diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/apu.rs | 207 | ||||
| -rw-r--r-- | src/bin.rs | 13 | ||||
| -rw-r--r-- | src/memory.rs | 7 | ||||
| -rw-r--r-- | src/mos6502.rs | 17 |
4 files changed, 195 insertions, 49 deletions
@@ -9,6 +9,11 @@ pub trait Speaker { const CPU_SAMPLE_FREQ: u32 = 240; pub const AUDIO_SAMPLE_FREQ: u32 = 44100; +const TRI_SEQ_TABLE: [u8; 32] = [ + 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 +]; + const LEN_TABLE: [u8; 32] = [ 10, 254, 20, 2, 40, 4, 80, 6, 160, 8, 60, 10, 14, 12, 26, 14, 12, 16, 24, 18, 48, 20, 96, 22, 192, 24, 72, 26, 16, 28, 32, 30, @@ -68,47 +73,48 @@ const TND_TABLE: [u16; 203] = [ ]; struct Sampler { - ticks_remain: u32, - ticks_now: u32, - ticks_unit: u32, - ticks_all: u32, - ticks_extra: u32, - ticks_extra_all: u32, + freq2: u32, + q0: u32, + r0: u32, + ddl: (u32, u32), + cnt: u32, + sec_cnt: u32 } impl Sampler { fn new(freq1: u32, freq2: u32) -> Self { - let unit = freq1 / freq2; - let extra = freq1 - unit * freq2; + let q0 = freq1 / freq2; + let r0 = freq1 - q0 * freq2; Sampler { - ticks_remain: freq1 - extra, - ticks_now: 0, - ticks_unit: unit, - ticks_all: freq1 - extra, - ticks_extra: extra, - ticks_extra_all: extra + freq2, + q0, + r0, + ddl: (q0, r0), + cnt: 0, + sec_cnt: 0 } } fn tick(&mut self) -> (bool, bool) { - let unit = self.ticks_unit; - if self.ticks_now == 0 { - self.ticks_now = unit; - self.ticks_remain -= unit; - if self.ticks_remain == 0 { - /* compensate to last exactly 1 sec */ - self.ticks_now += self.ticks_remain; - /* reload for the next second */ - self.ticks_remain = self.ticks_all; - self.ticks_extra = self.ticks_extra_all; - } - if self.ticks_extra > 0 { - self.ticks_extra -= 1; - self.ticks_now += 1; + let (q, r) = self.ddl; + if self.cnt == q { + let nr = r + self.r0; + self.ddl = if nr > self.freq2 { + (self.q0, nr - self.freq2) + } else { + (self.q0 - 1, nr) + }; + self.cnt = 0; + self.sec_cnt += 1; + let sec = self.sec_cnt == self.freq2; + if sec { + self.sec_cnt = 0 } + (true, sec) + } else { + self.cnt += 1; + (false, false) } - self.ticks_now -= 1; - (self.ticks_now == 0, self.ticks_remain == self.ticks_all) } } @@ -169,16 +175,18 @@ impl Pulse { let mut reload = self.swp_rld; if self.swp_lvl == 0 { reload = true; - let p = self.timer_period; - let mut delta = p >> self.swp_count; - if self.swp_neg { - delta = !delta; - if self.comple { delta += 1; } /* two's complement */ - } - p.wrapping_add(delta); - self.muted = self.timer_period < 8 || (self.timer_period >> 11 != 0); - if !self.muted && self.swp_en && self.swp_count != 0 { - self.timer_period = p; + if self.swp_en { + let mut p = self.timer_period; + let mut delta = p >> self.swp_count; + if self.swp_neg { + delta = !delta; + if self.comple { delta += 1; } /* two's complement */ + } + p = p.wrapping_add(delta); + self.muted = p < 8 || (p >> 11 != 0); + if !self.muted && self.swp_count != 0 { + self.timer_period = p; + } } } else { self.swp_lvl -= 1; @@ -274,15 +282,117 @@ impl Pulse { Pulse {env_period: 0, env_lvl: 0, decay_lvl: 0, env_start: false, env_loop: false, env_const: false, env_vol: 0, swp_count: 0, swp_period: 0, swp_lvl: 0, - swp_en: false, swp_neg: false, swp_rld: false, muted: true, + swp_en: false, swp_neg: false, swp_rld: false, muted: false, len_lvl: 0, timer_period: 0, timer_lvl: 0, seq_wave: 0, seq_cnt: 0, enabled: false, comple} } } +pub struct Triangle { + /* linear counter */ + cnt_rld: bool, + cnt_lvl: u8, + cnt_rld_val: u8, + /* length counter */ + len_lvl: u8, + /* timer */ + timer_period: u16, + timer_lvl: u16, + /* sequencer */ + seq_cnt: u8, + enabled: bool, + /* misc */ + ctrl: bool +} + +impl Triangle { + fn tick_counter(&mut self) { + if self.cnt_rld { + self.cnt_lvl = self.cnt_rld_val + } else if self.cnt_lvl > 0 { + self.cnt_lvl -= 1 + } + if !self.ctrl { + self.cnt_rld = false + } + } + + fn tick_length(&mut self) { + if self.len_lvl > 0 && !self.ctrl { + self.len_lvl -= 1 + } + } + + + fn tick_timer(&mut self) { + if self.len_lvl > 0 && self.cnt_lvl > 0 { + if self.timer_lvl == 0 { + self.timer_lvl = self.timer_period; + if self.seq_cnt == 31 { + self.seq_cnt = 0 + } else { + self.seq_cnt += 1 + } + } else { + self.timer_lvl -= 1 + } + } + } + + fn disable(&mut self) { + self.len_lvl = 0; + self.enabled = false; + } + + fn enable(&mut self) { self.enabled = true } + + fn new() -> Self { + Triangle { + cnt_rld: false, cnt_lvl: 0, cnt_rld_val: 0, + len_lvl: 0, timer_period: 0, timer_lvl: 0, + seq_cnt: 0, enabled: false, ctrl: false + } + } + + fn get_len(&self) -> u8 { self.len_lvl } + fn set_cnt_lvl(&mut self, d: u8) { self.cnt_lvl = d } + fn set_ctrl(&mut self, b: bool) { self.ctrl = b } + fn set_cnt_rld_val(&mut self, d: u8) { self.cnt_rld_val = d } + fn set_timer_peroid(&mut self, p: u16) { self.timer_period = p } + fn set_len(&mut self, d: u8) { + if self.enabled { + self.len_lvl = LEN_TABLE[d as usize] + } + } + + pub fn write_reg1(&mut self, data: u8) { + self.set_cnt_rld_val(data & 0x7f); + self.set_ctrl(data >> 7 == 1); + } + + pub fn write_reg3(&mut self, data: u8) { + self.timer_period = (self.timer_period & 0xff00) | data as u16 + } + + pub fn write_reg4(&mut self, data: u8) { + self.set_len(data >> 3); + self.timer_period = (self.timer_period & 0x00ff) | ((data as u16 & 7) << 8); + self.seq_cnt = 0; + self.timer_lvl = self.timer_period; + self.cnt_rld = true; + } + + fn output(&self) -> u8 { + let len = self.len_lvl > 0; + let lin = self.cnt_lvl > 0; + if len && lin { TRI_SEQ_TABLE[self.seq_cnt as usize] } else { 0 } + } +} + pub struct APU<'a> { pub pulse1: Pulse, pub pulse2: Pulse, + pub triangle: Triangle, frame_lvl: u8, frame_mode: bool, /* true for 5-step mode */ frame_inh: bool, @@ -297,6 +407,7 @@ impl<'a> APU<'a> { fn tick_env(&mut self) { self.pulse1.tick_env(); self.pulse2.tick_env(); + self.triangle.tick_counter(); } fn tick_len_swp(&mut self) { @@ -304,11 +415,13 @@ impl<'a> APU<'a> { self.pulse1.tick_sweep(); self.pulse2.tick_length(); self.pulse2.tick_sweep(); + self.triangle.tick_length(); } pub fn new(spkr: &'a mut Speaker) -> Self { APU { pulse1: Pulse::new(false), pulse2: Pulse::new(true), + triangle: Triangle::new(), frame_lvl: 0, frame_mode: false, frame_int: false, frame_inh: false, cpu_sampler: Sampler::new(mos6502::CPU_FREQ, CPU_SAMPLE_FREQ), audio_sampler: Sampler::new(mos6502::CPU_FREQ, AUDIO_SAMPLE_FREQ), @@ -320,13 +433,14 @@ impl<'a> APU<'a> { pub fn output(&self) -> u16 { let pulse_out = PULSE_TABLE[(self.pulse1.output() + self.pulse2.output()) as usize]; - let tnd_out = TND_TABLE[0]; + let tnd_out = TND_TABLE[(self.triangle.output() * 3) as usize]; pulse_out + tnd_out } pub fn read_status(&mut self) -> u8 { let res = if self.pulse1.get_len() > 0 { 1 } else { 0 } | - (if self.pulse1.get_len() > 0 { 1 } else { 0 }) << 1 | + (if self.pulse2.get_len() > 0 { 1 } else { 0 }) << 1 | + (if self.triangle.get_len() > 0 { 1 } else { 0 }) << 2 | (if self.frame_int { 1 } else { 0 }) << 6; if self.frame_lvl != 3 { self.frame_int = false; /* clear interrupt flag */ @@ -343,6 +457,10 @@ impl<'a> APU<'a> { 0 => self.pulse2.disable(), _ => self.pulse2.enable() } + match data & 0x4 { + 0 => self.triangle.disable(), + _ => self.triangle.enable() + } } pub fn write_frame_counter(&mut self, data: u8) { @@ -350,11 +468,12 @@ impl<'a> APU<'a> { self.frame_mode = data >> 7 == 1; } - pub fn tick_timer(&mut self) { + fn tick_timer(&mut self) { if self.cycle_even { self.pulse1.tick_timer(); self.pulse2.tick_timer(); } + self.triangle.tick_timer(); } fn tick_frame_counter(&mut self) -> bool { @@ -370,8 +370,19 @@ fn main() { 1 => Box::new(mapper::Mapper1::new(cart)), _ => panic!("unsupported mapper {}", mapper_id) }; + let dur_sec = Duration::from_millis(1000); + let mut tim_sec = Instant::now(); + let mut f = || { + let e = tim_sec.elapsed(); + if e < dur_sec { + let diff = dur_sec - e; + sleep(diff); + } + tim_sec = Instant::now(); + }; + let mapper = RefCell::new(&mut (*m) as &mut mapper::Mapper); - let mut cpu = CPU::new(CPUMemory::new(&mapper, Some(&p1ctl), None)); + let mut cpu = CPU::new(CPUMemory::new(&mapper, Some(&p1ctl), None), &mut f); let mut ppu = PPU::new(PPUMemory::new(&mapper), &mut win); let mut apu = APU::new(&mut spkr); let cpu_ptr = &mut cpu as *mut CPU; diff --git a/src/memory.rs b/src/memory.rs index bea84fc..e57bdf4 100644 --- a/src/memory.rs +++ b/src/memory.rs @@ -67,7 +67,7 @@ impl<'a> CPUMemory<'a> { if apu.tick() { cpu.trigger_irq() } - cpu.cycle -= 1; + cpu.tick(); } } @@ -86,7 +86,9 @@ impl<'a> VMem for CPUMemory<'a> { _ => 0 } } else if addr < 0x4020 { + let apu = self.bus.get_apu(); match addr { + 0x4015 => apu.read_status(), 0x4016 => if let Some(c) = self.ctl1 { c.read() } else { 0 }, 0x4017 => if let Some(c) = self.ctl2 { c.read() } else { 0 }, _ => 0 @@ -133,6 +135,9 @@ impl<'a> VMem for CPUMemory<'a> { 0x4005 => apu.pulse2.write_reg2(data), 0x4006 => apu.pulse2.write_reg3(data), 0x4007 => apu.pulse2.write_reg4(data), + 0x4008 => apu.triangle.write_reg1(data), + 0x400a => apu.triangle.write_reg3(data), + 0x400b => apu.triangle.write_reg4(data), 0x4015 => apu.write_status(data), 0x4017 => apu.write_frame_counter(data), 0x4014 => ppu.write_oamdma(data, cpu), diff --git a/src/mos6502.rs b/src/mos6502.rs index 6c5a140..a9fac8c 100644 --- a/src/mos6502.rs +++ b/src/mos6502.rs @@ -602,8 +602,10 @@ pub struct CPU<'a> { ea: u16, /* effective address */ imm_val: u8, pub cycle: u32, + pub elapsed: u32, int: Option<IntType>, - pub mem: CPUMemory<'a> + pub mem: CPUMemory<'a>, + sec_callback: &'a mut FnMut(), } macro_rules! make_int { @@ -637,7 +639,7 @@ impl<'a> CPU<'a> { #[inline(always)] pub fn get_over(&self) -> u8 { (self.status >> 6) & 1 } #[inline(always)] pub fn get_neg(&self) -> u8 { (self.status >> 7) & 1 } - pub fn new(mem: CPUMemory<'a>) -> Self { + pub fn new(mem: CPUMemory<'a>, sec_callback: &'a mut FnMut()) -> Self { let pc = 0; /* nes power up state */ let a = 0; @@ -652,7 +654,7 @@ impl<'a> CPU<'a> { opr: 0, ea: 0, imm_val: 0, int: None, acc: false, - mem} + mem, elapsed: 0, sec_callback} } pub fn start(&mut self) { @@ -689,6 +691,15 @@ impl<'a> CPU<'a> { //(self.cycle - cycle0) as u8 } + pub fn tick(&mut self) { + self.cycle -= 1; + self.elapsed += 1; + if self.elapsed == CPU_FREQ { + self.elapsed = 0; + (self.sec_callback)(); + } + } + pub fn reset(&mut self) { self.pc = read16!(self.mem, RESET_VECTOR as u16); self.sp = self.sp.wrapping_sub(3); |