chore: remove useless default implementations

src/apu.rs

@@ -211,8 +211,8 @@ impl Apu {
         self.ch4.poly = Default::default();
         self.ch4.freq = Default::default();
 
-        self.ctrl.channel = Default::default();
+        self.ctrl.channel = ChannelControl(0);
-        self.ctrl.out = Default::default();
+        self.ctrl.out = SoundOutput(0);
 
         // Disable the Channels
         self.ch1.enabled = Default::default();
@@ -344,7 +344,7 @@ impl Apu {
     }
 }
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub(crate) struct SoundControl {
     /// 0xFF24 | NR50 - Channel Control
     channel: ChannelControl,
@@ -354,6 +354,16 @@ pub(crate) struct SoundControl {
     enabled: bool,
 }
 
+impl Default for SoundControl {
+    fn default() -> Self {
+        Self {
+            channel: ChannelControl(0),
+            out: SoundOutput(0),
+            enabled: Default::default(),
+        }
+    }
+}
+
 impl SoundControl {
     /// 0xFF24 | NR50 - Channel Control
     pub(crate) fn channel(&self) -> u8 {

src/apu/types.rs

@@ -416,12 +416,6 @@ pub(super) mod common {
         }
     }
 
-    impl Default for WavePattern {
-        fn default() -> Self {
-            Self::OneEighth // Rationale: OneEighth is 0x00
-        }
-    }
-
     impl From<WavePattern> for u8 {
         fn from(pattern: WavePattern) -> Self {
             pattern as Self
@@ -479,12 +473,6 @@ impl Clone for SoundOutput {
     }
 }
 
-impl Default for SoundOutput {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for SoundOutput {
     fn from(byte: u8) -> Self {
         Self(byte)
@@ -523,12 +511,6 @@ impl Clone for ChannelControl {
     }
 }
 
-impl Default for ChannelControl {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for ChannelControl {
     fn from(byte: u8) -> Self {
         Self(byte)

src/cartridge.rs

@@ -297,7 +297,7 @@ struct RtClock {
 
 impl RtClock {
     fn inc_day(&mut self) {
-        // TODO: Figure out order of operations, the brackets are a bit too defenseive here
+        // TODO: Figure out order of operations, the brackets are a bit too defensive here
         let days: u16 = (((self.day_high.ninth() as u16) << 8) | self.day_low as u16) + 1;
 
         if days > 0x1FF {

src/cpu.rs

@@ -19,9 +19,9 @@ impl Cpu {
         Self {
             bus: Bus::with_boot(rom),
             reg: Default::default(),
-            flags: Default::default(),
+            flags: Flags(0),
-            ime: Default::default(),
+            ime: ImeState::Disabled,
-            state: Default::default(),
+            state: State::Execute,
         }
     }
 
@@ -238,12 +238,6 @@ enum State {
     // Stop,
 }
 
-impl Default for State {
-    fn default() -> Self {
-        Self::Execute
-    }
-}
-
 impl Cpu {
     pub(crate) fn set_register(&mut self, register: Register, value: u8) {
         use Register::*;
@@ -437,12 +431,6 @@ impl Clone for Flags {
     }
 }
 
-impl Default for Flags {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl Display for Flags {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
         if self.z() {
@@ -497,9 +485,3 @@ pub(crate) enum ImeState {
     Pending,
     Enabled,
 }
-
-impl Default for ImeState {
-    fn default() -> Self {
-        Self::Disabled
-    }
-}

src/interrupt.rs

@@ -1,11 +1,20 @@
 use bitfield::bitfield;
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub(crate) struct Interrupt {
     pub(crate) flag: InterruptFlag,
     pub(crate) enable: InterruptEnable,
 }
 
+impl Default for Interrupt {
+    fn default() -> Self {
+        Self {
+            flag: InterruptFlag(0),
+            enable: InterruptEnable(0),
+        }
+    }
+}
+
 bitfield! {
    pub struct InterruptEnable(u8);
     impl Debug;
@@ -23,12 +32,6 @@ impl Clone for InterruptEnable {
     }
 }
 
-impl Default for InterruptEnable {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for InterruptEnable {
     fn from(byte: u8) -> Self {
         Self(byte)
@@ -58,12 +61,6 @@ impl Clone for InterruptFlag {
     }
 }
 
-impl Default for InterruptFlag {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for InterruptFlag {
     fn from(byte: u8) -> Self {
         Self(byte)

src/ppu.rs

@@ -470,10 +470,10 @@ impl Default for Ppu {
             dot: Default::default(),
             frame_buf: Box::new([0; GB_WIDTH * GB_HEIGHT * 4]),
             int: Default::default(),
-            ctrl: Default::default(),
+            ctrl: LCDControl(0),
             monochrome: Default::default(),
             pos: Default::default(),
-            stat: Default::default(),
+            stat: LCDStatus(0x80), // bit 7 is always 1
             oam: Default::default(),
             scan_dot: Default::default(),
             fetch: Default::default(),
@@ -528,7 +528,7 @@ pub(crate) struct ScreenPosition {
     pub(crate) window_x: u8,
 }
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub(crate) struct Monochrome {
     /// 0xFF47 | BGP - Background Palette Data
     pub(crate) bg_palette: BackgroundPalette,
@@ -538,6 +538,16 @@ pub(crate) struct Monochrome {
     pub(crate) obj_palette_1: ObjectPalette,
 }
 
+impl Default for Monochrome {
+    fn default() -> Self {
+        Self {
+            bg_palette: BackgroundPalette(0),
+            obj_palette_0: ObjectPalette(0),
+            obj_palette_1: ObjectPalette(0),
+        }
+    }
+}
+
 #[derive(Debug)]
 pub(crate) struct ObjectAttrTable {
     buf: Box<[u8; OAM_SIZE]>,
@@ -575,7 +585,7 @@ impl Default for ObjectAttrTable {
     }
 }
 
-#[derive(Debug, Clone, Copy, Default)]
+#[derive(Debug, Clone, Copy)]
 struct ObjectAttr {
     y: u8,
     x: u8,
@@ -836,7 +846,7 @@ struct BgPixelProperty {
     shade_id: u8,
 }
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 struct ObjPixelProperty {
     shade_id: u8,
     palette_kind: ObjectPaletteKind,

src/ppu/dma.rs

@@ -1,6 +1,6 @@
 use crate::Cycle;
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub(crate) struct DirectMemoryAccess {
     pub(crate) state: DmaState,
     cycle: Cycle,
@@ -8,6 +8,16 @@ pub(crate) struct DirectMemoryAccess {
     pub(crate) start: DmaAddress,
 }
 
+impl Default for DirectMemoryAccess {
+    fn default() -> Self {
+        Self {
+            state: DmaState::Disabled,
+            cycle: Default::default(),
+            start: Default::default(),
+        }
+    }
+}
+
 impl DirectMemoryAccess {
     pub(crate) fn tick(&mut self) -> Option<(u16, u16)> {
         match self.state {
@@ -69,12 +79,6 @@ pub(crate) enum DmaState {
     Transferring,
 }
 
-impl Default for DmaState {
-    fn default() -> Self {
-        Self::Disabled
-    }
-}
-
 #[derive(Debug, Clone, Copy, Default)]
 pub(crate) struct DmaAddress(Option<u16>);
 

src/ppu/types.rs

@@ -29,12 +29,6 @@ impl Clone for LCDStatus {
     }
 }
 
-impl Default for LCDStatus {
-    fn default() -> Self {
-        Self(0x80) // bit 7 is always 1
-    }
-}
-
 impl From<LCDStatus> for u8 {
     fn from(status: LCDStatus) -> Self {
         status.0
@@ -67,12 +61,6 @@ impl From<PpuMode> for u8 {
     }
 }
 
-impl Default for PpuMode {
-    fn default() -> Self {
-        Self::HBlank
-    }
-}
-
 bitfield! {
     pub struct LCDControl(u8);
     impl Debug;
@@ -93,12 +81,6 @@ impl Clone for LCDControl {
     }
 }
 
-impl Default for LCDControl {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for LCDControl {
     fn from(byte: u8) -> Self {
         Self(byte)
@@ -142,12 +124,6 @@ impl From<TileMapAddress> for u8 {
     }
 }
 
-impl Default for TileMapAddress {
-    fn default() -> Self {
-        Self::X9800
-    }
-}
-
 #[derive(Debug, Clone, Copy)]
 pub enum TileDataAddress {
     X8800 = 0,
@@ -170,12 +146,6 @@ impl From<TileDataAddress> for u8 {
     }
 }
 
-impl Default for TileDataAddress {
-    fn default() -> Self {
-        Self::X8800
-    }
-}
-
 #[derive(Debug, Clone, Copy)]
 pub enum ObjectSize {
     Eight = 0,
@@ -209,12 +179,6 @@ impl From<ObjectSize> for u8 {
     }
 }
 
-impl Default for ObjectSize {
-    fn default() -> Self {
-        Self::Eight
-    }
-}
-
 bitfield! {
     pub struct BackgroundPalette(u8);
     impl Debug;
@@ -243,12 +207,6 @@ impl Clone for BackgroundPalette {
     }
 }
 
-impl Default for BackgroundPalette {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for BackgroundPalette {
     fn from(byte: u8) -> Self {
         Self(byte)
@@ -288,12 +246,6 @@ impl Clone for ObjectPalette {
     }
 }
 
-impl Default for ObjectPalette {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for ObjectPalette {
     fn from(byte: u8) -> Self {
         Self(byte)
@@ -361,24 +313,12 @@ impl From<ObjectFlags> for u8 {
     }
 }
 
-impl Default for ObjectFlags {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 #[derive(Debug, Clone, Copy)]
 pub enum ObjectPaletteKind {
     Zero = 0,
     One = 1,
 }
 
-impl Default for ObjectPaletteKind {
-    fn default() -> Self {
-        Self::Zero
-    }
-}
-
 impl From<u8> for ObjectPaletteKind {
     fn from(byte: u8) -> Self {
         match byte & 0b01 {
@@ -417,12 +357,6 @@ impl From<RenderPriority> for u8 {
     }
 }
 
-impl Default for RenderPriority {
-    fn default() -> Self {
-        Self::Object
-    }
-}
-
 #[derive(Debug, Clone, Copy)]
 pub enum GrayShade {
     White = 0,
@@ -442,12 +376,6 @@ impl GrayShade {
     }
 }
 
-impl Default for GrayShade {
-    fn default() -> Self {
-        Self::White
-    }
-}
-
 impl From<u8> for GrayShade {
     fn from(byte: u8) -> Self {
         match byte & 0b11 {

src/serial.rs

@@ -1,6 +1,6 @@
 use bitfield::bitfield;
 
-#[derive(Debug, Default)]
+#[derive(Debug)]
 pub(crate) struct Serial {
     /// 0xFF01 | SB - Serial Transfer Data
     pub(crate) next: u8,
@@ -8,6 +8,15 @@ pub(crate) struct Serial {
     pub(crate) ctrl: SerialControl,
 }
 
+impl Default for Serial {
+    fn default() -> Self {
+        Self {
+            next: Default::default(),
+            ctrl: SerialControl(0),
+        }
+    }
+}
+
 bitfield! {
     pub struct SerialControl(u8);
     impl Debug;
@@ -23,12 +32,6 @@ impl Clone for SerialControl {
     }
 }
 
-impl Default for SerialControl {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for SerialControl {
     fn from(byte: u8) -> Self {
         Self(byte)
@@ -47,12 +50,6 @@ enum ShiftClock {
     Internal = 1,
 }
 
-impl Default for ShiftClock {
-    fn default() -> Self {
-        Self::External
-    }
-}
-
 impl From<u8> for ShiftClock {
     fn from(byte: u8) -> Self {
         match byte & 0b01 {
@@ -69,12 +66,6 @@ enum ClockSpeed {
     Fast = 1,
 }
 
-impl Default for ClockSpeed {
-    fn default() -> Self {
-        Self::Normal
-    }
-}
-
 impl From<u8> for ClockSpeed {
     fn from(byte: u8) -> Self {
         match byte & 0b01 {

src/timer.rs

@@ -106,7 +106,7 @@ impl Timer {
 impl Default for Timer {
     fn default() -> Self {
         Self {
-            ctrl: Default::default(),
+            ctrl: TimerControl(0),
             counter: 0,
             modulo: 0,
             divider: 0,
@@ -157,12 +157,6 @@ impl Clone for TimerControl {
     }
 }
 
-impl Default for TimerControl {
-    fn default() -> Self {
-        Self(0)
-    }
-}
-
 impl From<u8> for TimerControl {
     fn from(byte: u8) -> Self {
         Self(byte)