;**********************;
;*   數(shù)/模轉(zhuǎn)換實(shí)驗(yàn)2   *;
;*     產(chǎn)生正弦波     *;
;**********************;
data  segment
io0832a        equ 290h      
sin     db 80h,96h,0aeh,0c5h,0d8h,0e9h,0f5h,0fdh
    db 0ffh,0fdh,0f5h,0e9h,0d8h,0c5h,0aeh,96h
    db 80h,66h,4eh,38h,25h,15h,09h,04h
    db 00h,04h,09h,15h,25h,38h,4eh,66h           ;正弦波數(shù)據(jù)
data ends
code segment
   assume cs:code,ds:data
start:  mov ax,data
    mov ds,ax
ll:     mov si,offset sin            ;置正弦波數(shù)據(jù)的偏移地址為SI
    mov bh,32                    ;一組輸出32個(gè)數(shù)據(jù)
lll:    mov al,[si]                  ;將數(shù)據(jù)輸出到D/A轉(zhuǎn)換器
    mov dx,io0832a
    out dx,al
    mov ah,06h
    mov dl,0ffh
    int 21h
    jne exit
    mov cx,1
delay:  loop delay                   ;延時(shí)
    inc si                       ;取下一個(gè)數(shù)據(jù)
    dec bh
    jnz lll                      ;若未取完32個(gè)數(shù)據(jù)則轉(zhuǎn)lll
    jmp  ll
exit:   mov ah,4ch                   ;退出
    int 21h
code ends
   end start