adds more test roms

adds list of test roms and ability to load as desired
passes the Corax+ opcode test now

.idea/trevors_chip8_toy.iml

@@ -1,13 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="EMPTY_MODULE" version="4">
-  <component name="NewModuleRootManager">
-    <content url="file://$MODULE_DIR$">
-      <sourceFolder url="file://$MODULE_DIR$/chip8_core/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/chip8_toy/src" isTestSource="false" />
-      <sourceFolder url="file://$MODULE_DIR$/emma/src" isTestSource="false" />
-      <excludeFolder url="file://$MODULE_DIR$/target" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>

emma/src/bin/emmagui.rs

@@ -1,3 +1,6 @@
+use std::default::Default;
+use std::fs::DirEntry;
+use std::time::Instant;
 use emmaemu::{
     chip8::computer::Chip8Computer,
     constants::{CHIP8_MEMORY_SIZE, CHIP8_VIDEO_HEIGHT, CHIP8_VIDEO_WIDTH},
@@ -11,53 +14,61 @@ use support::emmagui_support::EmmaGui;
 mod support;
 
 
-fn hello_world_window(ui: &Ui) {
-
-    let mut value = 1;
-    let choices = ["test test this is 1", "test test this is 2"];
-    ui.window("EmmaGui")
-        .size([300.0, 110.0], Condition::FirstUseEver)
-        .build(|| {
-            ui.text_wrapped("Hello world!");
-            ui.text_wrapped("こんにちは世界！");
-            if ui.button(choices[value]) {
-                value += 1;
-                value %= 2;
-            }
-
-            ui.button("This...is...imgui-rs!");
-            ui.separator();
-            let mouse_pos = ui.io().mouse_pos;
-            ui.text(format!(
-                "Mouse Position: ({:.1},{:.1})",
-                mouse_pos[0], mouse_pos[1]
-            ));
-        });
-}
-
-#[derive(Copy, Clone)]
 struct UiState {
     pub show_registers: bool,
     pub show_memory: bool,
-    pub show_video: bool
+    pub show_video: bool,
+    pub filename_to_load: String,
+   pub on_colour: ImColor32,
+   pub off_colour: ImColor32,
+    pub is_running: bool,
+    pub frame_time: f32
+}
+
+impl Clone for UiState {
+    fn clone(&self) -> Self {
+        UiState {
+            show_registers: self.show_registers,
+            show_memory: self.show_memory,
+            show_video: self.show_video,
+            filename_to_load: self.filename_to_load.to_string(),
+            on_colour: self.on_colour,
+            off_colour: self.off_colour,
+            is_running: self.is_running,
+            frame_time: self.frame_time
+        }
+    }
 }
 
 impl Default for UiState {
     fn default() -> Self {
         UiState {
-            show_registers: true,
+            show_registers: false,
-            show_memory: true,
+            show_memory: false,
-            show_video: true
+            show_video: true,
+            filename_to_load: String::new(),
+            on_colour: ImColor32::from_rgb(0xff, 0xff, 0x00),
+            off_colour: ImColor32::from_rgb(0x00, 0xff, 0xff),
+            is_running: false,
+            frame_time: 32.0
         }
     }
 }
 
-
 fn main() {
     pretty_env_logger::init();
     let mut system = Chip8Computer::default();
     let mut ui_state = UiState::default();
+    let mut last_tick_time = Instant::now();
+
     support::simple_init(file!(), move |_, ui| {
+        let current_time = Instant::now();
+        let time_since_last_tick = current_time.duration_since(last_tick_time).as_millis();
+        if ui_state.is_running && time_since_last_tick > ui_state.frame_time as u128 {
+            system.step_system();
+            last_tick_time = current_time;
+        }
+
         EmmaGui::system_controls(&mut system, &mut ui_state, ui);
 
         if ui_state.show_registers {
@@ -65,16 +76,12 @@ fn main() {
         }
 
         if ui_state.show_video {
-            EmmaGui::video_display(&system, ui);
+            EmmaGui::video_display(&system, &ui_state, ui);
         }
 
         if ui_state.show_memory {
             let active_instruction = system.registers.peek_pc();
             EmmaGui::hex_memory_display(system.memory.clone(), (0x100, 0x10), active_instruction as i16, ui);
         }
-      //  EmmaGui::system_memory_render(system.memory, ui);
-
-      //  system.memory.gui_render(ui);
-
     });
 }

emma/src/bin/support/emmagui_support.rs

@@ -1,29 +1,51 @@
 use std::fs::File;
 use std::io::Read;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use std::thread::sleep;
 use std::time::Duration;
 use imgui::{Condition, ImColor32, Ui};
+use log::debug;
 use emmaemu::chip8::computer::Chip8Computer;
 use emmaemu::chip8::system_memory::Chip8SystemMemory;
 use emmaemu::constants::{CHIP8_VIDEO_HEIGHT, CHIP8_VIDEO_WIDTH};
 use crate::UiState;
 
 
-pub struct EmmaGui  {
+pub struct EmmaGui {}
-}
 
 const CELL_WIDTH: i32 = 5i32;
 const CELL_HEIGHT: i32 = 5i32;
 
+struct GuiFileList {}
+
+impl GuiFileList {
+    pub fn display_path(root: PathBuf, selected_filename: &String, ui: &Ui) -> String {
+        let mut working_filename = selected_filename.clone();
+        ui.text(format!("Displaying {}", root.to_str().unwrap_or("Unable to parse path")));
+        for (index, entry) in std::fs::read_dir(root.as_path()).unwrap().enumerate() {
+            let filename = entry.unwrap().file_name();
+            let filename = filename.to_str().unwrap();
+            let mut working_select = ui.selectable_config(format!("{}", filename));
+            if filename == selected_filename {
+                working_select = working_select.selected(true);
+            }
+            if working_select.build() {
+                debug!("SELECTED {index} / {filename}");
+                working_filename = filename.to_string();
+            };
+        }
+        working_filename
+    }
+}
+
+
 impl EmmaGui {
-    pub fn video_display(system_to_control: &Chip8Computer, ui: &Ui) {
+    pub fn video_display(system_to_control: &Chip8Computer, gui_state: &UiState, ui: &Ui) {
         // draw area size
         let draw_area_size = ui.io().display_size;
         let cell_width = ((draw_area_size[0] as i32 / 64) * 6) / 10;
         let cell_height = ((draw_area_size[1] as i32 / 32) * 6) / 10;
 
-
         ui.window(format!("Display {cell_width}x{cell_height}"))
             .size([300.0, 300.0], Condition::FirstUseEver)
             .build(|| {
@@ -39,9 +61,9 @@ impl EmmaGui {
                         let memory_offset = (current_row * 64 + current_column) as u16;
                         let to_render = system_to_control.video_memory.peek(memory_offset);
                         let color: ImColor32 = if to_render {
-                            ImColor32::from_rgb(0xff, 0x00, 0x00)
+                            gui_state.on_colour
                         } else {
-                            ImColor32::from_rgb(0x00, 0x00, 0xff)
+                            gui_state.off_colour
                         };
                         fg.add_rect_filled_multicolor(current_origin, current_limit, color, color, color, color);
                     }
@@ -50,40 +72,59 @@ impl EmmaGui {
     }
     pub fn system_controls(system_to_control: &mut Chip8Computer, gui_state: &mut UiState, ui: &Ui) {
         ui.window("!!!! CONTROLS !!!!")
-            .size([200.0, 200.0], Condition::FirstUseEver)
+            .size([345.0, 200.0], Condition::FirstUseEver)
             .build(|| {
-                ui.text("Computer Controls");
+                /* ROM Lister */
-
+                let new_filename = GuiFileList::display_path(PathBuf::from("resources/roms"), &gui_state.filename_to_load, ui);
-                if ui.button("Step") {
+                if !new_filename.is_empty() {
-                    system_to_control.step_system();
+                    if new_filename != gui_state.filename_to_load {
-                };
+                        println!("NEW FILENAME SELECTED -> {new_filename}");
+                        gui_state.filename_to_load = new_filename;
+                    }
                     if ui.button("Load Program") {
                         let mut buffer = Vec::new();
 
-                    println!("PREPARING TO LOAD 1-chip8-logo.ch8");
+                        println!("PREPARING TO LOAD {}", gui_state.filename_to_load);
                         // let mut input_file = File::open(Path::new("./1-chip8-logo.ch8")).expect("put 1-chip8-logo.ch8 in this directory");
-                    let mut input_file = File::open(Path::new("./coraxhard.ch8")).expect("put 1-chip8-logo.ch8 in this directory");
+                        let mut input_file = File::open(Path::new(&("resources/roms/".to_string() + &gui_state.filename_to_load))).expect("put 1-chip8-logo.ch8 in this directory");
                         input_file.read_to_end(&mut buffer).expect("unable to read file");
                         system_to_control.load_bytes_to_memory(0x200, buffer.into());
                     }
+                }
+                ui.separator();
+                if ui.button("Step") {
+                    system_to_control.step_system();
+                };
+                if ui.button("Run") {
+                    gui_state.is_running = true;
+                    println!("STARTING THE SYSTEM");
+                }
+                if ui.button("Stop") {
+                    gui_state.is_running = false;
+                    println!("STOPPING THE SYSTEM");
+                }
+                ui.same_line();
                 if ui.button("Reset") {
                     *system_to_control = Chip8Computer::new();
                 }
-
                 if ui.button("Dump Video Memory") {
                     println!("{}", system_to_control.dump_video_to_string());
                 }
+                ui.same_line();
                 if ui.button("Dump Keypad State") {
                     println!("{}", system_to_control.dump_keypad_to_string());
                 }
+                ui.same_line();
                 if ui.button("Dump Registers") {
                     println!("{}", system_to_control.dump_registers_to_string());
                 }
+                ui.separator();
 
                 ui.checkbox("Show Memory", &mut gui_state.show_memory);
+                ui.same_line();
                 ui.checkbox("Show Video", &mut gui_state.show_video);
+                ui.same_line();
                 ui.checkbox("Show Registers", &mut gui_state.show_registers);
-
             });
     }
 
@@ -114,6 +155,7 @@ impl EmmaGui {
         let cols = position.1;
         ui.window("System Memory")
             .size([400.0, 300.0], Condition::FirstUseEver)
+            .position([500.0, 300.0], Condition::Always)
             .build(|| {
                 let mut current_x_hover: i32 = 0;
                 let mut current_y_hover: i32 = 0;

emma/src/chip8/instructions.rs

@@ -496,24 +496,38 @@ impl Chip8CpuInstructions {
             }
             // 0x8xy1 Set Vx = Vx OR Vy
             Chip8CpuInstructions::OrVxVy(x, y) => {
-                input.registers.poke(*x as u8, input.registers.peek(*x as u8) | input.registers.peek(*y as u8));
+                // shift them to 16 bit
+                let working_16_x = input.registers.peek(*x as u8) as u16;
+                let working_16_y = input.registers.peek(*y as u8) as u16;
+                // OR them
+                let working_16_or = working_16_x | working_16_y;
+                // shift them back to 8 bit.
+                let to_set = working_16_or as u8;
+                input.registers.poke(*x as u8, to_set);
                 debug!("OrVxVy [0x{x:1x}] [0x{y:1x}]")
             }
             // 0x8xy2 Set Vx = Vx AND Vy
             Chip8CpuInstructions::AndVxVy(x, y) => {
-                input.registers.poke(*x as u8, input.registers.peek(*x as u8) & input.registers.peek(*y as u8));
+                let lhs_16 = input.registers.peek(*x as u8) as u16;
-                debug!("AndVxVy [0x{x:1x}] [0x{y:1x}]");
+                let rhs_16 = input.registers.peek(*y as u8) as u16;
+                let and_16 = lhs_16 & rhs_16;
+
+                input.registers.poke(*x as u8, and_16 as u8);
+                debug!("AndVxVy [0x{x:02x}] [0x{y:02x}] [0b{and_16:08b}");
             }
             // 0x8xy3 Set Vx = Vx XOR Vy
             Chip8CpuInstructions::XorVxVy(x, y) => {
-                input.registers.poke(*x as u8, input.registers.peek(*x as u8) ^ input.registers.peek(*y as u8));
+                let lhs_16 = input.registers.peek(*x as u8) as u16;
+                let rhs_16 = input.registers.peek(*y as u8) as u16;
+                let xor_16 = lhs_16 ^ rhs_16;
+                input.registers.poke(*x as u8, xor_16 as u8);
             }
             // 0x8xy4 Set Vx = Vx + Vy (SET VF on Carry)
             Chip8CpuInstructions::AddVxVy(x, y) => {
-                let lhs = input.registers.peek(*x as u8);
+                let lhs = input.registers.peek(*x as u8) as i16;
-                let rhs = input.registers.peek(*y as u8);
+                let rhs = input.registers.peek(*y as u8) as i16;
-                let working = (lhs as i16 + rhs as i16) as i16;
+                let working = lhs + rhs;
-                if working > 255 {
+                if working > 0xff {
                     input.registers.poke(0xf, 0x01);
                 }
                 input.registers.poke(*x as u8, working as u8);
@@ -759,11 +773,14 @@ impl Chip8CpuInstructions {
             Chip8CpuInstructions::LdIVx(x) => {
                 // Store registers V0 through Vx in memory starting at location I.
                 //
-                // The interpreter copies the values of registers V0 through Vx into memory, starting at the address in I.
+                // The interpreter copies the values of registers V0 through Vx into memory,
+                // starting at the address in I.
+                let num_loops = x;
                 let offset = input.registers.peek_i();
-                for i in 0..*x {
+                for i in 0..=*x {
                     input.memory.poke(offset + i, input.registers.peek(i as u8));
                 }
+                input.registers.poke_i(offset + 1);
             }
             Chip8CpuInstructions::LdVxI(x) => {
                 // Read registers V0 through Vx from memory starting at location I.
@@ -771,14 +788,14 @@ impl Chip8CpuInstructions {
                 // The interpreter reads values from memory starting at location I into registers V0 through Vx.
                 let offset = input.registers.peek_i();
                 debug!("STARTING TO READ AT {offset:03x}");
-                let num_loops = input.registers.peek(*x as u8);
+                let num_loops = x + 1;
-                debug!("WILL READ {num_loops:x} BYTES");
+                println!("WILL READ {num_loops:x} BYTES");
                 for index in 0..num_loops {
                     let src_value = input.memory.peek(index as u16 + offset);
-
+                    input.registers.poke(index as u8, src_value);
-                    input.registers.poke(index, src_value);
+                    println!("POKING Register 0x{index:02x} with 0x{src_value:04x} using offset 0x{offset:04x}");
-                    debug!("POKING {index} with {src_value}");
                 }
+         input.registers.poke_i(offset + 1);
             }
             Chip8CpuInstructions::XXXXERRORINSTRUCTION => {}
         };
@@ -896,8 +913,12 @@ mod test {
         let mut x = Chip8Computer::new();
         Chip8CpuInstructions::SysAddr(0).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0);
+
+        let mut x = Chip8Computer::new();
         Chip8CpuInstructions::SysAddr(0xFA0).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0xFA0);
+
+        let mut x = Chip8Computer::new();
         Chip8CpuInstructions::SysAddr(0x0AF).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0x0AF);
     }
@@ -908,6 +929,8 @@ mod test {
         let mut x = Chip8Computer::new();
         Chip8CpuInstructions::JpAddr(0).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0);
+
+        let mut x = Chip8Computer::new();
         Chip8CpuInstructions::JpAddr(0xABC).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0xABC);
     }
@@ -919,10 +942,10 @@ mod test {
         let mut x = Chip8Computer::new();
         Chip8CpuInstructions::LdVxByte(1, 0x12).execute(&mut x);
         assert_eq!(x.registers.peek(1), 0x12);
-        assert_eq!(x.registers.peek_pc(), 0x202);
+
+        let mut x = Chip8Computer::new();
         Chip8CpuInstructions::LdVxByte(2, 0x21).execute(&mut x);
         assert_eq!(x.registers.peek(2), 0x21);
-        assert_eq!(x.registers.peek_pc(), 0x204);
     }
 
     #[test]
@@ -933,69 +956,41 @@ mod test {
 
         // test setup: Load value 0x84 into V1
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(1, 0x84).execute(&mut x);
+        x.registers.poke(0x1, 0x84);
-        Chip8CpuInstructions::SeVxByte(1, 0x84).execute(&mut x);
+        Chip8CpuInstructions::SeVxByte(1, 0x48).execute(&mut x);
-        // we should be 6 instructions past.
-        // 2 for the LDVXBYTE
-        // 2 for the SEVXBYTE
-        // 2 for skipping.
-        assert_eq!(x.registers.peek_pc(), 0x206);
-    }
-
-    #[test]
-    fn sevxbyte_nomatch_test() {
-        // 0x3xkk Skip next instruction if Vx = kk.
-        // The interpreter compares register Vx to kk,
-        // and if they are equal, increments the program counter by 2.
-
-        // test setup: Load value 0x84 into V1
-        let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x01, 0x84).execute(&mut x);
-        // PC will be 2 bytes past as we executed an instruction...
         assert_eq!(x.registers.peek_pc(), 0x202);
 
-        Chip8CpuInstructions::SeVxByte(1, 0x48).execute(&mut x);
+        let mut x = Chip8Computer::new();
-        // we should be 2 instructions past.
+        x.registers.poke(0x1, 0x84);
-        // 2 for what we executed
-        assert_eq!(x.registers.peek_pc(), 0x204);
-
         Chip8CpuInstructions::SeVxByte(1, 0x84).execute(&mut x);
-        assert_eq!(x.registers.peek_pc(), 0x208);
+        assert_eq!(x.registers.peek_pc(), 0x204);
     }
 
     #[test]
     fn se_vx_vy_test() {
         // 0x4xkk Skip next instruction if Vx != kk
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x01, 0x84).execute(&mut x);
+        x.registers.poke(0x01, 0x84);
-        Chip8CpuInstructions::LdVxByte(0x02, 0x84).execute(&mut x);
+        x.registers.poke(0x2, 0x84);
-        assert_eq!(x.registers.peek_pc(), 0x204);
-
         // skip, compare 0x84 to 0x84
         Chip8CpuInstructions::SeVxVy(0x1, 0x2).execute(&mut x);
-        assert_eq!(x.registers.peek_pc(), 0x208);
+        assert_eq!(x.registers.peek_pc(), 0x204);
 
-        // load 0x48 (not matching) into V2
+        let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x2, 0x48).execute(&mut x);
+        x.registers.poke(0x01, 0x84);
-        // verify its there.
+        x.registers.poke(0x2, 0x48);
-        assert_eq!(x.registers.peek(2), 0x48);
-        // no skip, compare 0x84 and 0x48
         Chip8CpuInstructions::SeVxVy(0x01, 0x02).execute(&mut x);
-        assert_eq!(x.registers.peek(2), 0x48);
+        assert_eq!(x.registers.peek_pc(), 0x202);
-        assert_eq!(x.registers.peek_pc(), 0x20C);
     }
 
     #[test]
     fn ld_vx_vy_test() {
         // 0x8xy0 Set value of Vy in Vx
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x01, 0x01).execute(&mut x);
+        x.registers.poke(0x01, 0x01);
-        Chip8CpuInstructions::LdVxByte(0x02, 0x02).execute(&mut x);
+        x.registers.poke(0x02, 0x02);
-        assert_eq!(x.registers.peek_pc(), 0x204);
-        assert_eq!(x.registers.peek(1), 0x01);
         Chip8CpuInstructions::LdVxVy(0x01, 0x02).execute(&mut x);
         assert_eq!(x.registers.peek(1), 0x02);
-        assert_eq!(x.registers.peek_pc(), 0x206);
     }
 
     #[test]
@@ -1005,11 +1000,10 @@ mod test {
         // | 0b0000 1010 (0x0A)
         //   0b0101 1010 (0x5A)
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(1, 0x50).execute(&mut x);
+        x.registers.poke(0x01, 0b01010000);
-        Chip8CpuInstructions::LdVxByte(2, 0x0A).execute(&mut x);
+        x.registers.poke(0x02, 0b00001010);
         Chip8CpuInstructions::OrVxVy(1, 2).execute(&mut x);
-        assert_eq!(x.registers.peek(1), 0x5A);
+        assert_eq!(x.registers.peek(1), 0b01011010);
-        assert_eq!(x.registers.peek_pc(), 0x206);
     }
 
     #[test]
@@ -1019,11 +1013,10 @@ mod test {
         // & 0b1100 1010 (0xCA)
         //   0b1100 1000 (0xC8)
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(1, 0xFC).execute(&mut x);
+        x.registers.poke(0x01, 0xFC);
-        Chip8CpuInstructions::LdVxByte(2, 0xCA).execute(&mut x);
+        x.registers.poke(0x02, 0xCA);
         Chip8CpuInstructions::AndVxVy(1, 2).execute(&mut x);
         assert_eq!(x.registers.peek(1), 0xC8);
-        assert_eq!(x.registers.peek_pc(), 0x206);
     }
 
     #[test]
@@ -1033,11 +1026,10 @@ mod test {
         // ^ 0b1100 1010 (0xCA)
         //   0b0011 0110 (0x36)
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(1, 0xFC).execute(&mut x);
+        x.registers.poke(0x01, 0b11111100);
-        Chip8CpuInstructions::LdVxByte(2, 0xCA).execute(&mut x);
+        x.registers.poke(0x02, 0b11001010);
         Chip8CpuInstructions::XorVxVy(1, 2).execute(&mut x);
-        assert_eq!(x.registers.peek(1), 0x36);
+        assert_eq!(x.registers.peek(1), 0b00110110);
-        assert_eq!(x.registers.peek_pc(), 0x206);
     }
 
     #[test]
@@ -1048,24 +1040,20 @@ mod test {
         // + 0x01           0x01
         //   0x02 F0        0x00 F1
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0xf, 0x00).execute(&mut x);
+        x.registers.poke(0x0f, 00);
-        Chip8CpuInstructions::LdVxByte(1, 0x01).execute(&mut x);
+        x.registers.poke(0x01, 0x01);
-        Chip8CpuInstructions::LdVxByte(2, 0x01).execute(&mut x);
+        x.registers.poke(0x02, 0x01);
-        Chip8CpuInstructions::AddVxVy(1, 2).execute(&mut x);
+        Chip8CpuInstructions::AddVxVy(0x01, 0x02).execute(&mut x);
-        // T1
+        assert_eq!(x.registers.peek(0xf), 0x00);
-        assert_eq!(x.registers.peek(0xf), 0);
+        assert_eq!(x.registers.peek(0x01), 0x02);
-        assert_eq!(x.registers.peek(1), 2);
-        assert_eq!(x.registers.peek_pc(), 0x208);
 
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0xf, 0x00).execute(&mut x);
+        x.registers.poke(0x0f, 0x00);
-        Chip8CpuInstructions::LdVxByte(0x1, 0xff).execute(&mut x);
+        x.registers.poke(0x01, 0xff);
-        Chip8CpuInstructions::LdVxByte(0x2, 0x01).execute(&mut x);
+        x.registers.poke(0x02, 0x01);
         Chip8CpuInstructions::AddVxVy(1, 2).execute(&mut x);
-        // T2
         assert_eq!(x.registers.peek(0xf), 1);
         assert_eq!(x.registers.peek(1), 0);
-        assert_eq!(x.registers.peek_pc(), 0x208)
     }
 
     #[test]
@@ -1076,21 +1064,19 @@ mod test {
         If the least-significant bit of Vx is 1, then VF is set to 1, otherwise 0. Then Vx is divided by 2.
         */
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0xf, 0x00).execute(&mut x);
+        x.registers.poke(0x0f, 0x00);
-        Chip8CpuInstructions::LdVxByte(0x1, 0x08).execute(&mut x);   // 0b0000 1000 (0x08)
+        x.registers.poke(0x01, 0b00001000);
-        Chip8CpuInstructions::LdVxByte(0x2, 0x2).execute(&mut x);
+        x.registers.poke(0x02, 0b00000000);
         Chip8CpuInstructions::ShrVxVy(0x1, 0x2).execute(&mut x);     // 0b0000 0010 (0x02) (Not Set)
-        assert_eq!(x.registers.peek(1), 0x04);
+        assert_eq!(x.registers.peek(1), 0b00000100);
         assert_eq!(x.registers.peek(0xf), 0);
-        assert_eq!(x.registers.peek_pc(), 0x208);
 
         x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0xf, 0x00).execute(&mut x);
+        x.registers.poke(0x0f, 0x00);
-        Chip8CpuInstructions::LdVxByte(0x1, 0b00001001).execute(&mut x);   // 0b0000 1001 (0x09)
+        x.registers.poke(0x01, 0b00001001);
-        Chip8CpuInstructions::ShrVxVy(0x1, 0x2).execute(&mut x);     // 0b0000 0010 (0x02) (Set)
+        Chip8CpuInstructions::ShrVxVy(0x1, 0x2).execute(&mut x);
-        assert_eq!(x.registers.peek(1), 0x04);
+        assert_eq!(x.registers.peek(1), 0b00000100);
         assert_eq!(x.registers.peek(0xf), 1);
-        assert_eq!(x.registers.peek_pc(), 0x206);
     }
 
     #[test]
@@ -1105,7 +1091,7 @@ mod test {
     fn jp_v0addr_test() {
         let mut x = Chip8Computer::new();
         /// jump to I + nnn
-        Chip8CpuInstructions::LdVxByte(0x0, 0xFF).execute(&mut x);
+        x.registers.poke(0x0, 0xff);
         Chip8CpuInstructions::JpV0Addr(0x100).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0x1FF);
     }
@@ -1120,22 +1106,21 @@ mod test {
     #[test]
     fn skip_next_instruction_ne_text() {
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0xf0).execute(&mut x);
+        x.registers.poke(0x1, 0xf0);
-        // 202
         Chip8CpuInstructions::SneVxByte(0x1, 0x0f).execute(&mut x);
-        // 204+2
+        assert_eq!(x.registers.peek_pc(), 0x204);
-        assert_eq!(x.registers.peek_pc(), 0x206);
-        Chip8CpuInstructions::SneVxByte(0x1, 0xf0).execute(&mut x);
-        // 208
-        assert_eq!(x.registers.peek_pc(), 0x208);
-    }
 
+        let mut x = Chip8Computer::new();
+        x.registers.poke(0x1, 0xf0);
+        Chip8CpuInstructions::SneVxByte(0x1, 0xf0).execute(&mut x);
+        assert_eq!(x.registers.peek_pc(), 0x202);
+    }
 
     #[test]
     fn addivx_test() {
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdIAddr(0xabc).execute(&mut x);
+        x.registers.poke_i(0xabc);
-        Chip8CpuInstructions::LdVxByte(0x0, 0x10).execute(&mut x);
+        x.registers.poke(0x0, 0x10);
         Chip8CpuInstructions::AddIVx(0x0).execute(&mut x);
         assert_eq!(x.registers.peek_i(), 0xacc);
     }
@@ -1143,7 +1128,7 @@ mod test {
     #[test]
     fn ldstvt_test() {
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x01, 0xf0).execute(&mut x);
+        x.registers.poke(0x1, 0xf0);
         Chip8CpuInstructions::LdStVx(0x01).execute(&mut x);
         assert_eq!(x.sound_timer.current(), 0xf0);
         x.sound_timer.tick();
@@ -1159,26 +1144,12 @@ mod test {
         let new_value = x.registers.peek(0x1);
         assert!(new_value < 0x10);
     }
-    /*
-        #[test]
-        fn skp_vx_test() {
-            let mut x  = Chip8Computer::new();
-            x.keypad.push_key(0x1);
-            Chip8CpuInstructions::LdVxByte(0x1, 0x1).execute(&mut x);
-            Chip8CpuInstructions::SkpVx(0x1).execute(&mut x);
-            assert_eq!(x.registers.peek_pc(), 0x208);
-            x.keypad.release_key(0x1);
-            Chip8CpuInstructions::SkpVx(0x1).execute(&mut x);
-            assert_eq!(x.registers.peek_pc(), 0x20A);
-        }
-
-     */
 
     #[test]
     fn add_vx_byte_test() {
         let mut x = Chip8Computer::new();
         // set a value in the register
-        Chip8CpuInstructions::LdVxByte(0x1, 0xab).execute(&mut x);
+        x.registers.poke(0x01, 0xab);
         // add 0x10 to register
         Chip8CpuInstructions::AddVxByte(0x1, 0x10).execute(&mut x);
         assert_eq!(x.registers.peek(1), 0xbb);
@@ -1188,30 +1159,33 @@ mod test {
     fn sub_vx_vy_test() {
         let mut x = Chip8Computer::new();
         // load values in 2 registers
-        Chip8CpuInstructions::LdVxByte(0x01, 0x10).execute(&mut x);
+        x.registers.poke(0x1, 0x10);
-        Chip8CpuInstructions::LdVxByte(0x02, 0x08).execute(&mut x);
+        x.registers.poke(0x2, 0x08);
         Chip8CpuInstructions::SubVxVy(0x1, 0x02).execute(&mut x);
         assert_eq!(x.registers.peek(0xf), 0);
         assert_eq!(x.registers.peek(0x1), 0x8);
-        assert_eq!(x.registers.peek_pc(), 0x206);
+        assert_eq!(x.registers.peek_pc(), 0x202);
     }
 
     #[test]
     fn sne_vx_vy_test() {
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0x10).execute(&mut x);
+        x.registers.poke(0x1, 0x10);
-        Chip8CpuInstructions::LdVxByte(0x2, 0x10).execute(&mut x);
+        x.registers.poke(0x2, 0x10);
         Chip8CpuInstructions::SneVxVy(0x1, 0x2).execute(&mut x);
-        assert_eq!(x.registers.peek_pc(), 0x206);
+        assert_eq!(x.registers.peek_pc(), 0x202);
-        Chip8CpuInstructions::LdVxByte(0x2, 0x00).execute(&mut x);
+
+        let mut x = Chip8Computer::new();
+        x.registers.poke(0x1, 0x10);
+        x.registers.poke(0x2, 0x00);
         Chip8CpuInstructions::SneVxVy(0x01, 0x02).execute(&mut x);
-        assert_eq!(x.registers.peek_pc(), 0x20C)
+        assert_eq!(x.registers.peek_pc(), 0x204)
     }
 
     #[test]
     fn ld_dt_vx_test() {
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0x10).execute(&mut x);
+        x.registers.poke(0x1, 0x10);
         Chip8CpuInstructions::LdDtVx(0x1).execute(&mut x);
         assert_eq!(x.delay_timer.current(), 0x10);
         for i in 0..0x20 {
@@ -1223,13 +1197,12 @@ mod test {
     #[test]
     fn ld_vx_dt_test() {
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0xf0).execute(&mut x);
+        x.registers.poke(0x1, 0xf0);
         Chip8CpuInstructions::LdDtVx(0x1).execute(&mut x);
         x.delay_timer.tick();
         x.delay_timer.tick();
         x.delay_timer.tick();
-        Chip8CpuInstructions::LdVxDt(0x1).execute(&mut x);
+        assert_eq!(x.delay_timer.current(), 0xed);
-        assert_eq!(x.registers.peek(0x1), 0xed);
     }
 
     #[test]
@@ -1241,20 +1214,18 @@ mod test {
         // The carry flag (VF) is set to 1 if there is no borrow (i.e., Vy is greater
         // than or equal to Vx), and it is set to 0 if there is a borrow.
 
-
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0xa0).execute(&mut x);
+        x.registers.poke(0x1, 0xa0);
-        Chip8CpuInstructions::LdVxByte(0x2, 0xab).execute(&mut x);
+        x.registers.poke(0x2, 0xab);
         Chip8CpuInstructions::SubnVxVy(0x1, 0x2).execute(&mut x);
-
         // expect the result to be 0x0b
         assert_eq!(x.registers.peek(0x1), 0x0b);
         // expect the vf register to be set to 1 as there was overflow
         assert_eq!(x.registers.peek(0xf), 0x0);
 
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0xab).execute(&mut x);
+        x.registers.poke(0x01, 0xab);
-        Chip8CpuInstructions::LdVxByte(0x2, 0xa0).execute(&mut x);
+        x.registers.poke(0x02, 0xa0);
         Chip8CpuInstructions::SubnVxVy(0x1, 0x2).execute(&mut x);
 
         // expect the result to be 11110101, -0xB, -11, 245, 0xF5
@@ -1263,21 +1234,20 @@ mod test {
     }
 
     #[test]
-    fn shl_vx_vy_test() {
+    fn shl_vx_vy_test_1() {
         // 8xyE - SHL Vx {, Vy}
         // Set Vx = Vx SHL 1.
         //
         // If the most-significant bit of Vx is 1, then VF is set to 1, otherwise to 0. Then Vx is multiplied by 2.
 
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0b00100000).execute(&mut x);
+        x.registers.poke(0x1, 0b00100000);
         Chip8CpuInstructions::ShlVxVy(0x1, 0x1).execute(&mut x);
         assert_eq!(x.registers.peek(0x1), 0b01000000);
         assert_eq!(x.registers.peek(0xf), 0x0);
 
-
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0b10101010).execute(&mut x);
+        x.registers.poke(0x1,  0b10101010);
         Chip8CpuInstructions::ShlVxVy(0x1, 0x1).execute(&mut x);
         assert_eq!(x.registers.peek(0x1), 0b01010100);
         assert_eq!(x.registers.peek(0xf), 0x1);
@@ -1292,12 +1262,13 @@ mod test {
         let mut x = Chip8Computer::new();
         // target_sprite = 2
         // target_offset = 0x5
-        Chip8CpuInstructions::LdVxByte(0x1, 0x2).execute(&mut x);
+        x.registers.poke(0x1, 0x2);
         Chip8CpuInstructions::LdFVx(0x1).execute(&mut x);
 
         assert_eq!(x.registers.peek_i(), 0x5);
 
-        Chip8CpuInstructions::LdVxByte(0x1, 0x6).execute(&mut x);
+        let mut x = Chip8Computer::new();
+        x.registers.poke(0x01, 0x06);
         Chip8CpuInstructions::LdFVx(0x1).execute(&mut x);
         assert_eq!(x.registers.peek_i(), 25);
     }
@@ -1313,10 +1284,8 @@ mod test {
         let mut x = Chip8Computer::new();
 
         // load the value 123 (0x7b)
-        Chip8CpuInstructions::LdVxByte(0x1, 0x7b).execute(&mut x);
+        x.registers.poke(0x1, 0x7b);
-        // set I to 0x500
+        x.registers.poke_i(0x500);
-        Chip8CpuInstructions::LdIAddr(0x500).execute(&mut x);
-        ;
         Chip8CpuInstructions::LdBVx(0x1).execute(&mut x);
         assert_eq!(x.memory.peek(0x500), 0x1);
         assert_eq!(x.memory.peek(0x501), 0x2);
@@ -1366,15 +1335,16 @@ mod test {
         // where to load from
         x.registers.poke_i(0x500);
         // how much to load
-        x.registers.poke(0x0, to_load.len() as u8);
+        x.registers.poke(0x6, to_load.len() as u8);
 
         // then copying them values memory to registers
-        Chip8CpuInstructions::LdVxI(0x0).execute(&mut x);
+        Chip8CpuInstructions::LdVxI(0x6).execute(&mut x);
 
         // now check that we have the right values in our registers
         for (idx, value) in to_load.iter().enumerate() {
             assert_eq!(x.registers.peek(idx as u8), *value);
         }
+
                 }
 
     #[test]
@@ -1390,7 +1360,6 @@ mod test {
         x.registers.poke(0x1, 0x5);
         Chip8CpuInstructions::SnkpVx(0x1).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0x202);
-
         x.keypad.release_key(0x5);
         Chip8CpuInstructions::SnkpVx(0x1).execute(&mut x);
         assert_eq!(x.registers.peek_pc(), 0x206);
@@ -1447,8 +1416,6 @@ mod test {
                 println!("ROWDATA = \t\t[{row_data:08b}]\tBIT IN BYTE = \t[{bit_in_byte}]\tONE_SHIFT_SET = [{one_shift_set}]\tSHIFTED ONE = [{shifted_one:08b}]");
                 println!("DATA_OFFSET FOR SOURCE DATA {}x{} is {} / offset by {}x{} and should be {} working with byte {:08b}",
                          bit_in_byte, row_in_sprite, data_offset, x_offset, y_offset, one_shift_set, row_data);
-                //          assert_eq!(should_be_set, );
-                assert_eq!(one_shift_set, x.video_memory.peek(data_offset as u16));
             }
         }
     }
@@ -1468,14 +1435,19 @@ mod test {
 
     #[test]
     fn ret_test() {
+        // SETUP
         // Return from a subroutine.
         let mut x = Chip8Computer::new();
         x.stack.push(&0x132);
         x.stack.push(&0xabc);
+        // EXECUTE
         Chip8CpuInstructions::RET.execute(&mut x);
+        // VERIFY
         assert_eq!(x.registers.peek_pc(), 0xabc);
         assert_eq!(x.stack.depth(), 1);
+        // EXECUTE
         Chip8CpuInstructions::RET.execute(&mut x);
+        // VERIFY
         assert_eq!(x.registers.peek_pc(), 0x132);
         assert_eq!(x.stack.depth(), 0);
     }
@@ -1483,15 +1455,10 @@ mod test {
 
     #[test]
     fn ldvxk_test() {
+        // SETUP
         let mut x = Chip8Computer::new();
-        Chip8CpuInstructions::LdVxByte(0x1, 0x1).execute(&mut x);
+        x.registers.poke(0x01, 0x01);
         Chip8CpuInstructions::LdVxK(0x1).execute(&mut x);
         assert!(matches!(x.state, WaitingForKey));
     }
-
-    #[test]
-    fn f6_fail_hard_test() {
-        let mut x = Chip8Computer::new();
-        
-    }
 }

emma/src/chip8/registers.rs

@@ -43,6 +43,9 @@ impl Chip8Registers {
     }
 
     pub fn poke(&mut self, register_number: u8, value: u8) {
+        if register_number > 0xf {
+            panic!("INVALID REGISTER");
+        }
         self.registers[(register_number) as usize] = value;
     }
 
@@ -100,4 +103,23 @@ mod test {
         x.set_pc(0x300);
         assert_eq!(x.peek_pc(), 0x300);
     }
+
+    #[test]
+    #[should_panic]
+    fn invalid_register() {
+        let mut x = Chip8Registers::default();
+        x.poke(0x10, 0xff);
+    }
+
+    #[test]
+    fn format_as_string_looks_right() {
+        let mut x = Chip8Registers::default();
+        for i in 0..0x10 {
+            x.registers[i] = i as u8;
+        }
+        x.pc = 0xabc;
+        x.i_register = 0xcab;
+        let result_string = x.format_as_string();
+        assert_eq!(result_string, String::from("Vx: 0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07\n    0x08 0x09 0x0a 0x0b 0x0c 0x0d 0x0e 0x0f\nI: 0x0cab\tPC: 0x0abc"));
+    }
 }

emma/tests/computer_tests.rs

@@ -0,0 +1,11 @@
+use emmaemu::chip8::computer::Chip8Computer;
+
+#[test]
+fn smoke() { assert!(true) }
+
+#[test]
+fn test_rom_1_works() {
+    let mut x = Chip8Computer::new();
+
+
+}