实验一:
(1)
assume ds:data, cs:code, ss:stack data segment db 16 dup(0) data ends stack segment db 16 dup(0) stack ends code segment start: mov ax, data mov ds, ax mov ax, stack mov ss, ax mov sp, 16 mov ah, 4ch int 21h code ends end start
cs:076c ds: 076a ss:076b
data段的段地址是X-2, stack的段地址是X-1
(2)
assume ds:data, cs:code, ss:stack data segment db 4 dup(0) data ends stack segment db 8 dup(0) stack ends code segment start: mov ax, data mov ds, ax mov ax, stack mov ss, ax mov sp, 8 mov ah, 4ch int 21h code ends end start
cs:076c ds: 076a ss:076b
data段的段地址是X-2, stack的段地址是X-1
(3)
assume ds:data, cs:code, ss:stack data segment db 20 dup(0) data ends stack segment db 20 dup(0) stack ends code segment start: mov ax, data mov ds, ax mov ax, stack mov ss, ax mov sp, 20 mov ah, 4ch int 21h code ends end start
cs:076e ds: 076a ss:076c
data段的段地址是X-4, stack的段地址是X-2
(4)
assume ds:data, cs:code, ss:stack code segment start: mov ax, data mov ds, ax mov ax, stack mov ss, ax mov sp, 20 mov ah, 4ch int 21h code ends data segment db 20 dup(0) data ends stack segment db 20 dup(0) stack ends end start
cs:076a ds: 076c ss:076e
data段的段地址是X+2, stack的段地址是X+4
(5)
1)实际分配的内存为((N/16+1)*16
2)task1_4.asm仍然可以执行;因为“end start”改为“end”,则程序不能识别 start,会从程序开头,数据段和栈段开始执行,不是从程序代码开始,数据段和栈段所代表的代码则是乱码
实验二:
assume cs:code code segment mov ax, 0b800h mov ds, ax mov bx, 0f00h mov ax, 0403h mov cx, 160 s: mov [bx], ax add bx, 2 loop s mov ah, 4ch int 21h code ends end
结果:
实验三:
assume cs:code data1 segment db 50, 48, 50, 50, 0, 48, 49, 0, 48, 49 ; ten numbers data1 ends data2 segment db 0, 0, 0, 0, 47, 0, 0, 47, 0, 0 ; ten numbers data2 ends data3 segment db 16 dup(0) data3 ends code segment start: mov bx,0 ; mov dx,0 ; mov cx,10 ; s: mov dx,0 mov ax,data1 mov ds,ax add dl,[bx] mov ax,data2 mov ds,ax add dl,[bx] mov ax,data3 mov ds,ax mov [bx],dl inc bx loop s code ends end start
相加前
data1:
data2:
data3:
反汇编:
结果:
实验四:
assume cs:code data1 segment dw 2, 0, 4, 9, 2, 0, 1, 9 data1 ends data2 segment dw 8 dup(?) data2 ends code segment start: mov ax,data1 mov ds,ax mov ax,data2 mov ss,ax mov sp,16 mov bx,0 mov cx,8 s: push ds:[bx] add bx,2 loop s mov ah, 4ch int 21h code ends end start
在076A:0010处显示的是data2中的内容
实验五:
运行结果:
assume cs:code, ds:data data segment db 'Nuist' db 2, 3, 4, 5, 6 data ends code segment start: mov ax, data mov ds, ax mov ax, 0b800H mov es, ax mov cx, 5 mov si, 0 mov di, 0f00h s: mov al, [si] and al, 0dfh mov es:[di], al mov al, [5+si] mov es:[di+1], al inc si add di, 2 loop s mov ah, 4ch int 21h code ends end start
(2)
(3)line25执行之后、line27执行之前,观察 结果:
(4)源代码中line19的作用是:把单片机的AL与DF(1101 1111)进行与,就是把左边数过去的第三位清0
(5)line4中的字节数据,用于控制5个字符每个字符的颜色
实验六:
assume cs:code, ds:data data segment db 'Pink Floyd ' db 'JOAN Baez ' db 'NEIL Young ' db 'Joan Lennon ' data ends code segment start: mov ax, data mov ds, ax mov bx, 0 mov cx, 5 s: mov al, [bx] or al, 00100000B mov [bx], al add bx, 16 loop s mov ah, 4ch int 21h code ends end start
调试:
反汇编:
结果:
实验七:
assume cs:code, ds:data, es:table data segment db '1975', '1976', '1977', '1978', '1979' dw 16, 22, 382, 1356, 2390 dw 3, 7, 9, 13, 28 data ends table segment db 5 dup( 16 dup(' ') ) ; table ends code segment start: mov ax,data mov ds, ax mov ax,table mov es, ax mov si,0 mov di,0 mov cx,5 s: mov ax,ds:[si] mov es:[di], ax mov ax,ds:[si+2] mov es:[di+2], ax mov ax,ds:[si+84] mov es:[di+5],ax mov dx,ds:[si+84+2] mov es:[di+7],dx push cx mov cx,ds:[84+84+bx] mov es:[di+0ah],cx div cx pop cx mov es:[di+0dh],ax add si,4 add bx,2 add di,16 loop s mov ah, 4ch int 21h code ends end start
table原始数据:
运行完后: