debounce key readout

src/keyboard.rs

@@ -42,17 +42,13 @@ impl KeyPress {
     }
 }
 
+#[derive(uDebug, Clone, Copy, PartialEq, Eq)]
 pub struct KeyReadout {
+    display_no: usize,
     kn: bool,
     ko: bool,
 }
 
-impl KeyReadout {
-    pub fn to_keypress(&self, display_no: usize) -> Option<KeyPress> {
-        KeyPress::map(display_no, self.kn, self.ko)
-    }
-}
-
 pub struct Keyboard<KN, KO> {
     kn: KN,
     ko: KO,
@@ -63,11 +59,12 @@ impl<KN: AdcChannel<Atmega, ADC>, KO: AdcChannel<Atmega, ADC>> Keyboard<KN, KO>
         Keyboard { kn, ko }
     }
 
-    pub fn read(&self, adc: &mut Adc) -> Option<KeyReadout> {
+    pub fn read(&self, adc: &mut Adc, display_no: usize) -> Option<KeyReadout> {
         let kn = adc.read_blocking(&self.kn);
         let ko = adc.read_blocking(&self.ko);
         if kn > KEYBOARD_ADC_THRESHOLD || ko > KEYBOARD_ADC_THRESHOLD {
             Some(KeyReadout {
+                display_no,
                 kn: kn > KEYBOARD_ADC_THRESHOLD,
                 ko: ko > KEYBOARD_ADC_THRESHOLD,
             })
@@ -79,13 +76,13 @@ impl<KN: AdcChannel<Atmega, ADC>, KO: AdcChannel<Atmega, ADC>> Keyboard<KN, KO>
 
 #[derive(Default)]
 pub struct Debounce {
-    record: [Option<KeyPress>; DEBOUNCE_DEPTH],
+    record: [Option<KeyReadout>; DEBOUNCE_DEPTH],
     pos: usize,
-    last: Option<KeyPress>,
+    last: Option<KeyReadout>,
 }
 
 impl Debounce {
-    pub fn input(&mut self, key: Option<KeyPress>) -> Option<KeyPress> {
+    pub fn input(&mut self, key: Option<KeyReadout>) -> Option<KeyPress> {
         self.record[self.pos] = key;
         self.pos += 1;
         if self.pos >= self.record.len() {
@@ -93,7 +90,9 @@ impl Debounce {
         }
         if self.record.iter().all(|hist| hist == &key) && self.last != key {
             self.last = key;
-            key
+            key.and_then(|key_readout| {
+                KeyPress::map(key_readout.display_no, key_readout.kn, key_readout.ko)
+            })
         } else if self.record.iter().all(|hist| hist == &None) {
             self.last = None;
             None

src/main.rs

@@ -480,7 +480,7 @@ fn main() -> ! {
     );
 
     let mut adc = Adc::new(dp.ADC, Default::default());
-    let input = Keyboard::new(ADC7, ADC6);
+    let keyboard = Keyboard::new(ADC7, ADC6);
     let mut debounce = Debounce::default();
     let mut number_input = NumberInput::default();
 
@@ -491,7 +491,7 @@ fn main() -> ! {
     let mut state = State::EnterSignificant;
 
     loop {
-        let mut last_key_readout: Option<(usize, KeyReadout)> = None;
+        let mut last_key_readout: Option<KeyReadout> = None;
         for (mut io_select, ss) in io.iter_mut().zip(display.0.iter()) {
             ss.apply(&mut seg);
             io_select.set_on();
@@ -499,15 +499,13 @@ fn main() -> ! {
             io_select.set_off();
             seg.set_off();
             io_select.set_on();
-            if let Some(key_readout) = input.read(&mut adc) {
+            if let key_readout @ Some(_) = keyboard.read(&mut adc, io_select.display_no()) {
-                last_key_readout = Some((io_select.display_no(), key_readout));
+                last_key_readout = key_readout;
             }
             io_select.set_off();
         }
 
-        let key_press = last_key_readout
+        if let Some(key) = debounce.input(last_key_readout) {
-            .and_then(|(display_no, key_readout)| key_readout.to_keypress(display_no));
-        if let Some(key) = debounce.input(key_press) {
             ufmt::uwriteln!(&mut serial, "key: {:?} state: {:?}", key, state).unwrap_infallible();
             let res = match state {
                 State::EnterSignificant => match key {