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硬件：

树莓派 2.0

DHT模块 接树莓派5V GND GPIO1

功能：读取传感器数据并打印出来

1. //
2. //mydht11.c
3. //
4. #include
5. #include
6. #include
8. typedefunsignedcharuint8;
9. typedefunsignedintuint16;
10. typedefunsignedlonguint32;
12. #define HIGH_TIME 32
14. intpinNumber =1;//use gpio1 to read data
15. uint32 databuf;
19. uint8 readSensorData(void)
20. {
21. uint8 crc;
22. uint8 i;
24. pinMode(pinNumber,OUTPUT);// set mode to output
25. digitalWrite(pinNumber, 0);// output a high level
26. delay(25);
27. digitalWrite(pinNumber, 1);// output a low level
28. pinMode(pinNumber, INPUT);// set mode to input
29. pullUpDnControl(pinNumber,PUD_UP);
31. delayMicroseconds(27);
32. if(digitalRead(pinNumber)==0)//SENSOR ANS
33. {
34. while(!digitalRead(pinNumber));//wait to high
36. for(i=0;i<32;i++)
37. {
38. while(digitalRead(pinNumber));//data clock start
39. while(!digitalRead(pinNumber));//data start
40. delayMicroseconds(HIGH_TIME);
41. databuf*=2;
42. if(digitalRead(pinNumber)==1)//1
43. {
44. databuf++;
45. }
46. }
48. for(i=0;i<8;i++)
49. {
50. while(digitalRead(pinNumber));//data clock start
51. while(!digitalRead(pinNumber));//data start
52. delayMicroseconds(HIGH_TIME);
53. crc*=2;
54. if(digitalRead(pinNumber)==1)//1
55. {
56. crc++;
57. }
58. }
59. return1;
60. }
61. else
62. {
63. return0;
64. }
65. }
67. intmain (void)
68. {
70. printf("Use GPIO1 to read data!\n");
72. if(-1 == wiringPiSetup()) {
73. printf("Setup wiringPi failed!");
74. return1;
75. }
77. pinMode(pinNumber, OUTPUT);// set mode to output
78. digitalWrite(pinNumber, 1);// output a high level
80. printf("Enter OS-------\n");
81. while(1) {
82. pinMode(pinNumber,OUTPUT);// set mode to output
83. digitalWrite(pinNumber, 1);// output a high level
84. delay(3000);
85. if(readSensorData())
86. {
87. printf("Congratulations ! Sensor data read ok!\n");
88. printf("RH:%d.%d\n",(databuf>>24)&0xff,(databuf>>16)&0xff);
89. printf("TMP:%d.%d\n",(databuf>>8)&0xff,databuf&0xff);
90. databuf=0;
91. }
92. else
93. {
94. printf("Sorry! Sensor dosent ans!\n");
95. databuf=0;
96. }
97. }
98. return0;
99. }