[cln] Code cleanup

Cleanup code
Add a offset delay timer

Cargo.lock

@@ -191,7 +191,7 @@ dependencies = [
 
 [[package]]
 name = "porcel8"
-version = "0.1.0"
+version = "0.1.1"
 dependencies = [
  "byteorder",
  "clap",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "porcel8"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

src/device/device.rs

@@ -37,28 +37,13 @@ impl Device {
 }
 
 impl Device {
-    const DEFAULT_FONT: [u8; 5 * 16] = [
-        0xF0, 0x90, 0x90, 0x90, 0xF0, // 0
-        0x20, 0x60, 0x20, 0x20, 0x70, // 1
-        0xF0, 0x10, 0xF0, 0x80, 0xF0, // 2
-        0xF0, 0x10, 0xF0, 0x10, 0xF0, // 3
-        0x90, 0x90, 0xF0, 0x10, 0x10, // 4
-        0xF0, 0x80, 0xF0, 0x10, 0xF0, // 5
-        0xF0, 0x80, 0xF0, 0x90, 0xF0, // 6
-        0xF0, 0x10, 0x20, 0x40, 0x40, // 7
-        0xF0, 0x90, 0xF0, 0x90, 0xF0, // 8
-        0xF0, 0x90, 0xF0, 0x10, 0xF0, // 9
-        0xF0, 0x90, 0xF0, 0x90, 0x90, // A
-        0xE0, 0x90, 0xE0, 0x90, 0xE0, // B
-        0xF0, 0x80, 0x80, 0x80, 0xF0, // C
-        0xE0, 0x90, 0x90, 0x90, 0xE0, // D
-        0xF0, 0x80, 0xF0, 0x80, 0xF0, // E
-        0xF0, 0x80, 0xF0, 0x80, 0x80  // F
-    ];
-    const FONT_DEFAULT_MEM_LOCATION_START: usize = 0x50;
     const FONT_HEIGHT: u16 = 5;
+    const FONT_DEFAULT_MEM_LOCATION_START: usize = 0x50;
     const FONT_DEFAULT_MEM_LOCATION_END: usize = 0x9F;
     const ROM_START: usize = 0x200;
+    
+    
+    
     pub fn cycle(&mut self) -> EmulatorResult<()> {
         self.device_keyboard.update_keyboard()?;
 
@@ -312,8 +297,26 @@ impl Device {
     }
 
     pub fn set_default_font(&mut self) {
+        const DEFAULT_FONT: [u8; Device::FONT_HEIGHT as usize * 16] = [
+            0xF0, 0x90, 0x90, 0x90, 0xF0, // 0
+            0x20, 0x60, 0x20, 0x20, 0x70, // 1
+            0xF0, 0x10, 0xF0, 0x80, 0xF0, // 2
+            0xF0, 0x10, 0xF0, 0x10, 0xF0, // 3
+            0x90, 0x90, 0xF0, 0x10, 0x10, // 4
+            0xF0, 0x80, 0xF0, 0x10, 0xF0, // 5
+            0xF0, 0x80, 0xF0, 0x90, 0xF0, // 6
+            0xF0, 0x10, 0x20, 0x40, 0x40, // 7
+            0xF0, 0x90, 0xF0, 0x90, 0xF0, // 8
+            0xF0, 0x90, 0xF0, 0x10, 0xF0, // 9
+            0xF0, 0x90, 0xF0, 0x90, 0x90, // A
+            0xE0, 0x90, 0xE0, 0x90, 0xE0, // B
+            0xF0, 0x80, 0x80, 0x80, 0xF0, // C
+            0xE0, 0x90, 0x90, 0x90, 0xE0, // D
+            0xF0, 0x80, 0xF0, 0x80, 0xF0, // E
+            0xF0, 0x80, 0xF0, 0x80, 0x80  // F
+        ];
         log::info!("Loaded default font from memory");
-        self.memory[Self::FONT_DEFAULT_MEM_LOCATION_START..=Self::FONT_DEFAULT_MEM_LOCATION_END].copy_from_slice(&Self::DEFAULT_FONT);
+        self.memory[Self::FONT_DEFAULT_MEM_LOCATION_START..=Self::FONT_DEFAULT_MEM_LOCATION_END].copy_from_slice(&DEFAULT_FONT);
     }
     /// load a rom from bytes
     pub fn load_rom(&mut self, rom: &[u8]) {

src/device/keyboard.rs

@@ -2,13 +2,11 @@ use std::sync::mpsc::TryRecvError;
 use crate::util::{EmulatorError, EmulatorResult};
 
 
-// display thread sends these to the device thread.
+/// An emulated keyboard that receives keyboard data as input
-
-// device thread updates on key up and down?
-
-
 pub struct Keyboard {
+    /// Current keyboard state
     bitflags: u16,
+    /// Receives keyboard events from main thread
     keyboard_event_receiver: std::sync::mpsc::Receiver<KeyboardEvent>,
 }
 
@@ -26,7 +24,8 @@ impl Keyboard {
         }
     }
 
-    /// Update keyboard based on pending keyboard events
+    /// Update keyboard based on pending keyboard events.
+    /// If no events are presents, it will return without any action.
     pub fn update_keyboard(&mut self) -> EmulatorResult<()> {
         loop {
             let keyboard_event_recv_res = self.keyboard_event_receiver.try_recv();
@@ -45,7 +44,6 @@ impl Keyboard {
         }
     }
 
-
     /// Query if key is down
     pub fn query_key_down(&self, key_num: u8) -> bool {
         (self.bitflags | 1 << key_num) == (1 << key_num)

src/main.rs

@@ -1,9 +1,8 @@
-use std::fs::File;
-use std::io::Read;
 use std::sync::{Arc, Mutex};
-use std::sync::mpsc::Receiver;
+use std::sync::mpsc::Sender;
 use std::thread;
-use std::time::Duration;
+use std::thread::JoinHandle;
+use std::time::{Duration};
 use clap::Parser;
 use log::LevelFilter;
 use sdl2::audio::{AudioQueue, AudioSpecDesired};
@@ -15,10 +14,10 @@ use sdl2::render::BlendMode;
 
 use sdl2::render::WindowCanvas;
 use simple_logger::SimpleLogger;
-use device::timer::DeviceTimerManager;
+
 use crate::args::Porcel8ProgramArgs;
 use crate::device::Device;
-use crate::device::keyboard::Keyboard;
+
 use crate::util::EmulatorResult;
 use crate::kb_map::get_key_index;
 use crate::sdl_adapters::sdl_audio_adapter::SdlAudioAdapter;
@@ -30,26 +29,26 @@ mod device;
 mod kb_map;
 mod util;
 mod sdl_adapters;
+mod rom;
 
 fn main() -> EmulatorResult<()> {
     SimpleLogger::new().with_level(LevelFilter::Info).env().init().unwrap();
-    let Porcel8ProgramArgs { filename, new_chip8_behaviour,draw_scale } = Porcel8ProgramArgs::parse();
+    let Porcel8ProgramArgs { filename, new_chip8_behaviour, draw_scale } = Porcel8ProgramArgs::parse();
+
     log::info!("Started emulator");
 
+    let (mut canvas, mut event_pump, audio_queue) = try_initiate_sdl(draw_scale)?;
 
-    let (mut canvas, mut event_pump,audio_queue) = try_initiate_sdl(draw_scale)?;
+    let (mut timer, mut sdl_aud_adapter) = SdlAudioAdapter::new_timers(SdlAudioAdapter::AUDIO_FREQUENCY, 0.85, audio_queue);
-
-    let (mut timer,mut sdl_aud_adapter) = SdlAudioAdapter::new_timers(440.0,0.85,audio_queue);
 
     let (frame_buffer_for_display, frame_buffer_for_device) = get_frame_buffer_references();
     let (sdl_kb_adapter, device_keyboard) = SdlKeyboardAdapter::new_keyboard();
 
-    let (device_termination_signal_sender, device_termination_signal_sender_receiver) = std::sync::mpsc::channel();
-    
     timer.start();
-    let compute_handle = thread::Builder::new().name("Compute".to_string()).spawn(move || {
+
-        do_device_loop(timer, frame_buffer_for_device, device_termination_signal_sender_receiver, device_keyboard, filename, new_chip8_behaviour);
+    let device = Device::new(timer, frame_buffer_for_device, device_keyboard, new_chip8_behaviour);
-    })?;
+
+    let (device_termination_signal_sender, compute_handle) = start_compute_thread(filename, device)?;
 
 
     let mut sdl_graphics_adapter = SdlGraphicsAdapter::new();
@@ -57,7 +56,11 @@ fn main() -> EmulatorResult<()> {
     canvas.set_draw_color(Color::BLACK);
     canvas.clear();
 
+    // Compute a frame time offset
+    // Thread will sleep for 60fps - (time spent computing)
+    let mut frame_timer = std::time::Instant::now();
     'running: loop {
+        let last_time = frame_timer.elapsed();
         for event in event_pump.poll_iter() {
             match event {
                 Event::Quit { .. } |
@@ -79,34 +82,35 @@ fn main() -> EmulatorResult<()> {
             }
         }
 
-
+        // lock and draw framebuffer
-        // The rest of the game loop goes here...
         {
             let lock = frame_buffer_for_display.lock()?;
             sdl_graphics_adapter.draw_screen(lock, &mut canvas)?;
         }
         canvas.present();
         sdl_aud_adapter.process_push_audio()?;
-        // 60fps - small offset to consider for cpu cycle time
+        let sleep_duration = SdlGraphicsAdapter::FRAME_RATE_TIMING - last_time;
-        thread::sleep(Duration::new(0, 1_000_000_000u32 / 60));
+        thread::sleep(sleep_duration);
+        frame_timer = std::time::Instant::now();
     }
 
     compute_handle.join().expect("Failed to close compute thread");
     Ok(())
 }
 
-fn do_device_loop(timer: DeviceTimerManager, frame_buffer: Arc<Mutex<Box<[bool; 2048]>>>, receiver: Receiver<()>, device_keyboard: Keyboard, rom_file_location_option: Option<String>, new_chip_behaviour: bool) {
+fn start_compute_thread(filename: Option<String>, mut device: Device) -> EmulatorResult<(Sender<()>, JoinHandle<()>)> {
-    let mut device = Device::new(timer, frame_buffer, device_keyboard, new_chip_behaviour);
     device.set_default_font();
 
-    if let Some(rom_file_location) = rom_file_location_option {
+    if let Some(rom_file_location) = filename {
-        let rom = load_rom(rom_file_location);
+        let rom = rom::load_rom(rom_file_location)?;
         device.load_rom(&rom);
-
     }
 
+    let (device_termination_signal_sender, device_termination_signal_sender_receiver) = std::sync::mpsc::channel();
+    let compute_handle = thread::Builder::new().name("Compute".to_string()).spawn(move || {
+
         loop {
-        let val = receiver.try_recv();
+            let val = device_termination_signal_sender_receiver.try_recv();
             if let Ok(()) = val {
                 break;
             } else if let Err(std::sync::mpsc::TryRecvError::Disconnected) = val {
@@ -116,6 +120,8 @@ fn do_device_loop(timer: DeviceTimerManager, frame_buffer: Arc<Mutex<Box<[bool;
             // Put a bit of delay to slow down execution
             thread::sleep(Duration::from_millis(2))
         }
+    })?;
+    Ok((device_termination_signal_sender, compute_handle))
 }
 
 
@@ -125,15 +131,10 @@ fn get_frame_buffer_references() -> (Arc<Mutex<Box<[bool; 2048]>>>, Arc<Mutex<Bo
     (arc, arc2)
 }
 
-const ROM_SIZE: usize = 4096 - 0x200;
+/// Initiate SDL resources:
-
+/// 1. A window canvas for drawing
-fn load_rom(rom_file_location: String) -> [u8; ROM_SIZE] {
+/// 2. An event pump for use as an event loop,
-    let mut rom_slice = [0u8; ROM_SIZE];
+/// 3. An Audio queue for sound
-    let mut file = File::open(rom_file_location).expect("could not open");
-    file.read(&mut rom_slice).expect("Unwrap");
-    rom_slice
-}
-
 fn try_initiate_sdl(draw_scale: f32) -> EmulatorResult<(WindowCanvas, EventPump, AudioQueue<f32>)> {
     let sdl_context = sdl2::init().unwrap();
     let video_subsystem = sdl_context.video().unwrap();
@@ -144,7 +145,7 @@ fn try_initiate_sdl(draw_scale: f32) -> EmulatorResult<(WindowCanvas, EventPump,
         freq: Some(SdlAudioAdapter::SAMPLING_FREQ),
     };
 
-    let audio_queue = audio_subsystem.open_queue::<f32,_>(None, &wanted_spec)?;
+    let audio_queue = audio_subsystem.open_queue::<f32, _>(None, &wanted_spec)?;
 
     let window_width = (Device::FRAME_BUFFER_WIDTH as f32 * draw_scale) as u32;
     let window_height = (Device::FRAME_BUFFER_HEIGHT as f32 * draw_scale) as u32;
@@ -160,7 +161,7 @@ fn try_initiate_sdl(draw_scale: f32) -> EmulatorResult<(WindowCanvas, EventPump,
     canvas.clear();
     canvas.present();
     let event_pump = sdl_context.event_pump()?;
-    Ok((canvas, event_pump,audio_queue))
+    Ok((canvas, event_pump, audio_queue))
 }
 
 

src/rom.rs

@@ -0,0 +1,12 @@
+use std::fs::File;
+use std::io::Read;
+use crate::util::EmulatorResult;
+
+pub const ROM_SIZE: usize = 4096 - 0x200;
+
+pub fn load_rom(rom_file_location: String) -> EmulatorResult<[u8; ROM_SIZE]> {
+    let mut rom_slice = [0u8; ROM_SIZE];
+    let mut file = File::open(rom_file_location)?;
+    file.read(&mut rom_slice)?;
+    Ok(rom_slice)
+}

src/sdl_adapters/sdl_audio_adapter.rs

@@ -16,6 +16,7 @@ pub struct SdlAudioAdapter {
 impl SdlAudioAdapter {
     /// Number of samples per second
     pub const SAMPLING_FREQ:i32 = 15360;
+    pub const AUDIO_FREQUENCY: f32 = 440.0;
     pub const SAMPLES_PER_FRAME: usize = (Self::SAMPLING_FREQ as usize / 60) * 2;
     pub fn new_timers(freq: f32,
                  volume: f32,

src/sdl_adapters/sdl_graphics_adapter.rs

@@ -1,15 +1,16 @@
 use std::sync::MutexGuard;
+use std::time::Duration;
 use sdl2::pixels::PixelFormatEnum;
 use sdl2::render::{TextureAccess, WindowCanvas};
 use crate::device::Device;
 use crate::util::EmulatorResult;
 
-#[derive(Debug)]
 pub struct SdlGraphicsAdapter {
     rgb_frame_buffer: Vec<u8>,
 }
 
 impl SdlGraphicsAdapter {
+    pub const FRAME_RATE_TIMING: Duration = Duration::new(0, 1_000_000_000u32 / 60);
     pub const RGB_COMPONENTS: usize = 3;
     pub const RGB_FRAMEBUFFER_SIZE: usize = Self::RGB_COMPONENTS * Device::FRAME_BUFFER_SIZE;
     pub fn new() -> SdlGraphicsAdapter {
@@ -18,7 +19,7 @@ impl SdlGraphicsAdapter {
             rgb_frame_buffer
         }
     }
-    pub fn draw_screen(&mut self, frame_buffer: MutexGuard<Box<[bool; Device::FRAME_BUFFER_SIZE]>>, window_canvas: &mut WindowCanvas) ->EmulatorResult<()> {
+    pub fn draw_screen(&mut self, frame_buffer: MutexGuard<Box<[bool; Device::FRAME_BUFFER_SIZE]>>, window_canvas: &mut WindowCanvas) -> EmulatorResult<()> {
         for (i, pixel) in frame_buffer.iter().enumerate() {
             let col_component = if *pixel { 0xff } else { 0 };
             self.rgb_frame_buffer[3 * i] = col_component;