da1.asm

包含串行通行的收发程序、电子钟、AD、DA转换、LED按键显示等的源代码

data segment para 'data'
buf db 100 dup(?)
data ends

SSTACK SEGMENT PARA STACK 'STACK'
     DB 256 DUP(0)
SSTACK ENDS

CODE SEGMENT PARA 'CODE'
     ASSUME CS:CODE,DS:DATA,ES:DATA,SS:SSTACK

MAIN PROC FAR
     MOV AX,DATA
     MOV DS,AX
     MOV ES,AX

      
  
 juchibo:mov bl,0	;显示锯齿波
     mov di,25

       mov si,3		;延时
delay0:mov cx,05h
delay1:loop delay1
       dec si
       jnz delay0

a1: mov dx,290h		;DAC基地址
 mov al,bl
    out dx,al		;往D/A转换器输出数据
    add bl,8		;电压加1/16的Uref

    dec di
    cmp di,0		;25个电压采样点
    jnz a2
    jmp juchibo		;di=0,循环
    

      
 a2:  mov ah,1
   int 16h
   jnz over		;有键按下，结束程序
   jmp a1
   

over:mov ah,4ch
       int 21h
       main endp
       code ends 
        end main