c语言锯齿波函数,锯齿波的函数
基于单片机的波形发生器设计，C语言程序，有个很小的问题，求解决
void juchi() //锯齿波函数
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{ uchar i;
for(i=0;i255;i++)
{DAC0832=i;
dump(10+p);} //延时实现频率可调，p是变量
i=0x00; }
void zhengxian()
{
for(i=0;i256;i++)//i没有声明 上面那个程序都有uchar i; uchar类型的最大值也只有255
{DAC0832=sin[i];//查表取值
dump(2+p);
}
i=0;
}
//最简单的方法就是复制juchi这个函数
//把DAC0832=i;改成DAC832=sin[i];就能看到效果了
void zhengxian() //正弦波函数
{ uchar i;
for(i=0;i255;i++)
{DAC0832=sin[i];
dump(10+p);} //延时实现频率可调，p是变量
i=0x00; }
急求用DAC接口电路，编写产生负向锯齿波、三角波、梯形波的程序
sbit wr=P3^6;
sbit rd=P3^2;
sbit k0=P1^0;
sbit k1=P1^1;
sbit k2=P1^2;
sbit k3=P1^3;
sbit k4=P1^4;
unsigned char flag;//当flag为0、1、2、3、4时分别产生正弦波、方波、三角波、梯形波、锯齿波
unsigned char const code sin_code[256]={
0x80,0x83,0x86,0x89,0x8c,0x8f,0x92,0x95,0x98,0x9c,0x9f,0xa2,
0xa5,0xa8,0xab,0xae,0xb0,0xb3,0xb6,0xb9,0xbc,0xbf,0xc1,0xc4,
0xc7,0xc9,0xcc,0xce,0xd1,0xd3,0xd5,0xd8,0xda,0xdc,0xde,0xe0,
0xe2,0xe4,0xe6,0xe8,0xea,0xec,0xed,0xef,0xf0,0xf2,0xf3,0xf4,
0xf6,0xf7,0xf8,0xf9,0xfa,0xfb,0xfc,0xfc,0xfd,0xfe,0xfe,0xff,
0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xfe,0xfe,
0xfd,0xfc,0xfc,0xfb,0xfa,0xf9,0xf8,0xf7,0xf6,0xf5,0xf3,0xf2,
0xf0,0xef,0xed,0xec,0xea,0xe8,0xe6,0xe4,0xe3,0xe1,0xde,0xdc,
0xda,0xd8,0xd6,0xd3,0xd1,0xce,0xcc,0xc9,0xc7,0xc4,0xc1,0xbf,
0xbc,0xb9,0xb6,0xb4,0xb1,0xae,0xab,0xa8,0xa5,0xa2,0x9f,0x9c,
0x99,0x96,0x92,0x8f,0x8c,0x89,0x86,0x83,0x80,0x7d,0x79,0x76,
0x73,0x70,0x6d,0x6a,0x67,0x64,0x61,0x5e,0x5b,0x58,0x55,0x52,
0x4f,0x4c,0x49,0x46,0x43,0x41,0x3e,0x3b,0x39,0x36,0x33,0x31,
0x2e,0x2c,0x2a,0x27,0x25,0x23,0x21,0x1f,0x1d,0x1b,0x19,0x17,
0x15,0x14,0x12,0x10,0xf,0xd,0xc,0xb,0x9,0x8,0x7,0x6,0x5,0x4,
0x3,0x3,0x2,0x1,0x1,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,
0x0,0x1,0x1,0x2,0x3,0x3,0x4,0x5,0x6,0x7,0x8,0x9,0xa,0xc,0xd,
0xe,0x10,0x12,0x13,0x15,0x17,0x18,0x1a,0x1c,0x1e,0x20,0x23,
0x25,0x27,0x29,0x2c,0x2e,0x30,0x33,0x35,0x38,0x3b,0x3d,0x40,
0x43,0x46,0x48,0x4b,0x4e,0x51,0x54,0x57,0x5a,0x5d,0x60,0x63,
0x66,0x69,0x6c,0x6f,0x73,0x76,0x79,0x7c
}; //用于生成正弦
unsigned char kscan() //键盘扫描函数
{
unsigned char kscannum,t;
P1=0xff;
t=P1;
if(~(t0xff))
{
if(k0==0)
{
kscannum=1;
}
else if(k1==0)
{
kscannum=2;
}
else if(k2==0)
{
kscannum=3;
}
else if(k3==0)
{
kscannum=4;
}
else if(k4==0)
{
kscannum=5;
}
else
{
kscannum=0;
}
return kscannum;
}
}
void init_DA0832()//DA0832初始化
{
rd=0;
wr=0;
}
void fangbo()//产生方波函数
{
EA=1; //开总中断
ET0=1; //计时器T0工作
TMOD=1;
TR0=1; //开启T0
TH0=0xff; //装入初值
TL0=0x83;
}
void sin()//产生正弦波函数
{
unsigned inti;
do{
P2=sin_code[i];
i=i+1;
}while(i256);
}
void juchibo()//产生锯齿波函数
{
P2=0x00;
do{
P2=P2+1;
}while(P2=0xff);
}
void sanjiaobo()//产生三角波函数
{
P2=0x00;
do{
P2=P2+1;
}while(P20xff);
P2=0xff;
do{
P2=P2-1;
}while(P20x00);
P2=0x00;
}
void tixingbo()//产生梯形波函数
{
unsigned char i;
P2=0x00;
do{
P2=P2+1;
}while(P20xff);
P2=0xff;
for(i=255;i0;i--)
{
P2=0xff;
}
do{
P2=P2-1;
}while(P20x00);
P2=0x00;
}
void timer0(void) interrupt 1//中断函数
{
P2=~P2; //取反
TH0=0xff; //重新装入初值
TL0=0x83;
TR0=1;
}
/*主函数*/
void main()
{
init_DA0832();//初始化
do
{
flag=kscan();
}while(!flag);//等待按键按下
while(1)
{
switch(flag)
{
case 1:
do{
flag=kscan();
sin();
}while(flag==1);//产生正弦波
break;
case 2:
fangbo();
do{
flag=kscan();
}while(flag==2);//产生方波
TR0=0;
break;
case 3:
do{
flag=kscan();
sanjiaobo();
}while(flag==3);//产生三角波
break;
case 4:
do{
flag=kscan();
tixingbo();
}while(flag==4);//产生梯形波
break;
case 5:
do{
flag=kscan();
juchibo();
}while(flag==5);//产生锯齿波
break;
default:
flag=kscan();
break;
}
}
}
试用c语言编写一个能输出锯齿波信号的单片机c51程序
程序加一个的LCD1602，你选择使用
的＃include reg52.h的/ /包含头文件
？＃包括intrins.h的
＃定义UCHAR无符号的字符/ /宏定义
？＃定义UINT无符号整数
？UCHAR I，J，N，Z，/ /定义全局变量
SBIT RS = P2 ^ 0; / /定义端口
？和SBIT RW = P2 ^ 1;
SBIT E = P2 ^ 2;
SBIT K = P2 ^ 7;
SBIT K1 = P2 ^ 6;
UCHAR代码STR0 [] = {“正弦波”}; / /定义LCD1602显示的字符数组
UCHAR代码STR1 [] = {“三角波”};
UCHAR代码字符串str2 [] = {“方波”};
？的UCHAR代码表[3] [40] = / /定义的两维阵列的波形
？{
？？80H时，0x94的，0xa7，0xb9，0xca，0xd9，0xe7，0xf1，0XF8，是0xFD，
？？是0xFD，0xff，则0XF8，0xf1，0xe7，0xd9，0xca，0xb9 0xa7，0x94的，
？？80H时，0x6c，将0x55，0x46，0x35，$ 25，为0x18，0X0E，0X06，0X02，
？？为0x00，0X02，0X06，0X0E，为0x18，$ 25，0x35，0x46，0x55??的，0x6c，
？？80H时，0x8c，0x99，0xa6，0xb3，0XC0，含有0xCC，0xd9，0xe6，0xf2，
？？为0xff，0xf2，0xe6，0xd9，含有0xCC，0XC0，0xb3，0xa6，0x99，0x8c，
？？80H时，为0x73，0x66，0X5A，0x4d，0X40，地址0x33，0X26，0X1A，0X0D，
？为0x00，0X0D，0X1A，0X26，地址0x33，0X40，0x4d，为0x5A，0x66，为0x73，
？？为0xff，0xff，则是0xFF，0xFF时，为0xff，0xff，则是0xFF，0xFF时，为0xff，0xff，则
？？为0xff，0xff，则是0xFF，0xFF时，为0xff，0xff，则是0xFF，0xFF时，为0xff，0xff，则
？？0X00，0X00，0X00，0X00，0X00，0X00，0X00，0X00，0X00，0X00，
？？0X00，0X00，0X00，0X00，0X00，0X00，0X00，0X00，0X00，0X00
？};
？无效延迟（UINT Z）/ /延时程序
？{
？？？？（Z，Z 0，Z - ）
？？？
？？
？？}
？}
？无效Write_command“（UCHAR CMD）/ / LCD1602写命令程序
？{
？？RS = 0; / /选择指令寄存器
？RW = 0; / /写操作
？E = 1 / /使能端
？P1 = CMD;
？延迟时间（1）;
？E = 0;
LCD1602是不是很忙？延迟（10）; / /延时
？}
？无效WRITE_DATA（UCHAR CMD）/ / LCD1602写入数据的命令
？{
？？RS = 1; / /选择数据寄存器
？RW = 0; / /写操作
？E = 1; / /结束
？P1 = CMD;
？延迟时间（1）;
？E = 0;
LCD1602是不是很忙？延迟（10）; / /延时
？}
？的无效Lcd_init（）/ / LCD1602初始化程序
？{
？？？？Write_command（0x38）; / /设置16 * 5 * 7点阵8位数据接口
？Write_command（0X0C）/ / LCD1602打开显示，不显示光标
？Write_command（0X06）/ /读或写一个字符指针加1不动
？Write_command（0X80 +0 X00）; / /设置数据地址指针
？}
？无效显示器（）/ / LCD1602显示英语课程
？{
？？？？Lcd_init（）;
？（我== 0）
？？？
？组（n = 0，N 13，N +）
？？？
？？？WRITE_DATA（STR0 [N]）;
？？}
？？？？}
？否则，如果（我== 1）
？{
？组（n = 0，N 13，N +）
？？
？？WRITE_DATA（STR1 [N]）;
？}
？}
？其他
？{
？组（n = 0，N 13，N +）
？？
？？WRITE_DATA（字符串str2 [N]）;
？}
？}
？}
无效的主要（）/ /主函数
？{
？？？显示（）;
？而（1）
？{
？？中for（j = 0; J 40; + +）
？？？
？？？P0 =表[I] [J];
？？？
？？}
（k == 0）/ /切换程序？？
？？？
？？？？延迟时间（1）;
？？？（k == 0）;
？？？？
？？？？（K == 0）
？？？？？
？？？？+ +;
？？？？如果（i == 3）= 0;
？？？显示（）;
？？？？}
？？？？
？？？}
？？？？？？而（k == 0）;
？？}
？}
？}
dac0832 c程序
#pragma db oe sb
＃i ncludereg51.h
＃i ncludeabsacc.h
#define DAC0832 XBYTE[0x7fff] /* 定义DAC0832端口地址 */
#define uchar unsigned char
void delay(uchar t) { /* 延时函数 */
while(t--);
}
void saw(void) { /* 锯齿波发生函数 */
uchar i;
for (i=0;i255;i++) {
DAC0832=i;
}
}
void square(void) { /* 方波发生函数 */
DAC0832=0x00;
delay(0x10);
DAC0832=0xff;
delay(0x10);
}
void main(void) {
uchar i,j;
i=j=0xff;
while(i--) {
saw(); /* 产生一段锯齿波 */
}
while(j--) {
square(); /* 产生一段方波 */
}
}
at89c52产生三角波，锯齿波，方波，要求用c语言写，芯片是D0832
#includereg52.h
#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[]={"Sine Wave " "Triangle Wave " "Square Wave " "sawtooth Wave ""Select Wave: " "press No.1 key! "};
uchar idata lcd_hang2[16]={"f= 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};*/
/***********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,0x1c,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;x0;x--)
for(y=110;y0;y--);
}
void triangle_out()//三角波输出
{
DAdata=triangle_tab[wavecount++];
if(wavecount64) 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
}
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(wavecount71) 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;
}
void disp_lcd(uchar addr,uchar *temp1)
{
uchar num;
write_com(addr);
delay(1); //延时一会儿???
for(num=0;num16;num++)
{
write_date(temp1[num]);//或者这样写write_date(*(temp1+num));
delay(1);
}
}
void init_lcd()
{
//uchar num;
lcden=0; //可有可无???
rw=0; //初始化一定要设置为零，表示写数据
write_com(0x38); //使液晶显示点阵，为下面做准备
write_com(0x0c); //初始设置
write_com(0x06); //初始设置
write_com(0x01); //清零
write_com(0x80); //使指针指向第一行第一格
disp_lcd(0x80,lcd_hang1[4*16]); //在第一行显示
disp_lcd(0xc0,lcd_hang1[5*16]); //在第二行显示
/*for(num=0;num16;num++)
{
write_date(table[num]);
delay(5);
}
write_com(0x80+0x40); //给指针重新赋值，使之指向第二行第一格
for(num=0;num16;num++)
{
write_date(table1[num]);
delay(5);
} */
/*TMOD=0x01; //选用定时方式1
TH0=(65536-50000)/256; //赋初值
TL0=(65536-50000)%256;//
EA=1;//开总中断
ET0=1; //开定时器中断
TR0=1; //启动定时器*/
}
/********************1602液晶函数声明结束*********************/
void main()
{
uchar i=0;
DA_S2=0; //使DAC寄存器处于直通状态
DAdata=0;
DA_S1=1; //关闭8位输入寄存器
init_lcd();
waveform=0;
TMOD=0x01; //设置定时器0为16位工作方式
IT0=1; //设置外部中断0为下降沿触发
ET0=1; //开定时器中断
EX0=1;
EA=1;
while(1)
{
//DAout(0xff); //可输出TTL波形
//DAout(0x80);
//T_temp=32;
}
}
void timer0() interrupt 1
{
TH0=THtemp;
TL0=TLtemp;
if(waveform==0) sine_out();
else if(waveform==1) triangle_out();
else if(waveform==2) square_out();
else if(waveform==3) sawtooth_out(); //tian jian
}
void key_int0() interrupt 0
{
uchar keytemp;
uint total_freq; //总频率
EA=0; TR0=0; //关总中断与定时器
delay(5); //延时够吗???
if(key==0) //确实有按键按下而引发中断
{
keytemp=P30xf0; //获取P3口高四位的值
switch(keytemp)
{
case 0xe0://选择波形
waveform++;
if(waveform3) waveform=0; //jiang 2 gai wei 3
break;
case 0xd0: //频率按规定单位依次增加
wavefreq[waveform]++;
if(wavefreq[waveform]10) wavefreq[waveform]=1; // /*这边要用“10”，因为它比“=11”可靠
break; // 性更高,使加数有个上限，不会一直加下去*/
case 0xb0: //频率按规定单位依次衰减
wavefreq[waveform]--;
if(wavefreq[waveform]1) wavefreq[waveform]=10; //这边要用“1”，因为它比“=0”可靠性更高
break;
case 0x70: //TTL输出
DA_S2=1; //使DAC寄存器关闭
break;
}
THtemp=waveTH[waveform*10+(wavefreq[waveform]-1)]; //方括号中选取第几个数后，并把该值赋给T_temp
TLtemp=waveTL[waveform*10+(wavefreq[waveform]-1)];
total_freq= wavefreq[waveform] * freq_unit[waveform]; //求输出频率（个数*单位）
lcd_hang2[5]=total_freq%10+0x30; //在液晶中显示个位，(0x30 在液晶显示中表示数字0)
total_freq/=10; lcd_hang2[4]=total_freq%10+0x30; //在液晶中显示时十位
total_freq/=10; lcd_hang2[3]=total_freq%10+0x30; //在液晶中显示时百位
total_freq/=10; lcd_hang2[2]=total_freq%10+0x30; //在液晶中显示时千位
disp_lcd(0x80,lcd_hang1[waveform*16]); //在第一行显示
disp_lcd(0xc0,lcd_hang2); //在第二行显示
}
wavecount=0; //'抽点'计数清零
while(!key);
EA=1; TR0=1; //开启总中断与定时器
文章标题：c语言锯齿波函数,锯齿波的函数
文章出自：http://azwzsj.com/article/hesdjh.html
