Struct Contact 

pub struct Contact<P> { /* private fields */ }

An on/off part on an input line: a button, a float switch, a motion detector.

Examples

use pamoja_core::Sensor;
use pamoja_gpio::pin::Polarity;
use pamoja_gpio::switch::Contact;
use pamoja_hal::digital::PinState;
use pamoja_hal::script::{block_on, PinScript};

// A float switch pulled up, which closes to ground when the tank is full.
let line = PinScript::new([PinState::High, PinState::Low]);
let mut full = Contact::new(line, Polarity::ActiveLow);
assert!(!block_on(full.read())?);
assert!(block_on(full.read())?);

Implementations

impl<P> Contact<P>

pub fn new(pin: P, polarity: Polarity) -> Contact<P>

Wraps an input line.

Arguments

• pin - the input line.
• polarity - which level means the contact is asserted.

Returns

The contact.

pub fn active_high(pin: P) -> Contact<P>

Wraps a line that reads high when asserted.

Arguments

• pin - the input line.

Returns

The contact.

pub fn active_low(pin: P) -> Contact<P>

Wraps a line pulled up that a closing contact takes low, the common wiring for a button or a float switch.

Arguments

• pin - the input line.

Returns

The contact.

pub fn polarity(&self) -> Polarity

Returns the polarity the contact reads with.

pub fn release(self) -> P

Gives back the line.

Returns

The pin the contact was built from.

impl<P: InputPin> Contact<P>

pub fn level(&mut self) -> Result<Level, P::Error>

Reads the physical level of the line.

Returns

The level, before the polarity is applied.

Errors

Returns the pin’s error if the line cannot be read.

pub fn is_asserted(&mut self) -> Result<bool, P::Error>

Reads whether the contact is asserted.

Returns

true when the line sits at the polarity’s asserted level.

Errors

Returns the pin’s error if the line cannot be read.

Trait Implementations

impl<P: Debug> Debug for Contact<P>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<P> Sensor for Contact<P>

where P: InputPin + Send, P::Error: Debug,

type Reading = bool

The value produced by a single read, for example a temperature or a fix.

async fn read(&mut self) -> Result<bool>

Takes a single reading from the sensor.

fn map<F, T>(self, select: F) -> Map<Self, F>

where Self: Sized, F: FnMut(Self::Reading) -> T,

Wraps this sensor so every reading passes through select first.