Struct Matrix

pub struct Matrix<C, R, const CS: usize, const RS: usize, D>
where
    C: InputPin,
    R: OutputPin,
    D: DelayNs,
{ /* private fields */ }

Describes the hardware-level matrix of switches.

Generic parameters are in order: The type of column pins, the type of row pins, the number of columns and rows. NOTE: In order to be able to put different pin structs in an array they have to be downgraded (stripped of their numbers etc.). Most HAL-s have a method of downgrading pins to a common (erased) struct. (for example see stm32f0xx_hal::gpio::PA0::downgrade)

TIM5 is used to provide a delay during the matrix scanning.

Implementations

impl<C, R, const CS: usize, const RS: usize, D> Matrix<C, R, CS, RS, D>

where C: InputPin, R: OutputPin, D: DelayNs,

pub fn new<E>( cols: [C; CS], rows: [R; RS], delay: D, select_delay_us: u32, unselect_delay_us: u32, ) -> Result<Self, E>

where C: InputPin<Error = E>, R: OutputPin<Error = E>,

Creates a new Matrix.

Assumes columns are pull-up inputs, and rows are output pins which are set high when not being scanned.

Trait Implementations

impl<C, R, const CS: usize, const RS: usize, D, E: Debug> MatrixScanner<CS, RS, E> for Matrix<C, R, CS, RS, D>

where C: InputPin<Error = E>, R: OutputPin<Error = E>, D: DelayNs,

fn get(&mut self) -> Result<[[bool; CS]; RS], E>

Scans the matrix and checks which keys are pressed.

Every row pin in order is pulled low, and then each column pin is tested; if it’s low, the key is marked as pressed.

Delays for a bit after setting each pin, and after clearing each pin.

fn is_boot_key_pressed(&mut self) -> bool

Check whether SW_1_1 is pressed.