求助 利用定时器的输入捕获功能捕获PWM信号的占空比 （arduino程序）

梅梅

1. #include <stdio.h>
   
2. #include <avr/interrupt.h>
   
3. #include <avr/io.h>
   
4. #include <inttypes.h>
   
5. #include <avr/signal.h>
   
6. //Counts overflovs
   
7. volatile uint16_t T4Ovs1, T4Ovs2;
   
8. //Variables holding three timestamps
   
9. volatile uint16_t Capt1, Capt2, Capt3;
   
10. //capture Flag
    
11. volatile uint8_t Flag;
    
12. volatile uint8_t TEMP;
    
13. volatile uint8_t Dutycycle;
    
14. #define pin 49
    
15. //Initialize timer
    
16. void InitTimer4(void)
    
17. {
    
18.   cli();
    
19.   TCCR4A=0x00;
    
20.   //Set Initial Timer value
    
21.   TCNT4=0;
    
22.   //First capture on rising edge
    
23.   TCCR4B|=(1<<ICES4);
    
24.   //Enable input capture and overflow interrupts
    
25.   TIMSK4|=(1<<ICIE4)|(1<<TOIE4);
    
26.   TCCR4B|=(1<<ICNC4);
    
27.   TCCR4B|=(1<<CS40)|(1<<CS41);
    
28.   sei();
    
29. }
    
30. 
    
31. //capture ISR
    
32. ISR(TIMER4_CAPT_vect)
    
33. {
    
34.   Serial.print("jin ru zhong duan bu huo cheng xu");
    
35.   Serial.print('\n');
    
36.   if (Flag==0)
    
37.   { //save captured timestamp
    
38.     Capt1=ICR4;
    
39.     //change capture on falling edge
    
40.     TCCR4B&=~(1<<ICES4);
    
41.     //reset overflows
    
42.     T4Ovs2=0;
    
43.     Serial.print("bu  dao shang she yan");
    
44.     Serial.print('\n');
    
45.     Serial.print("<Capture1>:");        /*串口输出第一次上升沿捕获时刻*/
    
46.     Serial.print(Capt1);
    
47.     Serial.print('\n');
    
48.   }
    
49.   if (Flag==1)
    
50.   {  
    
51.     Capt2=ICR4;
    
52.     //change capture on rising edge
    
53.     TCCR4B|=(1<<ICES4);
    
54.     //save first overflow counter
    
55.     T4Ovs1=T4Ovs2;
    
56.     Serial.print("bu huo dao xia jiang yan");
    
57.     Serial.print('\n');
    
58.     Serial.print("<Capture2>:");        /*串口输出第一次上升沿捕获时刻*/
    
59.     Serial.print(Capt2);
    
60.     Serial.print('\n');
    
61.   }
    
62.   if (Flag==2)
    
63.   {
    
64.     Capt3=ICR4;
    
65.     //stop input capture and overflow interrupts
    
66.     TIMSK4&=~((1<<ICIE4)|(1<<TOIE4));
    
67.     Serial.print("di er ci bu huo dao shang sheng yan");
    
68.     Serial.print('\n');
    
69.     Serial.print("<Capture3>:");        /*串口输出第一次上升沿捕获时刻*/
    
70.     Serial.print(Capt3);
    
71.     Serial.print('\n');
    
72.   }
    
73.   //increment Flag
    
74.   Flag++;
    
75. }
    
76. //Overflow ISR
    
77. ISR(TIMER4_OVF_vect)
    
78. {
    
79.   //increment overflow counter
    
80.   T4Ovs2++;
    
81. }
    
82. void setup()
    
83. {
    
84.   pinMode(pin,INPUT);
    
85.   //dutycycle result holder
    
86.   InitTimer4();
    
87.   Serial.begin(9600);
    
88.   sei();
    
89. 
    
90. }
    
91. void loop()
    
92. {
    
93.   Dutycycle=(((uint8_t)((((uint32_t)(Capt2-Capt1)+((uint32_t)T4Ovs1*0x10000L))*100L)
    
94.     /((uint32_t)(Capt3-Capt1)+((uint32_t)T4Ovs2*0x10000L)))));
    
95.   Serial.print("<High Time>:");      /*串口输出高电平的持续时间*/
    
96.   Serial.print((Capt2-Capt1+T4Ovs1*0x10000L*100L)*0.5);  
    
97.   Serial.print("microsecond");
    
98.   Serial.print('\n');         
    
99.   Serial.print("<Total Time>:");      /*串口输出脉冲周期*/
    
100.   Serial.print((Capt3-Capt1+T4Ovs2*10000L)*0.5);
     
101.   Serial.print("milsecond");        
     
102.   Serial.print('\n');
     
103.   Serial.print("<Dutycycle>;");/*串口输出占空比*/
     
104.   Serial.print(Dutycycle);
     
105.   Serial.print('\n');
     
106.   //send Duty Cycle value to LCD or USART
     
107.   TCNT4=0;
     
108.   //clear flag
     
109.   Flag=0;       
     
110.   //clear overflow counters;
     
111.   T4Ovs1=0;
     
112.   T4Ovs2=0;
     
113.   //clear interrupt flags to avoid any pending interrupts
     
114.   TIFR4|=(1<<ICF4)|(1<<TOV4);
     
115.   //enable input capture and overflow interrupts
     
116.   TIMSK4|=(1<<ICIE4)|(1<<TOIE4);
     
117. }
     

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GeMarK

楼主是女的？

lby

我下载进去了一直都是