回前,cs=076C,ss=076a,ds=076b。
code段地址为X,data段地址为X-2,stack段地址为X-1。
2.
源码:
assume cs:code, ds:data, ss:stack data segment dw 0123h, 0456h data ends stack segment dw 0, 0 stack ends code segment start: mov ax,stack mov ss, ax mov sp,16 mov ax, data mov ds, ax push ds:[0] push ds:[2] pop ds:[2] pop ds:[0] mov ax,4c00h int 21h code ends end start
data段中数据为:0123h 0456h
cs=076c,ss=076b,ds=076a
code段地址为X,data段地址为X-2,stack段地址为X-1。
对于:
name segment
...
name ends
段中数据占N个字节,则程序加载后该段实际占据空间为[(N+15)/16]*16。
3.
assume cs:code, ds:data, ss:stack code segment start: mov ax,stack mov ss, ax mov sp,16 mov ax, data mov ds, ax push ds:[0] push ds:[2] pop ds:[2] pop ds:[0] mov ax,4c00h int 21h code ends data segment dw 0123h, 0456h data ends stack segment dw 0,0 stack ends end start
data段数据为0123h 0456h
cs=076a,ds=076d,ss=076e
若code段地址为X,则data段地址为X+3,stack段地址为X+4
4.
实验3能正常执行。因为前两个是数据段开头,而第三个是以指令开头,去掉start后,前两个就找不到入口了。
5.
assume cs:code a1 segment db 1,2,3,4,5,6,7,8 a1 ends b1 segment db 1,2,3,4,5,6,7,8 b1 ends c1 segment db 0,0,0,0,0,0,0,0 c1 ends code segment start: mov bx,0 mov dx,0 mov cx,8 s: mov dx,0 mov ax,a1 mov ds,ax add d1,[bx] mov ax,c1 mov ds,ax mov [bx],dl inc bx loop s mov ax,4c00h int 21h code ends end start
数据段c在程序运行前后如图。
6.
assume cs:code a segment dw 1,2,3,4,5,6,7,8,9,0ah,0bh,0ch,0dh,0eh,0fh,0ffh a ends b segment dw 0,0,0,0,0,0,0,0 b ends code segment start: mov ax,a mov ds,ax mov ax,b mov ss,ax mov sp,10h mov bx,0 mov cx,8 s: push [bx] inc bx inc bx loop s mov ax,4c00h int 21h code ends end start
总结:
通过这6个实验的学习,我对code,stack,data等段有了深入的了解。
标签:add 9.png 找不到 实验 png size class 查看 sum
原文地址:https://www.cnblogs.com/1193093174qq/p/10015641.html