现在想用外部中断0和外部中断1来测双路脉冲的占空比,实现的方法是先把定时器0设置成TMOD |=0x08(//T0开始计时的条件是INT0脚为高电平及TR0置1时)模式,以此来测P3^2脚输入脉冲高电平的时间,然后外部中断0是下降沿中断,通过两次下降沿中断来测P3^2脚输入脉冲的周期,以此来算占空比;同理用同样的再去测P3^3脚输入脉冲的占空比,两路脉冲每测试完以此刷新一下屏幕显示,然后延迟500ms再去测两个输入脉冲,如此循环,可是测量的结果却不对,P3^2脚的输入脉冲没有问题,但是P3^3脚输入脉冲的周期测试不准确,正常是8点几毫秒,但是测出来的值时零点几毫秒,但是高电平时间是对的。思考了好长时间实在找不到错误,因此来寻求大神的帮助,望不吝赐教。
单片机源程序如下:
- #include "stc15.h"
- #include "COMMON.H"
- #include "LCD12864.H"
- ulong atime_h =0; //a路正脉冲频宽
- ulong atime = 0; //a路脉冲周期
- ulong Dutycycle_a = 0; //a路脉冲占空比
- uint int0_count = 0; //外部中断0的中断次数
- ulong btime_h =0; //b路正脉冲频宽
- ulong btime = 0; //b路脉冲周期
- ulong Dutycycle_b = 0; //b路脉冲占空比
- uint int1_count = 0; //外部中断1的中断次数
- uint flag = 0;
- void display_data(uchar address,ulong b) //脉冲周期或正脉冲频宽的显示函数 (6位)
- {
- lcd_write_byte(0xf8,address);
- lcd_write_byte(0xfa,b/100000+0x30);
- lcd_write_byte(0xfa,(b%100000)/10000+0x30);
- lcd_write_byte(0xfa,(b%10000)/1000+0x30);
- lcd_write_byte(0xfa,(b%1000)/100+0x30);
- lcd_write_byte(0xfa,(b%100)/10+0x30);
- lcd_write_byte(0xfa,(b%10)+0x30);
- }
- void display_data1(uchar address,ulong b)
- {
- lcd_write_byte(0xf8,address);
- lcd_write_byte(0xfa,b/100+0x30);
- lcd_write_byte(0xfa,(b%100)/10+0x30);
- lcd_write_byte(0xfa,0x2e); //小数点
- lcd_write_byte(0xfa,(b%10)+0x30);
- }
- void int0_init()
- {
- IT0 = 1; //为 1 是下降沿; 为 0 是下降沿或上升沿
- EX0 = 0; //为 1 允许中断; 为 0 是禁止中断
- }
- void int1_init()
- {
- IT1 = 1; //为 1 是下降沿; 为 0 是下降沿或上升沿
- EX1 = 0; //为 1 允许中断; 为 0 是禁止中断
- }
- void t0_init() //65536us@12MHz
- {
- AUXR &= 0x7F; //定时器时钟12T模式
- TMOD &= 0xF8; //设置定时器模式
- //TMOD |= 0x08; //T0开始计时的条件是INT0脚为高电平及TR0置1时
- TL0 = 0x00; //设置定时初值
- TH0 = 0x00; //设置定时初值
- TF0 = 0; //清除TF0标志
- ET0 = 1; //允许T0中断
- TR0 = 0; //定时器0停止计时
- }
- void t1_init() //65536us@12MHz
- {
- AUXR &= 0xBF; //定时器时钟12T模式
- TMOD &= 0x8F; //设置定时器模式
- //TMOD |= 0x80; //T1开始计时的条件是INT1脚为高电平及TR1置1时
- TL1 = 0x00; //设置定时初值
- TH1 = 0x00; //设置定时初值
- TF1 = 0; //清除TF1标志
- ET1 = 1; //允许T1中断
- TR1 = 0; //定时器1停止计时
- }
- void show_freq()
- {
- if(flag == 1)
- {
- display_data1(0x91,Dutycycle_a);
- display_data(0x95,atime_h);
- display_data1(0x89,Dutycycle_b);
- display_data(0x8D,btime);
- delay_xms(500);
- flag = 0;
- }
- else
- {
- TMOD |= 0x08;
- EX0 = 1;
- }
- }
- void fuwei() //复位函数
- {
- TR0 = 0;
- TR1 = 0;
- EX0 = 0;
- EX1 = 0;
- TH0 = 0;
- TL0 = 0;
- TH1 = 0;
- TL1 = 0;
- int0_count = 0;
- int1_count = 0;
- }
- void main()
- {
- stc_init();
- int0_init();
- int1_init();
- t0_init();
- t1_init();
- lcd_init();
- delay_xms(5);
- lcd_clean();
- delay_xms(5);
- lcd_write_string(0x80," 占空比 正周期");
- lcd_write_string(0x90,"A:");
- lcd_write_string(0x93,"%");
- lcd_write_string(0x88,"B:");
- lcd_write_string(0x8B,"%");
- lcd_write_string(0x98,"C:");
- lcd_write_string(0x9B,"%");
- delay_xms(5);
- EA=1;
- while(1)
- {
- show_freq();
- }
- }
- void int0() interrupt 0
- {
- if(flag == 0)
- {
- int0_count++;
- }
- if(int0_count == 1)
- {
- TR1 = 1;
- TR0 = 1;
- }
- if(int0_count == 2)
- {
- TR0 = 0;
- TR1 = 0;
- atime_h = TH0<<8|TL0;
- atime = TH1<<8|TL1;
- Dutycycle_a = atime_h*1000/atime;
- EX0 = 0;
- TH0 = 0;
- TL0 = 0;
- TH1 = 0;
- TL1 = 0;
- int0_count = 0;
- TMOD &= 0xF7;
- TMOD |= 0x80;
- EX1 = 1;
- }
- }
- void int1() interrupt 2
- {
- if(flag == 0)
- {
- int1_count++;
- }
- if(int1_count == 1)
- {
- TR1 = 1;
- TR0 = 1;
- }
- if(int1_count == 2)
- {
- TR0 = 0;
- TR1 = 0;
- btime_h = TH1<<8|TL1;
- btime = TH0<<8|TL0;
- Dutycycle_b = btime_h*1000/btime;
- EX1 = 0;
- TH0 = 0;
- TL0 = 0;
- TH1 = 0;
- TL1 = 0;
- int1_count = 0;
- TMOD &= 0x7F;
- flag = 1;
- }
- }
- void t0() interrupt 1
- {
- fuwei();
- }
- void t1() interrupt 3
- {
- fuwei();
- }
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