mirror of
https://github.com/transistorfet/moa.git
synced 2024-06-09 16:29:29 +00:00
600 lines
19 KiB
Rust
600 lines
19 KiB
Rust
|
|
use std::num::NonZeroU8;
|
|
use std::collections::VecDeque;
|
|
|
|
use moa_core::{debug, warn};
|
|
use moa_core::{System, Error, Clock, ClockElapsed, Address, Addressable, Steppable, Transmutable};
|
|
use moa_core::host::{Host, Audio};
|
|
use moa_core::host::audio::{SineWave, db_to_gain};
|
|
|
|
const DEV_NAME: &str = "ym2612";
|
|
|
|
const CHANNELS: usize = 8;
|
|
|
|
#[derive(Copy, Clone, Debug)]
|
|
enum EnvelopeState {
|
|
Attack,
|
|
Decay1,
|
|
Decay2,
|
|
Release,
|
|
}
|
|
|
|
#[derive(Copy, Clone, Debug)]
|
|
enum OperatorAlgorithm {
|
|
A0,
|
|
A1,
|
|
A2,
|
|
A3,
|
|
A4,
|
|
A5,
|
|
A6,
|
|
A7,
|
|
}
|
|
|
|
|
|
#[derive(Clone)]
|
|
struct Operator {
|
|
wave: SineWave,
|
|
frequency: f32,
|
|
multiplier: f32,
|
|
total_level: f32,
|
|
|
|
attack_rate: usize,
|
|
first_decay_rate: usize,
|
|
first_decay_level: usize,
|
|
second_decay_rate: usize,
|
|
release_rate: usize,
|
|
|
|
envelope_state: EnvelopeState,
|
|
last_event: Clock,
|
|
envelope_gain: f32,
|
|
}
|
|
|
|
impl Operator {
|
|
fn new(sample_rate: usize) -> Self {
|
|
Self {
|
|
wave: SineWave::new(400.0, sample_rate),
|
|
frequency: 400.0,
|
|
multiplier: 1.0,
|
|
total_level: 0.0,
|
|
|
|
attack_rate: 0,
|
|
first_decay_rate: 0,
|
|
first_decay_level: 0,
|
|
second_decay_rate: 0,
|
|
release_rate: 0,
|
|
|
|
envelope_state: EnvelopeState::Attack,
|
|
last_event: 0,
|
|
envelope_gain: 0.0,
|
|
}
|
|
}
|
|
|
|
fn set_frequency(&mut self, frequency: f32) {
|
|
self.frequency = frequency;
|
|
}
|
|
|
|
fn set_total_level(&mut self, db: f32) {
|
|
self.total_level = db_to_gain(db);
|
|
}
|
|
|
|
fn set_attack_rate(&mut self, rate: usize) {
|
|
self.attack_rate = rate;
|
|
}
|
|
|
|
fn set_first_decay_rate(&mut self, rate: usize) {
|
|
self.first_decay_rate = rate;
|
|
}
|
|
|
|
fn set_first_decay_level(&mut self, rate: usize) {
|
|
self.first_decay_level = rate;
|
|
}
|
|
|
|
fn set_second_decay_rate(&mut self, rate: usize) {
|
|
self.second_decay_rate = rate;
|
|
}
|
|
|
|
fn set_release_rate(&mut self, rate: usize) {
|
|
self.release_rate = rate;
|
|
}
|
|
|
|
fn notify_state_change(&mut self, state: bool, event_clock: Clock) {
|
|
self.last_event = event_clock;
|
|
if state {
|
|
self.envelope_state = EnvelopeState::Attack;
|
|
self.envelope_gain = 0.0;
|
|
} else {
|
|
self.envelope_state = EnvelopeState::Release;
|
|
}
|
|
}
|
|
|
|
fn reset(&mut self) {
|
|
self.wave.reset();
|
|
}
|
|
|
|
fn set_multiplier(&mut self, _frequency: f32, multiplier: f32) {
|
|
self.multiplier = multiplier;
|
|
}
|
|
|
|
fn get_sample(&mut self, modulator: f32, event_clock: Clock) -> f32 {
|
|
self.wave.set_frequency((self.frequency * self.multiplier) + modulator);
|
|
let sample = self.wave.next().unwrap();
|
|
|
|
/*
|
|
let time_since_last = event_clock - self.last_event;
|
|
match self.envelope_state {
|
|
EnvelopeState::Attack => {
|
|
let gain = rate_to_gain(self.attack_rate, time_since_last).min(self.total_level);
|
|
if gain == self.total_level {
|
|
self.envelope_state = EnvelopeState::Decay1;
|
|
}
|
|
sample / gain
|
|
},
|
|
EnvelopeState::Decay1 => {
|
|
let gain = (self.total_level - rate_to_gain(self.first_decay_rate, time_since_last)).max(self.total_level / 2.0);
|
|
if gain == self.total_level / 2.0 {
|
|
self.envelope_state = EnvelopeState::Decay2;
|
|
}
|
|
sample / gain
|
|
},
|
|
EnvelopeState::Decay2 => {
|
|
let gain = (self.total_level / 2.0 - rate_to_gain(self.second_decay_rate, time_since_last)).max(0.0);
|
|
sample / gain
|
|
},
|
|
EnvelopeState::Release => {
|
|
let gain = (self.total_level / 2.0 - rate_to_gain(self.release_rate, time_since_last)).max(0.0);
|
|
sample / gain
|
|
},
|
|
}
|
|
*/
|
|
sample
|
|
}
|
|
}
|
|
|
|
fn rate_to_gain(rate: usize, event_clock: Clock) -> f32 {
|
|
event_clock as f32 * rate as f32
|
|
}
|
|
|
|
#[derive(Clone)]
|
|
struct Channel {
|
|
operators: Vec<Operator>,
|
|
on_state: u8,
|
|
next_on_state: u8,
|
|
base_frequency: f32,
|
|
algorithm: OperatorAlgorithm,
|
|
}
|
|
|
|
impl Channel {
|
|
fn new(sample_rate: usize) -> Self {
|
|
Self {
|
|
operators: vec![Operator::new(sample_rate); 4],
|
|
on_state: 0,
|
|
next_on_state: 0,
|
|
base_frequency: 0.0,
|
|
algorithm: OperatorAlgorithm::A0,
|
|
}
|
|
}
|
|
|
|
fn set_frequency(&mut self, frequency: f32) {
|
|
self.base_frequency = frequency;
|
|
for operator in self.operators.iter_mut() {
|
|
operator.set_frequency(frequency);
|
|
}
|
|
}
|
|
|
|
fn reset(&mut self) {
|
|
for operator in self.operators.iter_mut() {
|
|
operator.reset();
|
|
}
|
|
}
|
|
|
|
fn get_sample(&mut self, event_clock: Clock) -> f32 {
|
|
if self.on_state != self.next_on_state {
|
|
self.on_state = self.next_on_state;
|
|
for (i, operator) in self.operators.iter_mut().enumerate() {
|
|
operator.notify_state_change(((self.on_state >> i) & 0x01) != 0, event_clock);
|
|
}
|
|
}
|
|
|
|
if self.on_state != 0 {
|
|
self.get_algorithm_sample(event_clock)
|
|
} else {
|
|
0.0
|
|
}
|
|
}
|
|
|
|
fn get_algorithm_sample(&mut self, event_clock: Clock) -> f32 {
|
|
match self.algorithm {
|
|
OperatorAlgorithm::A0 => {
|
|
let modulator0 = self.operators[0].get_sample(0.0, event_clock);
|
|
let modulator1 = self.operators[1].get_sample(modulator0, event_clock);
|
|
let modulator2 = self.operators[2].get_sample(modulator1, event_clock);
|
|
self.operators[3].get_sample(modulator2, event_clock)
|
|
},
|
|
OperatorAlgorithm::A1 => {
|
|
let sample1 = self.operators[0].get_sample(0.0, event_clock) + self.operators[1].get_sample(0.0, event_clock);
|
|
let sample2 = self.operators[2].get_sample(sample1, event_clock);
|
|
self.operators[3].get_sample(sample2, event_clock)
|
|
},
|
|
OperatorAlgorithm::A2 => {
|
|
let sample1 = self.operators[1].get_sample(0.0, event_clock);
|
|
let sample2 = self.operators[2].get_sample(sample1, event_clock);
|
|
let sample3 = self.operators[0].get_sample(0.0, event_clock) + sample2;
|
|
self.operators[3].get_sample(sample3, event_clock)
|
|
},
|
|
OperatorAlgorithm::A3 => {
|
|
let sample1 = self.operators[0].get_sample(0.0, event_clock);
|
|
let sample2 = self.operators[1].get_sample(sample1, event_clock);
|
|
let sample3 = self.operators[2].get_sample(0.0, event_clock);
|
|
self.operators[3].get_sample(sample2 + sample3, event_clock)
|
|
},
|
|
OperatorAlgorithm::A4 => {
|
|
let sample1 = self.operators[0].get_sample(0.0, event_clock);
|
|
let sample2 = self.operators[1].get_sample(sample1, event_clock);
|
|
let sample3 = self.operators[2].get_sample(0.0, event_clock);
|
|
let sample4 = self.operators[3].get_sample(sample3, event_clock);
|
|
sample2 + sample4
|
|
},
|
|
OperatorAlgorithm::A5 => {
|
|
let sample1 = self.operators[0].get_sample(0.0, event_clock);
|
|
self.operators[1].get_sample(sample1, event_clock) + self.operators[2].get_sample(sample1, event_clock) + self.operators[3].get_sample(sample1, event_clock)
|
|
},
|
|
OperatorAlgorithm::A6 => {
|
|
let sample1 = self.operators[0].get_sample(0.0, event_clock);
|
|
let sample2 = self.operators[1].get_sample(sample1, event_clock);
|
|
sample2 + self.operators[2].get_sample(0.0, event_clock) + self.operators[3].get_sample(0.0, event_clock)
|
|
},
|
|
OperatorAlgorithm::A7 => {
|
|
self.operators[0].get_sample(0.0, event_clock)
|
|
+ self.operators[1].get_sample(0.0, event_clock)
|
|
+ self.operators[2].get_sample(0.0, event_clock)
|
|
+ self.operators[3].get_sample(0.0, event_clock)
|
|
},
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
struct Dac {
|
|
enabled: bool,
|
|
samples: VecDeque<f32>,
|
|
}
|
|
|
|
impl Default for Dac {
|
|
fn default() -> Self {
|
|
Self {
|
|
enabled: false,
|
|
samples: VecDeque::with_capacity(100),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Dac {
|
|
fn add_sample(&mut self, sample: f32) {
|
|
self.samples.push_back(sample);
|
|
}
|
|
|
|
fn get_sample(&mut self) -> f32 {
|
|
if let Some(data) = self.samples.pop_front() {
|
|
data
|
|
} else {
|
|
0.0
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
pub struct Ym2612 {
|
|
source: Box<dyn Audio>,
|
|
selected_reg_0: Option<NonZeroU8>,
|
|
selected_reg_1: Option<NonZeroU8>,
|
|
|
|
clock_frequency: u32,
|
|
event_clock_period: ClockElapsed,
|
|
channels: Vec<Channel>,
|
|
channel_frequencies: [(u8, u16); CHANNELS],
|
|
dac: Dac,
|
|
|
|
timer_a_enable: bool,
|
|
timer_a: u16,
|
|
timer_a_current: u16,
|
|
timer_a_overflow: bool,
|
|
|
|
timer_b_enable: bool,
|
|
timer_b: u8,
|
|
timer_b_current: u8,
|
|
timer_b_overflow: bool,
|
|
|
|
registers: Vec<u8>,
|
|
}
|
|
|
|
impl Ym2612 {
|
|
pub fn create<H: Host>(host: &mut H, clock_frequency: u32) -> Result<Self, Error> {
|
|
let source = host.create_audio_source()?;
|
|
let sample_rate = source.samples_per_second();
|
|
Ok(Self {
|
|
source,
|
|
selected_reg_0: None,
|
|
selected_reg_1: None,
|
|
|
|
clock_frequency,
|
|
event_clock_period: 3 * 144 * 1_000_000_000 / clock_frequency as ClockElapsed,
|
|
channels: vec![Channel::new(sample_rate); 8],
|
|
channel_frequencies: [(0, 0); CHANNELS],
|
|
|
|
dac: Dac::default(),
|
|
|
|
timer_a_enable: false,
|
|
timer_a: 0,
|
|
timer_a_current: 0,
|
|
timer_a_overflow: false,
|
|
|
|
timer_b_enable: false,
|
|
timer_b: 0,
|
|
timer_b_current: 0,
|
|
timer_b_overflow: false,
|
|
|
|
registers: vec![0; 512],
|
|
})
|
|
}
|
|
|
|
pub fn set_register(&mut self, bank: u8, reg: u8, data: u8) {
|
|
// Keep a copy for debugging purposes, and if the original values are needed
|
|
self.registers[bank as usize * 256 + reg as usize] = data;
|
|
|
|
//warn!("{}: set reg {}{:x} to {:x}", DEV_NAME, bank, reg, data);
|
|
match reg {
|
|
0x24 => {
|
|
self.timer_a = (self.timer_a & 0x3) | ((data as u16) << 2);
|
|
},
|
|
0x25 => {
|
|
self.timer_a = (self.timer_a & 0xFFFC) | ((data as u16) & 0x03);
|
|
},
|
|
0x26 => {
|
|
self.timer_b = data;
|
|
},
|
|
0x27 => {
|
|
//if (data >> 5) & 0x1 {
|
|
// self.timer_b
|
|
},
|
|
|
|
0x28 => {
|
|
let ch = (data as usize) & 0x07;
|
|
self.channels[ch].next_on_state = data >> 4;
|
|
self.channels[ch].reset();
|
|
},
|
|
|
|
0x2a => {
|
|
if self.dac.enabled {
|
|
for _ in 0..3 {
|
|
self.dac.add_sample(((data as f32 - 128.0) / 255.0) * 2.0);
|
|
}
|
|
}
|
|
},
|
|
|
|
0x2b => {
|
|
self.dac.enabled = data & 0x80 != 0;
|
|
},
|
|
|
|
reg if is_reg_range(reg, 0x30) => {
|
|
let (ch, op) = get_ch_op(bank, reg);
|
|
let multiplier = if data == 0 { 0.5 } else { (data & 0x0F) as f32 };
|
|
let frequency = self.channels[ch].base_frequency;
|
|
debug!("{}: channel {} operator {} set to multiplier {}", DEV_NAME, ch + 1, op + 1, multiplier);
|
|
self.channels[ch].operators[op].set_multiplier(frequency, multiplier)
|
|
},
|
|
|
|
reg if is_reg_range(reg, 0x40) => {
|
|
let (ch, op) = get_ch_op(bank, reg);
|
|
// 0-127 is the attenuation, where 0 is the highest volume and 127 is the lowest, in 0.75 dB intervals
|
|
self.channels[ch].operators[op].set_total_level((data & 0x7F) as f32 * 0.75);
|
|
},
|
|
|
|
reg if is_reg_range(reg, 0x50)
|
|
|| is_reg_range(reg, 0x60)
|
|
|| is_reg_range(reg, 0x70)
|
|
|| is_reg_range(reg, 0x80)
|
|
|| is_reg_range(reg, 0x90)
|
|
=> {
|
|
let (ch, op) = get_ch_op(bank, reg);
|
|
self.update_rates(ch, op);
|
|
},
|
|
|
|
reg if (0xA0..=0xA2).contains(®) => {
|
|
let ch = get_ch(bank, reg);
|
|
self.channel_frequencies[ch].1 = (self.channel_frequencies[ch].1 & 0xFF00) | data as u16;
|
|
|
|
let frequency = fnumber_to_frequency(self.channel_frequencies[ch]);
|
|
debug!("{}: channel {} set to frequency {}", DEV_NAME, ch + 1, frequency);
|
|
self.channels[ch].set_frequency(frequency);
|
|
},
|
|
|
|
reg if (0xA4..=0xA6).contains(®) => {
|
|
let ch = ((reg as usize) & 0x07) - 4 + ((bank as usize) * 3);
|
|
self.channel_frequencies[ch].1 = (self.channel_frequencies[ch].1 & 0xFF) | ((data as u16) & 0x07) << 8;
|
|
self.channel_frequencies[ch].0 = (data & 0x38) >> 3;
|
|
},
|
|
|
|
reg if (0xB0..=0xB2).contains(®) => {
|
|
let ch = get_ch(bank, reg);
|
|
self.channels[ch].algorithm = match data & 0x07 {
|
|
0 => OperatorAlgorithm::A0,
|
|
1 => OperatorAlgorithm::A1,
|
|
2 => OperatorAlgorithm::A2,
|
|
3 => OperatorAlgorithm::A3,
|
|
4 => OperatorAlgorithm::A4,
|
|
5 => OperatorAlgorithm::A5,
|
|
6 => OperatorAlgorithm::A6,
|
|
7 => OperatorAlgorithm::A7,
|
|
_ => OperatorAlgorithm::A0,
|
|
};
|
|
},
|
|
|
|
_ => {
|
|
warn!("{}: !!! unhandled write to register {:0x} with {:0x}", DEV_NAME, reg, data);
|
|
},
|
|
}
|
|
}
|
|
|
|
fn update_rates(&mut self, ch: usize, op: usize) {
|
|
let index = get_index(ch, op);
|
|
let keycode = self.registers[0xA0 + get_ch_index(ch)] >> 1;
|
|
let rate_scaling = self.registers[0x50 + index] & 0xC0 >> 6;
|
|
let attack_rate = self.registers[0x50 + index] & 0x1F;
|
|
let first_decay_rate = self.registers[0x60 + index] & 0x1F;
|
|
let first_decay_level = (self.registers[0x80 + index] & 0x0F) >> 4;
|
|
let second_decay_rate = self.registers[0x70 + index] & 0x1F;
|
|
let release_rate = self.registers[0x80 + index] & 0x0F;
|
|
|
|
self.channels[ch].operators[op].set_attack_rate(calculate_rate(attack_rate, rate_scaling, keycode));
|
|
self.channels[ch].operators[op].set_first_decay_rate(calculate_rate(first_decay_rate, rate_scaling, keycode));
|
|
self.channels[ch].operators[op].set_first_decay_level(calculate_rate(first_decay_level, rate_scaling, keycode));
|
|
self.channels[ch].operators[op].set_second_decay_rate(calculate_rate(second_decay_rate, rate_scaling, keycode));
|
|
self.channels[ch].operators[op].set_release_rate(calculate_rate(release_rate, rate_scaling, keycode));
|
|
}
|
|
}
|
|
|
|
#[inline]
|
|
fn fnumber_to_frequency(fnumber: (u8, u16)) -> f32 {
|
|
(fnumber.1 as f32 * 0.0264) * 2_u32.pow(fnumber.0 as u32) as f32
|
|
}
|
|
|
|
#[inline]
|
|
fn calculate_rate(rate: u8, rate_scaling: u8, keycode: u8) -> usize {
|
|
let scale = match rate_scaling {
|
|
0 => 8,
|
|
1 => 4,
|
|
2 => 2,
|
|
3 => 1,
|
|
_ => 8, // this shouldn't be possible
|
|
};
|
|
|
|
(2 * rate as usize + (keycode as usize / scale)).min(64)
|
|
}
|
|
|
|
#[inline]
|
|
fn is_reg_range(reg: u8, base: u8) -> bool {
|
|
// There is no 4th channel in each of the groupings
|
|
reg >= base && reg <= base + 0x0F && (reg & 0x03) != 0x03
|
|
}
|
|
|
|
/// Get the channel and operator to target with a given register number
|
|
/// and bank number. Bank 0 refers to operators for channels 1-3, and
|
|
/// bank 1 refers to operators for channels 4-6.
|
|
#[inline]
|
|
fn get_ch_op(bank: u8, reg: u8) -> (usize, usize) {
|
|
let ch = ((reg as usize) & 0x03) + ((bank as usize) * 3);
|
|
let op = ((reg as usize) & 0x0C) >> 2;
|
|
(ch, op)
|
|
}
|
|
|
|
#[inline]
|
|
fn get_index(ch: usize, op: usize) -> usize {
|
|
let (bank, ch_l) = if ch < 3 { (0, ch) } else { (1, ch - 3) };
|
|
(bank << 8) | op << 2 | ch
|
|
}
|
|
|
|
#[inline]
|
|
fn get_ch(bank: u8, reg: u8) -> usize {
|
|
((reg as usize) & 0x07) + ((bank as usize) * 3)
|
|
}
|
|
|
|
#[inline]
|
|
fn get_ch_index(ch: usize) -> usize {
|
|
if ch < 3 {
|
|
ch
|
|
} else {
|
|
0x100 + ch - 3
|
|
}
|
|
}
|
|
|
|
|
|
impl Steppable for Ym2612 {
|
|
fn step(&mut self, system: &System) -> Result<ClockElapsed, Error> {
|
|
let rate = self.source.samples_per_second();
|
|
let available = self.source.space_available();
|
|
let samples = if available < rate / 1000 { available } else { rate / 1000 };
|
|
let nanos_per_sample = 1_000_000_000 / rate;
|
|
|
|
//if self.source.space_available() >= samples {
|
|
let mut buffer = vec![0.0; samples];
|
|
for (i, buffered_sample) in buffer.iter_mut().enumerate().take(samples) {
|
|
let event_clock = (system.clock + (i * nanos_per_sample) as Clock) / self.event_clock_period;
|
|
let mut sample = 0.0;
|
|
|
|
for ch in 0..6 {
|
|
sample += self.channels[ch].get_sample(event_clock);
|
|
}
|
|
|
|
if self.dac.enabled {
|
|
sample += self.dac.get_sample();
|
|
} else {
|
|
sample += self.channels[6].get_sample(event_clock);
|
|
}
|
|
|
|
*buffered_sample = sample.clamp(-1.0, 1.0);
|
|
}
|
|
self.source.write_samples(system.clock, &buffer);
|
|
//}
|
|
|
|
Ok(1_000_000) // Every 1ms of simulated time
|
|
}
|
|
}
|
|
|
|
impl Addressable for Ym2612 {
|
|
fn len(&self) -> usize {
|
|
0x04
|
|
}
|
|
|
|
fn read(&mut self, addr: Address, data: &mut [u8]) -> Result<(), Error> {
|
|
match addr {
|
|
0 | 1 | 2 | 3 => {
|
|
// Read the status byte (busy/overflow)
|
|
data[0] = ((self.timer_a_overflow as u8) << 1) | (self.timer_b_overflow as u8);
|
|
}
|
|
_ => {
|
|
warn!("{}: !!! unhandled read from {:0x}", DEV_NAME, addr);
|
|
},
|
|
}
|
|
debug!("{}: read from register {:x} of {:?}", DEV_NAME, addr, data);
|
|
Ok(())
|
|
}
|
|
|
|
fn write(&mut self, addr: Address, data: &[u8]) -> Result<(), Error> {
|
|
debug!("{}: write to register {:x} with {:x}", DEV_NAME, addr, data[0]);
|
|
match addr {
|
|
0 => {
|
|
self.selected_reg_0 = NonZeroU8::new(data[0]);
|
|
},
|
|
1 => {
|
|
if let Some(reg) = self.selected_reg_0 {
|
|
self.set_register(0, reg.get(), data[0]);
|
|
}
|
|
},
|
|
2 => {
|
|
self.selected_reg_1 = NonZeroU8::new(data[0]);
|
|
},
|
|
3 => {
|
|
if let Some(reg) = self.selected_reg_1 {
|
|
self.set_register(1, reg.get(), data[0]);
|
|
}
|
|
},
|
|
_ => {
|
|
warn!("{}: !!! unhandled write {:0x} to {:0x}", DEV_NAME, data[0], addr);
|
|
},
|
|
}
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
impl Transmutable for Ym2612 {
|
|
fn as_addressable(&mut self) -> Option<&mut dyn Addressable> {
|
|
Some(self)
|
|
}
|
|
|
|
fn as_steppable(&mut self) -> Option<&mut dyn Steppable> {
|
|
Some(self)
|
|
}
|
|
}
|
|
|