【资源下载】下载地址如下1533：
https://docs.qq.com/doc/DTlRSd01BZXNpRUxl

前  言

    随着电子测量技术与计算机技术的紧密结合，一种新的信号发生器-----波形发生器应运而生。所谓波形发生器是能够产生大量的标准信号和用户定义信号，并保证高精度、高稳定性、可重复性和易操作性的电子仪器。单片机作为微型计算机的一个重要分支，有着广泛的应用范围。本文介绍的是利用89C51单片机和数模转换器件DAC0832产生所需不同信号的低频信号源，其信号幅度和频率都是可以按要求控制的。本设计核心任务是：以AT89C51为核心，结合D/A转换器和DAC0832等器件，用仿真软件设计硬件电路，用汇编语言编写驱动程序，以实现程序控制产生正弦波、三角波、方波、三种常用低频信号。可以通过按键选择波形和输入任意频率值。

关键词：AT89C51单片机；信号发生器；DAC0832

		 #include<reg52.h>
#define  uchar unsigned char
#define  uint  unsigned int
#define DAdata  P0	//DA数据端口
sbit DA_S1= P2^0;   // 控制DAC0832的8位输入寄存器，仅当都为0时，可以输出数据(处于直通状态)，否则，输出将被锁存
sbit DA_S2= P2^1;   // 控制DAC0832的8位DAC寄存器，仅当都为0时，可以输出数据(处于直通状态)，否则，输出将被锁存
sbit key=   P3^2;
uchar wavecount;    //'抽点'计数
uchar THtemp,TLtemp;//传递频率的中间变量
uchar judge=1;      //在方波输出函数中用于简单判别作用
uchar waveform;	    //当其为0、1、2时，分别代表三种波
uchar code freq_unit[3]={10,50,200}; //三种波的频率单位
uchar idata wavefreq[3]={1,1,1}; 	  //给每种波定义一个数组单元，用于存放单位频率的个数
uchar code  lcd_hang1[]={"Sine Wave       " "Triangle Wave   " "Square Wave     " "Select Wave:    " "press No.1 key! "};
uchar idata lcd_hang2[16]={"f=    Hz        "};
uchar code waveTH[]={
    0xfd,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
0xfd,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
0xec,0xf6,0xf9,0xfb,0xfc,0xfc,0xfd,0xfd,0xfd,0xfe};
uchar code waveTL[]={ 
    0x06,0x8a,0x10,0x4e,0x78,0x93,0xa8,0xb3,0xbe,0xc6, //正弦波频率调整中间值
0xac,0xde,0x48,0x7a,0x99,0xaf,0xbb,0xc8,0xd0,0xde,	//三角波频率调整中间值
0x88,0x50,0x90,0x32,0x34,0xbe,0x4a,0xa3,0xe5,0x2c}; 
/*************************************************************************************************/
uchar code triangle_tab[]={	 //每隔数字8，采取一次
0x00,0x08,0x10,0x18,0x20,0x28,0x30,0x38,0x40,0x48,0x50,0x58,0x60,0x68,0x70,0x78,
0x80,0x88,0x90,0x98,0xa0,0xa8,0xb0,0xb8,0xc0,0xc8,0xd0,0xd8,0xe0,0xe8,0xf0,0xf8,0xff,
0xf8,0xf0,0xe8,0xe0,0xd8,0xd0,0xc8,0xc0,0xb8,0xb0,0xa8,0xa0,0x98,0x90,0x88,0x80,
0x78,0x70,0x68,0x60,0x58,0x50,0x48,0x40,0x38,0x30,0x28,0x20,0x18,0x10,0x08,0x00};
uchar code sine_tab[256]={
//输出电压从0到最大值（正弦波1/4部分）
0x80,0x83,0x86,0x89,0x8d,0x90,0x93,0x96,0x99,0x9c,0x9f,0xa2,0xa5,0xa8,0xab,0xae,0xb1,0xb4,0xb7,0xba,0xbc,
0xbf,0xc2,0xc5,0xc7,0xca,0xcc,0xcf,0xd1,0xd4,0xd6,0xd8,0xda,0xdd,0xdf,0xe1,0xe3,0xe5,0xe7,0xe9,0xea,0xec,
0xee,0xef,0xf1,0xf2,0xf4,0xf5,0xf6,0xf7,0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfd,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,
//输出电压从最大值到0（正弦波1/4部分）
0xff,0xff,0xff,0xff,0xff,0xff,0xfe,0xfd,0xfd,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,0xf6,0xf5,0xf4,0xf2,0xf1,0xef,
0xee,0xec,0xea,0xe9,0xe7,0xe5,0xe3,0xe1,0xde,0xdd,0xda,0xd8,0xd6,0xd4,0xd1,0xcf,0xcc,0xca,0xc7,0xc5,0xc2,
0xbf,0xbc,0xba,0xb7,0xb4,0xb1,0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,0x99 ,0x96,0x93,0x90,0x8d,0x89,0x86,0x83,0x80,