main.swift

import Glibc
import Foundation

func initLCD() -> HD44780LCD {
	let gpios = SwiftyGPIO.getGPIOsForBoard(.RaspberryPiRev2)
	let lcd = HD44780LCD(rs:gpios[.P25]!,e:gpios[.P24]!,d7:gpios[.P22]!,d6:gpios[.P27]!,d5:gpios[.P17]!,d4:gpios[.P23]!,width:20,height:4)
	return lcd	
}

	let gpios = SwiftyGPIO.getGPIOsForBoard(.RaspberryPiRev2)	
	let lcd = initLCD()
	lcd.clearScreen()
	lcd.cursorHome()

	let dht = DHT(pin: gpios[.P4]!)

	var temperature = 0.0
	var humidity = 0.0

	// samples every 5s, outputs last good temp/humidty & the # of seconds since last good reading
	var startTime:timeval = timeval(tv_sec: 0, tv_usec: 0)
	var endTime:timeval = timeval(tv_sec: 0, tv_usec: 0)			

    gettimeofday(&startTime,nil)
	while (true) {
		do {
			(temperature,humidity) = try dht.read(true)
		    gettimeofday(&startTime,nil)
			print("temp: \(temperature)  hum: \(humidity)")
		} catch (DHTError.InvalidNumberOfPulses) {
			let errorMessage = "INVALID PULSES"
			print(errorMessage)
		} catch (DHTError.InvalidChecksum) {
			let errorMessage = "INVALID CHECKSUM"
			print(errorMessage)
		}

		gettimeofday(&endTime,nil)

		lcd.clearScreen()
		lcd.cursorHome()
		lcd.printString(0,y:0,what:"Temp: \(temperature) \(endTime.tv_sec - startTime.tv_sec)s",usCharSet:true)
		lcd.printString(0,y:1,what:"Humidity: \(humidity)",usCharSet:true)			
	
		sleep(5)		
	}