구차니의 잡동사니 모음

#include <stdio.h>

int printf(const char *format, ...);

int fprintf(FILE *stream, const char *format, ...);

int sprintf(char *str, const char *format, ...);

int snprintf(char *str, size_t size, const char *format, ...);

#include <stdarg.h>

int vprintf(const char *format, va_list ap);

int vfprintf(FILE *stream, const char *format, va_list ap);

int vsprintf(char *str, const char *format, va_list ap);

int vsnprintf(char *str, size_t size, const char *format, va_list ap);

[링크 : http://linux.die.net/man/3/vsprintf] 

/*

 *  dht11.c:

 * Simple test program to test the wiringPi functions

 * DHT11 test

 */

#include <wiringPi.h>

#include <stdio.h>

#include <stdlib.h>

#include <stdint.h>

#define MAXTIMINGS 85

#define DHTPIN 7

int dht11_dat[5] = { 0, 0, 0, 0, 0 };

void read_dht11_dat()

{

uint8_t laststate = HIGH;

uint8_t counter = 0;

uint8_t j = 0, i;

float f; /* fahrenheit */

dht11_dat[0] = dht11_dat[1] = dht11_dat[2] = dht11_dat[3] = dht11_dat[4] = 0;

/* pull pin down for 18 milliseconds */

pinMode( DHTPIN, OUTPUT );

digitalWrite( DHTPIN, LOW );

delay( 18 );

/* then pull it up for 40 microseconds */

digitalWrite( DHTPIN, HIGH );

delayMicroseconds( 40 );

/* prepare to read the pin */

pinMode( DHTPIN, INPUT );

/* detect change and read data */

for ( i = 0; i < MAXTIMINGS; i++ )

{

counter = 0;

while ( digitalRead( DHTPIN ) == laststate )

{

counter++;

delayMicroseconds( 1 );

if ( counter == 255 )

{

break;

}

}

laststate = digitalRead( DHTPIN );

if ( counter == 255 )

break;

/* ignore first 3 transitions */

if ( (i >= 4) && (i % 2 == 0) )

{

/* shove each bit into the storage bytes */

dht11_dat[j / 8] <<= 1;

if ( counter > 16 )

dht11_dat[j / 8] |= 1;

j++;

}

}

/*

 * check we read 40 bits (8bit x 5 ) + verify checksum in the last byte

 * print it out if data is good

 */

if ( (j >= 40) &&

     (dht11_dat[4] == ( (dht11_dat[0] + dht11_dat[1] + dht11_dat[2] + dht11_dat[3]) & 0xFF) ) )

{

f = dht11_dat[2] * 9. / 5. + 32;

printf( "Humidity = %d.%d %% Temperature = %d.%d *C (%.1f *F)\n",

dht11_dat[0], dht11_dat[1], dht11_dat[2], dht11_dat[3], f );

}else  {

printf( "Data not good, skip\n" );

}

}

int main( void )

{

printf( "Raspberry Pi wiringPi DHT11 Temperature test program\n" );

if ( wiringPiSetup() == -1 )

exit( 1 );

while ( 1 )

{

read_dht11_dat();

delay( 1000 ); /* wait 1sec to refresh */

}

return(0);

}

[링크 : http://www.uugear.com/portfolio/dht11-humidity-temperature-sensor-module/] 

$ gcc dht11.c -lwiringPi

$ sudo ./a.out

Raspberry Pi wiringPi DHT11 Temperature test program

Humidity = 63.0 % Temperature = 26.0 *C (78.8 *F)

Data not good, skip

...

Humidity = 85.0 % Temperature = 30.0 *C (86.0 *F)

...

Sensitivity range: up to 20 feet (6 meters) 110° x 70° detection range

Power supply: 3V-9V input voltage, but 5V is ideal.

If the Rtime potentiometer is turned all the way down counter-clockwise (to 0 ohms) then

Tx = 24576 x (10K) x 0.01uF = 2.5 seconds (approx)

If the Rtime potentiometer is turned all the way up clockwise to 1 Megaohm then

Tx = 24576 x (1010K) x 0.01uF = 250 seconds (approx)

[링크 : https://learn.adafruit.com/downloads/pdf/pir-passive-infrared-proximity-motion-sensor.pdf] 

pi@raspberrypi ~ $  gpio readall

 +-----+-----+---------+------+---+-Model B2-+---+------+---------+-----+-----+

 | BCM | wPi |   Name  | Mode | V | Physical | V | Mode | Name    | wPi | BCM |

 +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+

 |     |     |    3.3v |      |   |  1 || 2  |   |      | 5v      |     |     |

 |   2 |   8 |   SDA.1 |   IN | 1 |  3 || 4  |   |      | 5V      |     |     |

 |   3 |   9 |   SCL.1 |   IN | 1 |  5 || 6  |   |      | 0v      |     |     |

 |   4 |   7 | GPIO. 7 |   IN | 1 |  7 || 8  | 1 | ALT0 | TxD     | 15  | 14  |

 |     |     |      0v |      |   |  9 || 10 | 1 | ALT0 | RxD     | 16  | 15  |

 |  17 |   0 | GPIO. 0 |  OUT | 0 | 11 || 12 | 0 | IN   | GPIO. 1 | 1   | 18  |

 |  27 |   2 | GPIO. 2 |   IN | 0 | 13 || 14 |   |      | 0v      |     |     |

 |  22 |   3 | GPIO. 3 |   IN | 0 | 15 || 16 | 0 | IN   | GPIO. 4 | 4   | 23  |

 |     |     |    3.3v |      |   | 17 || 18 | 0 | IN   | GPIO. 5 | 5   | 24  |

 |  10 |  12 |    MOSI |   IN | 0 | 19 || 20 |   |      | 0v      |     |     |

 |   9 |  13 |    MISO |   IN | 0 | 21 || 22 | 0 | IN   | GPIO. 6 | 6   | 25  |

 |  11 |  14 |    SCLK |   IN | 0 | 23 || 24 | 1 | IN   | CE0     | 10  | 8   |

 |     |     |      0v |      |   | 25 || 26 | 1 | IN   | CE1     | 11  | 7   |

 +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+

 |  28 |  17 | GPIO.17 |   IN | 0 | 51 || 52 | 0 | IN   | GPIO.18 | 18  | 29  |

 |  30 |  19 | GPIO.19 |   IN | 0 | 53 || 54 | 0 | IN   | GPIO.20 | 20  | 31  |

 +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+

 | BCM | wPi |   Name  | Mode | V | Physical | V | Mode | Name    | wPi | BCM |

 +-----+-----+---------+------+---+-Model B2-+---+------+---------+-----+-----+

pi@raspberrypi ~ $ gpio read 1

0

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

1

pi@raspberrypi ~ $ gpio read 1

0

pi@raspberrypi ~ $ gpio read 1

0

pi@raspberrypi ~ $ gpio read 1

0 

$ gpio pwm 1 30; sleep 1; gpio pwm 1 110; sleep 1;gpio pwm 1 30; sleep 1; gpio pwm 1 110; sleep 1