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[ilrxx]

我有个同事要考试，有几道题大家帮忙解释下含义，我是搞java的，这貌似是汇编，看不懂。。谢谢了。

实验一 循环程序的调试与运行
一．实验目的	掌握循环程序的调试运行方法
二．实验内容	
1、程序1
data segment
  d1 db 2, -1,-3,5,6,9,18,-29,-72,8,122,-31,95,76,91,-2
  rs db ?
data ends
stack1 segment
  db 100 dup(?)
stack1 ends
code segment
  main proc far
    assume cs:code,ds:data,ss:stack1
  start:    push ds
          sub ax,ax
          push ax
          mov ax,data
          mov ds,ax
          lea bx,d1
          mov cx,16
          mov dl,0
  lop1:   mov al,[bx]
          cmp al,0
          jge jus
          inc dl
  jus:    inc bx
          dec cx
          jnz lop1
          mov rs,dl
          add dl,30h
          mov ah,2
          int 21h
          ret
  main endp
code ends
  end start
2．程序2
data segment
     num dw 6789h
data ends
stack1 segment
     db 100 dup(?)
stack1 ends
code segment
     main proc far
          assume cs:code,ds:data,ss:stack1
     start:push ds
           sub ax,ax
           push ax
           mov ax,data
           mov ds,ax
           mov bx,num
           mov ch,4
     rota:mov cl,4
          rol bx,cl
          mov al,bl
          and al,0fh
          add al,30h
          cmp al,3ah
          jl print
          add al,07h
     print:mov dl,al
           mov ah,2
           int 21h
           dec ch
           jnz rota
           ret
       main endp
    code ends
         end start
实验二 PC串行接口实验
一．实验目的	掌握PC机的基本串行通信
二．实验内容
参考程序
data segment
        flag db 0
        info db 13,10
                db 'please select(s=sending or r=receiving)'
                db '$'
                sendinfo db 13,10
                         db 'sending...'
                         db 13,10
                         db '$'
                receiveinfo db 13,10
                          db 'receiving...'
                          db 13,10
                          db '$'
data ends
stack segment para stack 'stack'
        db 256 dup(0)
stack ends
code segment
        start proc far
                assume cs:code,ds:data
                push ds
                mov ax,0
                push ax
                mov ax,data
                mov ds,ax
                mov al,0h
                out 21h,al
                mov dx,2fbh
                mov al,80h
                out dx,al
                mov dx,2f8h
                mov al,060h
                out dx,al
                mov dx,2f9h
                mov al,0
                out dx,al
                mov dx,2fbh
                mov al,0ah
                out dx,al
                mov dx,2fch
                mov al,0ah
                out dx,al
                mov dx,2fch
                mov al,0bh
                out dx,al
                mov dx,2f9h
                mov al,01h
                out dx,al
                sti
                ;
                push ds
                mov dx,offset irecve
                mov ax,seg irecve
                mov ds,ax
                mov al,0bh
                mov ah,25h
                int 21h
                pop ds
                mov dx,offset info
                mov ah,9
                int 21h
                mov ah,1
                int 21h
                cmp al,'s'
                je sending
                cmp al,'s'
                je sending
                cmp al,'s'
                jne next
        sending:
                call send
                ret
        next:   cmp al,'r'
                je receiving
                cmp al,'r'
                jne quit
        receiving:
                call receive
        quit:   ret
        start endp

receive proc
        mov dx,offset receiveinfo
        mov ah,9
        int 21h
refore:
        cmp flag,'!'
        jz sequit
        jmp refore
requit:ret
receive endp

send proc
        mov dx, offset sendinfo
        mov ah,9
        int 21h
sefore: cmp flag,'!'
jz sequit
mov dx,2fdh
in al,dx
test al,20h
jz sefore
mov ah,0
int 16h
mov flag,al
mov dx,2f8h
out dx,al
mov bx,0
mov ah,14
int 10h
jmp sefore
sequit:ret
send endp

irecve proc
        push ax
        push bx
        push dx
        push ds
        mov dx,2fdh
        in al ,dx
        test al,1eh
        jnz error
        mov dx,2f8h
        in al,dx
        mov flag,al
        and al,7fh
        mov bx,0
        mov ah,14
        int 10h
        jmp exit
error:
        mov dx,2f8h
        in al,dx
        mov al,'?'
        mov bx,0
        mov ah,14
        int 10h
exit:
        mov al,20h
        out 20h,al
        pop ds
        pop dx
        pop bx
        pop ax
        sti
        iret
irecve endp
code ends
        end start

给个运行结果和大概意思就行了