yet another DHT11 Class for Arduino

Development Libraries
37

from Arduino.h

#define HIGH 0x1
#define LOW  0x0

#define INPUT 0x0
#define OUTPUT 0x1
#define INPUT_PULLUP 0x2

HIGH and INPUT_PULLUP is clearly different values but digitalWrite handles them identically, so no difference in electrical behaviour.

from wiring_digital.c

void digitalWrite(uint8_t pin, uint8_t val)
{
	uint8_t timer = digitalPinToTimer(pin);
	uint8_t bit = digitalPinToBitMask(pin);
	uint8_t port = digitalPinToPort(pin);
	volatile uint8_t *out;

	if (port == NOT_A_PIN) return;

	// If the pin that support PWM output, we need to turn it off
	// before doing a digital write.
	if (timer != NOT_ON_TIMER) turnOffPWM(timer);

	out = portOutputRegister(port);

	uint8_t oldSREG = SREG;
	cli();

	if (val == LOW) {
		*out &= ~bit;
	} else {
		*out |= bit;
	}

	SREG = oldSREG;
}