AdvancedIO

Functions
void	tone (uint8_t pin, uint32_t frequency, uint64_t duration=0)
void	noTone (uint8_t pin)
void	shiftOut (uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val)
uint32_t	shiftIn (uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder)
unsigned long	pulseIn (uint8_t pin, uint8_t state, unsigned long timeout=1000000L)
unsigned long	pulseInLong (uint8_t pin, uint8_t state, unsigned long timeout=1000000L)

Detailed Description

Function Documentation

tone()

void tone	(	uint8_t	pin,
		uint32_t	frequency,
		uint64_t	duration = 0
	)

Description

Generates a square wave of the specified frequency (and 50% duty cycle) on a pin. A duration can be specified, otherwise the wave continues until a call to noTone().

Only one tone can be generated at a time. If a tone is already playing on a different pin, the call to tone() will have no effect. If the tone is playing on the same pin, the call will set its frequency.

Syntax

tone(pin, frequency);
tone(pin, frequency, duration);

Parameters

pin	The device pin on which to generate the tone
frequency	The frequency of the tone in hertz
duration(optional)	The duration of the tone in milliseconds(default = no timeout)

Returns

void

Example

uint8_t ledPin = 36; 
uint8_t pulsePin = 13;
unsigned long duration;

void setup() {
  Serial.begin(115200);
  pinMode(pulsePin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  duration = pulseIn(pulsePin, LOW);
  Serial.print("Pulse duration = ");
  Serial.print((float)duration/1000000);
  Serial.println(" sec");

  if(duration >= 15000000)
    noTone(ledPin);
  else if(duration >= 10000000)
    tone(ledPin, 494, 5000);
  else if(duration >= 5000000)
    tone(ledPin, 494);
}

noTone()

void noTone

(

uint8_t

pin

)

Description

Stops the generation of a square wave triggered by tone()

Syntax

noTone(pin);

Parameters

pin	The device pin on which to stop generating the tone

Returns

void

Example

uint8_t ledPin = 36;
uint8_t pulsePin = 13;
unsigned long duration;

void setup() {
  Serial.begin(115200);
  pinMode(pulsePin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  duration = pulseIn(pulsePin, LOW);
  Serial.print("Pulse duration = ");
  Serial.print((float)duration/1000000);
  Serial.println(" sec");

  if(duration >= 15000000)
    noTone(ledPin);
  else if(duration >= 10000000)
    tone(ledPin, 494, 5000);
  else if(duration >= 5000000)
    tone(ledPin, 494);
}

shiftOut()

void shiftOut	(	uint8_t	dataPin,
		uint8_t	clockPin,
		uint8_t	bitOrder,
		uint8_t	val
	)

Description

Shifts out a byte of data one bit at a time. Starts from either the most (i.e. the leftmost) or least (rightmost) significant bit. Each bit is written in turn to a data pin, after which a clock pin is pulsed (taken high, then low) to indicate that the bit is available.

Syntax

shiftOut(dataPin, clockPin, bitOrder, val);

Parameters

dataPin	the pin on which to output each bit
clockPin	the pin to toggle once the dataPin has been set to the correct value
bitOrder	which order to shift out the bits; either MSBFIRST or LSBFIRST
val	the data to shift out

Returns

void

shiftIn()

uint32_t shiftIn	(	uint8_t	dataPin,
		uint8_t	clockPin,
		uint8_t	bitOrder
	)

Description

Shifts in a byte of data one bit at a time. Starts from either the most (i.e. the leftmost) or least (rightmost) significant bit. For each bit, the clock pin is pulled high, the next bit is read from the data line, and then the clock pin is taken low.

Syntax

byte incoming = shiftIn(dataPin, clockPin, bitOrder);

Parameters

dataPin	the pin on which to output each bit
cloackPin	the pin to toggle once the dataPin has been set to the correct value
bitOrder	which order to shift out the bits; either MSBFIRST or LSBFIRST

Returns

The value read(Type: byte);

pulseIn()

unsigned long pulseIn	(	uint8_t	pin,
		uint8_t	state,
		unsigned long	timeout = 1000000L
	)

Description

Reads a pulse (either HIGH or LOW) on a pin. For example, if value is HIGH, pulseIn() waits for the pin to go from LOW to HIGH, starts timing, then waits for the pin to go LOW and stops timing. Returns the length of the pulse in microseconds or gives up and returns 0 if no complete pulse was received within the timeout.

Syntax

pulseIn(pin, state);
pulseIn(pin, state, timeout);

Parameters

pin	the pin on which you want to read a pulse
state	type of pulse to read: either HIGH or LOW
timeout(optional)	the number of microseconds to wait for the pulse to start; default is one second

Returns

The length of the pulse (in microseconds) or 0 if no pulse started before the timeout(Type: unsgined long)

Example

uint8_t ledPin = 36;
uint8_t pulsePin = 13;
unsigned long duration;

void setup() {
  Serial.begin(115200);
  pinMode(pulsePin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  duration = pulseIn(pulsePin, LOW);
  Serial.print("Pulse duration = ");
  Serial.print((float)duration/1000000);
  Serial.println(" sec");

  if(duration >= 15000000)
    noTone(ledPin);
  else if(duration >= 10000000)
    tone(ledPin, 494, 5000);
  else if(duration >= 5000000)
    tone(ledPin, 494);
}

pulseInLong()

unsigned long pulseInLong	(	uint8_t	pin,
		uint8_t	state,
		unsigned long	timeout = 1000000L
	)

Description

pulseInLong() is an alternative to pulseIn() which is better at handling long pulse and interrupt affected scenarios

Syntax

pulseInLong(pin, state);
pulseInLong(pin, state, timeout);

Parameters

pin	the pin on which you want to read a pulse
state	type of pulse to read: either HIGH or LOW
timeout(optional)	the number of microseconds to wait for the pulse to start; default is one second

Returns

The length of the pulse (in microseconds) or 0 if no pulse started before the timeout(Type: unsigned long)