remove chip8 redundant module

1 files changed, 277 insertions, 0 deletions

diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..5ff782d
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,277 @@
+use std::io::Read;
+use std::io::Write;
+
+const WIDTH: u16 = 64;
+const HEIGHT: u16 = 32;
+const PIXELS: usize = (WIDTH * HEIGHT) as usize;
+
+fn unknown_opcode(opcode: u16) {
+    eprintln!("Unknwown opcode {:#06x}", opcode);
+    std::process::exit(1);
+}
+
+struct RandomGenerator {
+    random: u8,
+}
+
+impl RandomGenerator {
+    fn new() -> Self {
+        Self { random: 92 }
+    }
+}
+
+impl Iterator for RandomGenerator {
+    type Item = u8;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.random ^= self.random << 6;
+        self.random ^= self.random >> 4;
+        self.random ^= self.random << 1;
+        Some(self.random)
+    }
+}
+
+pub struct Chip8 {
+    v: [u8; 16],
+    i: u16,
+    pc: u16,
+    stack: [u16; 16],
+    sp: u16,
+    memory: [u8; 4096],
+    screen: [u8; PIXELS],
+    delay_timer: u8,
+    sound_timer: u8,
+    key: [u8; 16],
+    draw: bool,
+    random: RandomGenerator,
+}
+
+impl Chip8 {
+    pub fn new() -> Self {
+        Self {
+            v: [0; 16],
+            i: 0,
+            pc: 0x200,
+            stack: [0; 16],
+            sp: 0,
+            memory: [0; 4096],
+            screen: [0; PIXELS],
+            delay_timer: 0,
+            sound_timer: 0,
+            key: [0; 16],
+            draw: false,
+            random: RandomGenerator::new(),
+        }
+    }
+
+    pub fn load_rom<R: Read>(&mut self, mut reader: R) -> std::io::Result<()> {
+        reader.read(&mut self.memory[0x200..])?;
+        Ok(())
+    }
+
+    pub fn cycle(&mut self) {
+        let pc = self.pc as usize;
+        let opcode = ((self.memory[pc] as u16) << 8) | self.memory[pc + 1] as u16;
+        let x = ((opcode & 0x0F00) >> 8) as usize;
+        let y = ((opcode & 0x00F0) >> 4) as usize;
+        let n = opcode & 0x000F;
+        let nn = (opcode & 0x00FF) as u8;
+        let nnn = opcode & 0x0FFF;
+        self.pc += 2;
+        match opcode & 0xF000 {
+            0x0000 => match opcode & 0x000F {
+                0x0000 => {
+                    eprintln!("CLS");
+                    self.screen = [0; PIXELS];
+                    self.draw = true;
+                }
+                0x000E => {
+                    eprintln!("RET");
+                    self.sp -= 1;
+                    self.pc = self.stack[self.sp as usize];
+                }
+                _ => unknown_opcode(opcode),
+            },
+            0x1000 => {
+                eprintln!("JP {}", nnn);
+                self.pc = nnn;
+            }
+            0x2000 => {
+                eprintln!("CALL {}", nnn);
+                self.stack[self.sp as usize] = self.pc;
+                self.sp += 1;
+                self.pc = nnn;
+            }
+            0x3000 => {
+                eprintln!("SE V{}, {}", x, nn);
+                if self.v[x] == nn {
+                    self.pc += 2;
+                }
+            }
+            0x4000 => {
+                eprintln!("SNE V{}, {}", x, nn);
+                if self.v[x] != nn {
+                    self.pc += 2;
+                }
+            }
+            0x5000 => {
+                eprintln!("SE V{}, V{}", x, y);
+                if self.v[x] == self.v[y] {
+                    self.pc += 2;
+                }
+            }
+            0x6000 => {
+                eprintln!("LD V{}, {}", x, nn);
+                self.v[x] = nn;
+            }
+            0x7000 => {
+                eprintln!("ADD V{}, {}", x, nn);
+                self.v[x] = self.v[x].wrapping_add(nn);
+            }
+            0x8000 => match opcode & 0x000F {
+                0x0000 => {
+                    eprintln!("LD V{}, V{}", x, y);
+                    self.v[x] = self.v[y];
+                }
+                0x0001 => {
+                    eprintln!("OR V{}, V{}", x, y);
+                    self.v[x] |= self.v[y];
+                }
+                0x0002 => {
+                    eprintln!("AND V{}, V{}", x, y);
+                    self.v[x] &= self.v[y];
+                }
+                0x0003 => {
+                    eprintln!("XOR V{}, V{}", x, y);
+                    self.v[x] ^= self.v[y];
+                }
+                0x0004 => {
+                    eprintln!("ADD V{}, V{}", x, y);
+                    let vx = self.v[x] as u16;
+                    let vy = self.v[y] as u16;
+                    let v = vx + vy;
+                    self.v[0xF] = if v > 255 { 1 } else { 0 };
+                    self.v[x] = v as u8;
+                }
+                0x0005 => {
+                    eprintln!("SUB V{}, V{}", x, y);
+                    self.v[0xF] = if self.v[x] > self.v[y] { 1 } else { 0 };
+                    self.v[x] = self.v[x].wrapping_sub(self.v[y]);
+                }
+                0x0006 => {
+                    eprintln!("SHR V{}", x);
+                    self.v[0xF] = if self.v[x] & 1 == 1 { 1 } else { 0 };
+                    self.v[x] /= 2;
+                }
+                0x0007 => {
+                    eprintln!("SUBN V{}, V{}", x, y);
+                    self.v[0xF] = if self.v[y] > self.v[x] { 1 } else { 0 };
+                    self.v[x] = self.v[y].wrapping_sub(self.v[x]);
+                }
+                0x000E => {
+                    eprintln!("SHL V{}", x);
+                    self.v[0xF] = if (self.v[x] >> 7) & 1 == 1 { 1 } else { 0 };
+                    self.v[x] = self.v[x].wrapping_mul(2);
+                }
+                _ => unknown_opcode(opcode),
+            },
+            0x9000 => {
+                eprintln!("SNE V{}, V{}", x, y);
+                if self.v[x] != self.v[y] {
+                    self.pc += 2;
+                }
+            }
+            0xA000 => {
+                eprintln!("LD I, {}", nnn);
+                self.i = nnn;
+            }
+            0xC000 => {
+                eprintln!("RND V{}, {}", x, nn);
+                self.v[x] = self.random.next().unwrap_or(0) & nn;
+            }
+            0xD000 => {
+                eprintln!("DRW V{}, V{}, {}", x, y, n);
+                let vx = self.v[x] as u16;
+                let vy = self.v[y] as u16;
+                self.v[0xF] = 0;
+                for yy in 0..n {
+                    let pixel = self.memory[(self.i + yy) as usize];
+                    for xx in 0..8 {
+                        if (pixel & (0x80 >> xx)) != 0 {
+                            let si = vx + xx + ((vy + yy) * WIDTH);
+                            if self.screen[si as usize] == 1 {
+                                self.v[0xF] = 1;
+                            }
+                            self.screen[si as usize] ^= 1;
+                        }
+                    }
+                }
+                self.draw = true;
+            }
+            0xF000 => match opcode & 0x00FF {
+                0x001E => {
+                    eprintln!("ADD, I, V{}", x);
+                    self.i += self.v[x] as u16;
+                }
+                0x0033 => {
+                    eprintln!("LD, B, V{}", x);
+                    let i = self.i as usize;
+                    self.memory[i] = self.v[x] / 100;
+                    self.memory[i + 1] = (self.v[x] / 10) % 10;
+                    self.memory[i + 2] = (self.v[x] % 100) % 10;
+                }
+                0x0055 => {
+                    eprintln!("LD [I], V{}", x);
+                    let i = self.i as usize;
+                    self.memory[i..=i + x].copy_from_slice(&self.v[..=x]);
+                }
+                0x0065 => {
+                    eprintln!("LD V{}, [I]", x);
+                    let i = self.i as usize;
+                    self.v[..=x].copy_from_slice(&self.memory[i..=i + x]);
+                }
+                _ => unknown_opcode(opcode),
+            },
+            _ => unknown_opcode(opcode),
+        };
+
+        if self.delay_timer > 0 {
+            self.delay_timer -= 1;
+        }
+
+        if self.sound_timer > 0 {
+            if self.sound_timer == 1 {
+                eprintln!("BEEP");
+            }
+            self.sound_timer -= 1;
+        }
+    }
+
+    pub fn display(&mut self) -> std::io::Result<()> {
+        if self.draw {
+            self.draw = false;
+            self.draw()
+        } else {
+            Ok(())
+        }
+    }
+
+    fn draw(&self) -> std::io::Result<()> {
+        let stdout = std::io::stdout();
+        let mut handle = stdout.lock();
+        handle.write_all(b"\x1B[2J\n")?;
+        for y in 0..HEIGHT {
+            for x in 0..WIDTH {
+                let si = x + y * WIDTH;
+                let buf = if self.screen[si as usize] == 0 {
+                    "░".as_bytes()
+                } else {
+                    "█".as_bytes()
+                };
+                handle.write_all(buf)?;
+            }
+            handle.write_all(b"\n")?;
+        }
+        handle.flush()
+    }
+}