Driver for the DHT22 temperature and humidity sensor. More...

Files
file	arch/platform/zoul/dev/dht22.c
	Driver for the DHT22 temperature and humidity sensor.
file	arch/platform/zoul/dev/dht22.h
	Header file for the DHT22 temperature and humidity sensor.

Functions
static int	dht22_read (void)

DHT22 constants
#define	DHT22_BUFFER 5
	Buffer to store the samples.
#define	DHT22_COUNT 8
	Minimum ticks to detect a "1" bit.
#define	DHT22_MAX_TIMMING 85
	Maximum ticks in a single operation.
#define	DHT22_READING_DELAY 1
	1 us
#define	DHT22_READY_TIME 40
	40 us
#define	DHT22_START_TIME (RTIMER_SECOND / 50)
	20 ms
#define	DHT22_AWAKE_TIME (RTIMER_SECOND / 4)
	250 ms

Detailed Description

Driver for the DHT22 temperature and humidity sensor.

Function Documentation

int dht22_read ( void )

static

< 250 ms

< Buffer to store the samples

< 20 ms

< 40 us

< Maximum ticks in a single operation

< 1 us

< Minimum ticks to detect a "1" bit

< Buffer to store the samples

Definition at line 62 of file dht22.c.