gui to step through cpu instructions

Cargo.toml

@@ -8,7 +8,9 @@ edition = "2018"
 test = []
 
 [dependencies]
-log = "*"
-simple_logger = "*"
+log = "0.4.*"
+simple_logger = "1.3.*"
 phf = { version = "0.8", features = ['macros'] }
-failure = "*"
+failure = "0.1.*"
+piston_window = "0.105.*"
+piston2d-opengl_graphics = "0.70.*"

resources/fonts/LICENSE.txt

@@ -0,0 +1,94 @@
+Copyright (c) 2011, Cody "CodeMan38" Boisclair (cody@zone38.net),
+with Reserved Font Name "Press Start".
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.

src/cpu.rs

@@ -7,12 +7,12 @@ use crate::types::*;
 use log::{debug};
 
 pub struct Registers {
-    a: Byte,
-    x: Byte,
-    y: Byte,
-    sp: Byte,
-    pc: Addr,
-    flags: Byte 
+    pub a: Byte,
+    pub x: Byte,
+    pub y: Byte,
+    pub sp: Byte,
+    pub pc: Addr,
+    pub flags: Byte 
 }
 
 impl Registers {
@@ -37,17 +37,17 @@ impl Debug for Registers {
 }
 
 
-const CARRY: Byte = 1 << 0;
-const ZERO: Byte = 1 << 1;
-const IRQ: Byte = 1 << 2;
-const DECIMAL: Byte = 1 << 3;
-const BREAK: Byte = 1 << 4;
-const UNUSED: Byte = 1 << 5;
-const OVERFLOW: Byte = 1 << 6;
-const NEGATIVE: Byte = 1 << 7;
+pub const CARRY: Byte = 1 << 0;
+pub const ZERO: Byte = 1 << 1;
+pub const IRQ: Byte = 1 << 2;
+pub const DECIMAL: Byte = 1 << 3;
+pub const BREAK: Byte = 1 << 4;
+pub const UNUSED: Byte = 1 << 5;
+pub const OVERFLOW: Byte = 1 << 6;
+pub const NEGATIVE: Byte = 1 << 7;
 
 pub struct CPU {
-    regs: Registers,
+    pub regs: Registers,
     curr_op: Byte,  // current operation
     cycles: u8,  // number of clock clycles the CPU is ahead of global clock
 }
@@ -86,6 +86,11 @@ impl CPU {
         self.curr_op = 0x00;
     }
 
+    // True if the operation is not finished yet
+    pub fn is_ahead(&self) -> bool {
+        return self.cycles > 0;
+    }
+
     fn readb<T: Bus>(&self, bus: &T, addr: Addr) -> Byte {
         bus.readb(addr)
     }
@@ -122,7 +127,7 @@ impl CPU {
         } 
     }
 
-    fn get_flag(&mut self, flag: Byte) -> Byte {
+    pub fn get_flag(&self, flag: Byte) -> Byte {
         if self.regs.flags & flag > 0 {
             1
         } else {

src/main.rs

@@ -2,18 +2,27 @@
 #[macro_use] extern crate failure;
 extern crate simple_logger;
 extern crate phf;
+extern crate piston_window;
+
 
 #[allow(non_snake_case)]
 mod cpu;
 mod bus;
 mod types;
 
+use std::path::Path;
+use piston_window::*;
 use types::*;
-use cpu::CPU;
+use cpu::*;
 use bus::{MemoryBus, Bus};
+use opengl_graphics::OpenGL;
+use log::Level;
+use piston_window::Text;
 
 fn main() {
-    simple_logger::init().unwrap();
+    simple_logger::init_with_level(Level::Debug).unwrap();
+    let mut window: PistonWindow = WindowSettings::new("NESemu", [256*6, 240*4])
+        .exit_on_esc(true).graphics_api(OpenGL::V3_2).build().unwrap();
 
     let mut bus = MemoryBus::new();
 
@@ -30,12 +39,145 @@ fn main() {
     bus.writeb(0xfffc, offset as Byte);
     bus.writeb(0xfffc + 1, (offset >> 8) as Byte);
 
+    // Create and reset CPU 
     let mut cpu: CPU = CPU::new();
     cpu.reset(&bus);
-    for _ in 0..500+10 {
-        cpu.clock(&mut bus);
-        debug!("Mem: {} {} {}", bus.readb(0x00), bus.readb(0x01), bus.readb(0x02))
-    }
 
+    // Load font and start main loop
+    let font_path = Path::new("resources/fonts/PressStart2P.ttf");
+    let mut glyphs = window.load_font(font_path).unwrap();
+    while let Some(event) = window.next() {
+        if let Some(Button::Keyboard(key)) = event.press_args() {
+            if key == Key::C {  // advance one clock
+                cpu.clock(&mut bus);
+            } else if key == Key::Space {  // advance to next instruction
+                cpu.clock(&mut bus);
+                while cpu.is_ahead() {
+                    cpu.clock(&mut bus);
+                }
+            }
+        } 
+        render(&mut window, &event, &mut glyphs, &cpu, &bus);
+    }
+}
+
+fn render(window: &mut PistonWindow, event: &Event, glyphs: &mut Glyphs, cpu: &CPU, bus: &dyn Bus) {
+    window.draw_2d(event, |c, g, d| {
+        clear([0.0, 0.0, 1.0, 1.0], g);
+        render_cpu(&c, g, glyphs, cpu);
+        render_pc(&c, g, glyphs, cpu, bus);
+        glyphs.factory.encoder.flush(d); 
+    });
+}
+
+fn render_cpu(c: &Context, g: &mut G2d, glyphs: &mut Glyphs, cpu: &CPU) {
+        let font_size_pt = 36;
+        let color_white = [1.0; 4];
+        let color_red = [1.0, 0.0, 0.0, 1.0];
+        let color_green = [0.0, 1.0, 0.0, 1.0];
+        
+        let font_scale = 0.25;
+        let font_size_px = 12;
+
+        let line_distance = font_size_px as f64 * 0.5;
+        let x_dist = font_size_px as f64;
+
+        let flags_y = line_distance + font_size_px as f64;
+        let mut flags_x_offset = x_dist;
+        let mut transform = c.transform.trans(x_dist, flags_y).scale(font_scale, font_scale);
+        Text::new_color(color_white, font_size_pt).draw(
+                &"Flags:",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(300.0, 0.0);
+        Text::new_color(if cpu.get_flag(NEGATIVE) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"N",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(if cpu.get_flag(OVERFLOW) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"V",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(color_white, font_size_pt).draw(
+                &"-",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(if cpu.get_flag(BREAK) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"B",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(if cpu.get_flag(DECIMAL) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"D",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(if cpu.get_flag(IRQ) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"I",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(if cpu.get_flag(ZERO) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"Z",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        transform = transform.trans(72.0, 0.0);
+        Text::new_color(if cpu.get_flag(CARRY) == 1 { color_green} else { color_red } , font_size_pt).draw(
+                &"C",
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+
+        let cpu_register_texts = [
+            &format!("A: {:#x} ({})", cpu.regs.a, cpu.regs.a),
+            &format!("X: {:#x} ({})", cpu.regs.x, cpu.regs.y),
+            &format!("Y: {:#x} ({})", cpu.regs.y, cpu.regs.x),
+            &format!("Stack P: {:#x} ({})", cpu.regs.sp, cpu.regs.sp),
+            &format!("Program P: {:#x}", cpu.regs.pc),
+        ]; 
+
+        for (i, &text) in cpu_register_texts.iter().enumerate() {
+            let y_dist: f64 = (i+2) as f64*(line_distance + font_size_px as f64);
+            let transform = c.transform.trans(x_dist, y_dist).scale(font_scale, font_scale);
+            Text::new_color(color_white, font_size_pt).draw(
+                &text,
+                glyphs,
+                &c.draw_state,
+                transform,
+                g
+            );
+        }
+}
+
+fn render_pc(c: &Context, g: &mut G2d, glyphs: &mut Glyphs, cpu: &CPU, bus: &dyn Bus) {
 
 }