rmk 0.1.3

Keyboard firmware written in Rust
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119

use crate::debounce::Debouncer;
use core::convert::Infallible;
use embassy_time::{Duration, Instant, Timer};
use embedded_hal::digital::{InputPin, OutputPin};

/// KeyState represents the state of a key.
#[derive(Copy, Clone, Debug)]
pub(crate) struct KeyState {
    pub(crate) pressed: bool,
    pub(crate) changed: bool,
    hold_start: Option<Instant>,
}

impl Default for KeyState {
    fn default() -> Self {
        Self::new()
    }
}

impl KeyState {
    fn new() -> Self {
        KeyState {
            pressed: false,
            changed: false,
            hold_start: None,
        }
    }

    fn start_timer(&mut self) {
        self.hold_start = Some(Instant::now());
    }

    fn elapsed(&self) -> Option<Duration> {
        match self.hold_start {
            Some(t) => Instant::now().checked_duration_since(t),
            None => None,
        }
    }

    fn clear_timer(&mut self) {
        self.hold_start = None;
    }
}

/// Matrix is the physical pcb layout of the keyboard matrix.
pub struct Matrix<
    In: InputPin,
    Out: OutputPin,
    const INPUT_PIN_NUM: usize,
    const OUTPUT_PIN_NUM: usize,
> {
    /// Input pins of the pcb matrix
    input_pins: [In; INPUT_PIN_NUM],
    /// Output pins of the pcb matrix
    output_pins: [Out; OUTPUT_PIN_NUM],
    /// Debouncer
    debouncer: Debouncer<INPUT_PIN_NUM, OUTPUT_PIN_NUM>,
    /// Key state matrix
    key_states: [[KeyState; INPUT_PIN_NUM]; OUTPUT_PIN_NUM],
}

impl<
        In: InputPin<Error = Infallible>,
        Out: OutputPin<Error = Infallible>,
        const INPUT_PIN_NUM: usize,
        const OUTPUT_PIN_NUM: usize,
    > Matrix<In, Out, INPUT_PIN_NUM, OUTPUT_PIN_NUM>
{
    /// Create a matrix from input and output pins.
    pub(crate) fn new(input_pins: [In; INPUT_PIN_NUM], output_pins: [Out; OUTPUT_PIN_NUM]) -> Self {
        Matrix {
            input_pins,
            output_pins,
            debouncer: Debouncer::new(),
            key_states: [[KeyState::new(); INPUT_PIN_NUM]; OUTPUT_PIN_NUM],
        }
    }

    /// Do matrix scanning, the result is stored in matrix's key_state field.
    pub(crate) async fn scan(&mut self) -> Result<(), Infallible> {
        for (out_idx, out_pin) in self.output_pins.iter_mut().enumerate() {
            // Pull up output pin, wait 1us ensuring the change comes into effect
            out_pin.set_high()?;
            Timer::after_micros(1).await;
            for (in_idx, in_pin) in self.input_pins.iter_mut().enumerate() {
                // Check input pins and debounce
                self.debouncer.debounce(
                    in_idx,
                    out_idx,
                    in_pin.is_high()?,
                    &mut self.key_states[out_idx][in_idx],
                );
            }
            out_pin.set_low()?;
        }
        Ok(())
    }

    /// When a key is pressed, some callbacks some be called, such as `start_timer`
    pub(crate) fn key_pressed(&mut self, row: usize, col: usize) {
        // COL2ROW
        #[cfg(feature = "col2row")]
        self.key_states[col][row].start_timer();

        // ROW2COL
        #[cfg(not(feature = "col2row"))]
        self.key_states[row][col].start_timer();
    }

    pub(crate) fn get_key_state(&mut self, row: usize, col: usize) -> KeyState {
        // COL2ROW
        #[cfg(feature = "col2row")]
        return self.key_states[col][row];

        // ROW2COL
        #[cfg(not(feature = "col2row"))]
        return self.key_states[row][col];
    }
}