电子测量 频率计实验.doc

实验名称：频率与周期的数字测量 实验目的：掌握频率与周期的测量数字方法 了解频率计的基本结构与设计方法 用51单片机设计的简易频率电路图 实验主程序： #include reg51.h #include LCD1602.h sbit CLR = P3^0; sbit FGT = P3^1; sbit f = P3^2; unsigned char TempBuffer[12]; void IntToStr(unsigned int t, unsigned char *str, unsigned char n) { unsigned char a[5]; char i, j; a[0]=(t/10000)%10; //取得整数值到数组 a[1]=(t/1000)%10; a[2]=(t/100)%10; a[3]=(t/10)%10; a[4]=(t/1)%10; for(i=0; i5; i++) //转成ASCII码 a[i]=a[i]+0; for(i=0; a[i]==0 i=3; i++); for(j=5-n; ji; j++) //填充空格 { *str= ; str++; } for(; i5; i++) { *str=a[i]; str++; } //加入有效的数字 *str=\0; } void Delay1ms(unsigned int count) { unsigned int i,j; for(i=0;icount;i++) for(j=0;j120;j++); } unsigned int Count = 0; long Freq = 0; void cn() interrupt 3 //计数器中断，测量闸门时间内的计数值 { Count++; } void Timer() interrupt 1 //定时中断，产生闸门时间 { static unsigned char temp = 0; TH0 = 0x3c; TL0 = 0xe3; Freq--; if (++temp==10) { FGT = 0; //关闭闸门 Freq = 65536L*256L*Count + 256L*(TH1*256+TL1)+P1; //频率计算 Freq *=2; TH1 = TL1= 0; Count =0; temp =0; CLR = 1; CLR = 0; FGT = 1; //打开闸门 TH0 = 0x3c; TL0 = 0xb8; } } void ini() //定时计数器初始化程序 { TMOD = 0x51; TH0 = 0x3c; TL0 = 0; TH1 = 0; TL1 = 0; TR1 = 1; ET1 = 1; TR0 = 1; ET0 = 1; EA = 1; } void main() { LCD_Initial(); //液晶显示初始化 GotoXY(0,0); Print(The 1602LCD Test); GotoXY(0,1); Print(Freq: Hz); ini(); CLR=0; while(1) { IntToStr(Freq,TempBuffer[0],5); //显示数据转换 GotoXY(5,1); Print(TempBuffer[0]); / /显示频率 Delay1ms(100); } }