blue_pill_more/src/rotary.rs

60 lines
1.3 KiB
Rust

use embedded_hal as hal;
use either::Either;
use hal::digital::v2::InputPin;
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct Rotary<A, B> {
pub pin_a: A,
pub pin_b: B,
prev_a: bool,
prev_c: bool,
}
/// The encoder direction is either `Clockwise`, `CounterClockwise`, or `None`
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum Direction {
/// A clockwise turn
Clockwise,
/// A counterclockwise turn
CounterClockwise,
/// No change
None,
}
impl<A, B> Rotary<A, B>
where
A: InputPin,
B: InputPin,
{
pub fn new(pin_a: A, pin_b: B) -> Self {
Self {
pin_a,
pin_b,
prev_a: false,
prev_c: false,
}
}
pub fn update(&mut self) -> Result<Direction, Either<A::Error, B::Error>> {
let a = self.pin_a.is_high().map_err(Either::Left)?;
let dir = if a != self.prev_a {
self.prev_a = a;
let b = self.pin_b.is_high().map_err(Either::Right)?;
if b != self.prev_c {
self.prev_c = b;
if a == b {
Direction::CounterClockwise
} else {
Direction::Clockwise
}
} else {
Direction::None
}
} else {
Direction::None
};
Ok(dir)
}
}