附录1元器件清单
元件名称 AT89C52 74LS22 LM324 电阻 排阻 液晶显示屏 滑动变阻器 晶振
数量 1 1 1 3 1 1 1 1 备注 10k 4.7K LCD1602 10K 12MHZ 21
附录2 程序清单
#include
#define uchar unsigned char #define uint unsigned int
//#define Fosc 24000000/12000000 //12分频后的频率
#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 //uint T_temp;
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[4]={10,50,200,10}; //三种波的频率单位 sawtooth
uchar idata wavefreq[4]={1,1,1,1}; //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[]={\Wave \\Wave \\Wave \ \ \
uchar idata lcd_hang2[16]={\ Hz \
/*uchar code wave_freq_adjust[]={ //频率调整中间值
0xff,0xb8,0x76,0x56,0x43,0x37,0x2e,0x26,0x20,0x1c, //正弦波频率调整中间值
0xff,0x8e,0x5a,0x41,0x32,0x28,0x20,0x1b,0x17,0x0e, //三角波频率调整中间值 0xff,0x8e,0x5a,0x41,0x32,0x28,0x20,0x1b,0x17,0x0e}; uint code wave_freq_adjust[]={ //频率调整中间值 380,184,118,86,67,55,46,28,38,32, 295,142, 90,65,50,40,32,27,23,14,
295,142, 90,65,50,40,32,27,23,14}; */
/*uchar code waveTH[]={
0xfc,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff, 0xfc,0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff, 0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff}; uchar code waveTL[]={
0xf2,0x78,0xfb,0x3c,0x63,0x7d,0x8f,0x9d,0xa8,0xb1, 0x17,0x0b,0xb2,0x05,0x37,0x58,0x70,0x82,0x90,0x9b,
0x4d,0xa7,0xc4,0xd3,0xdc,0xe2,0xe6,0xea,0xec,0xee};*/
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/***********这两组数组很重要，需要根据波形来调试，选择合适的值，使输出波形达到频率要求************/
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,
//输出电压从0到最小值（正弦波1/4部分）
0x80,0x7c,0x79,0x76,0x72,0x6f,0x6c,0x69,0x66,0x63,0x60,0x5d,0x5a,0x57,0x55,0x51,0x4e,0x4c,0x48,0x45,0x43,
0x40,0x3d,0x3a,0x38,0x35,0x33,0x30,0x2e,0x2b,0x29,0x27,0x25,0x22,0x20,0x1e,0
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x1c,0x1a,0x18,0x16 ,0x15,0x13,
0x11,0x10,0x0e,0x0d,0x0b,0x0a,0x09,0x08,0x07,0x06,0x05,0x04,0x03,0x02,0x02,0x01,0x00,0x00,0x00,0x00,0x00,0x00,
//输出电压从最小值到0（正弦波1/4部分）
0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x02 ,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0a,0x0b,0x0d,0x0e,0x10,
0x11,0x13,0x15 ,0x16,0x18,0x1a,0x1c,0x1e,0x20,0x22,0x25,0x27,0x29,0x2b,0x2e,0x30,0x33,0x35,0x38,0x3a,0x3d,
0x40,0x43,0x45,0x48,0x4c,0x4e,0x51,0x55,0x57,0x5a,0x5d,0x60,0x63,0x66 ,0x69,0x6c,0x6f,0x72,0x76,0x79,0x7c,0x80};
uchar code sawtooth_tab[]={
0x00,0x02,0x04,0x06,0x08,0x0a,0x0c,0x0e,0x10,0x12,0x14,0x16,0x18,0x1a,0x1c,0x1e,0x20,0x22,0x24,0x26,0x28,0x2a,0x2c,0x2e,
0x30,0x32,0x34,0x36,0x38,0x3a,0x3c,0x3e,0x40,0x42,0x44,0x46,0x48,0x4a,0x4c,0x4e,0x50,0x52,0x54,0x56,0x58,0x5a,0x5c,0x5e,
0x60,0x62,0x64,0x66,0x68,0x6a,0x6c,0x6e,0x70,0x72,0x74,0x76,0x78,0x7a,0x7c,0x7e,0x80,0x82,0x84,0x86,0x88,0x8a,0x8c,0x8e};
// 0x90,0x92,0x94,0x96,0x98,0x9a,0x9c,0x9e,0xa0,0xa2,0xa4,0xa6,0xa8,0xaa,0xac,0xae,0xb0,0xb2,0xb4,0xb6,0xb8,0xba,0xbc,0xbe,
// 0xc0,0xc2,0xc4,0xc6,0xc8,0xca,0xcc,0xce,0xd0,0xd2,0xd4,0xd6,0xd8,0xda,0xdc,0xde,0xe0,0xe2,0xe4,0xe6,0xe8,0xea,0xec,0xee};
void delay(uchar z) {
uint x,y; for(x=z;x>0;x--) for(y=110;y>0;y--); }
void triangle_out() //三角波输出 {
DAdata=triangle_tab[wavecount++]; if(wavecount>64) wavecount=0; DA_S1=0; //打开8位输入寄存器 DA_S1=1; //关闭8位输入寄存器 }
void sine_out() //正弦波输出 {
DAdata=sine_tab[wavecount++]; DA_S1=0; //打开8位输入寄存器 DA_S1=1; //关闭8位输入寄存器
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}
void square_out() //方波输出 {
judge=~judge;
if(judge==1) DAdata=0xff; else DAdata=0x00;
DA_S1=0; //打开8位输入寄存器 DA_S1=1; //关闭8位输入寄存器 }
void sawtooth_out() //锯齿波输出 {
DAdata=sawtooth_tab[wavecount++]; if(wavecount>71) wavecount=0; DA_S1=0; //打开8位输入寄存器 DA_S1=1; //关闭8位输入寄存器 }
/************1602液晶的相关函数*************/ #define lcd_ports P1 sbit rs=P2^2; sbit rw=P2^3; sbit lcden=P2^4;
void write_com(uchar com) {
rs=0; //置零，表示写指令 lcden=0;
lcd_ports=com; delay(5); lcden=1; delay(5); lcden=0; }
void write_date(uchar date) {
rs=1; //置1，表示写数据（在指令所指的地方写数据） lcden=0;
lcd_ports=date; delay(5); lcden=1; delay(5); lcden=0; }
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