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troubleshooting, maybe fixed something

This commit is contained in:
Theron Spiegl 2019-12-31 19:32:00 -06:00
parent 24be0586e6
commit 73549d6c2d
1 changed files with 21 additions and 19 deletions
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40
src/apu/square.rs
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@ -9,14 +9,14 @@ pub struct Square {
pub sample: u16,
pub enabled: bool,
duty_cycle: [u8; 8],
duty_counter: usize,
duty_cycle: [u8; 8], // "sequencer", set to one of the lines in DUTY_CYCLE_SEQUENCES
duty_counter: usize, // current index within the duty_cycle
envelope: u16,
envelope_divider: u16,
decay_counter: u16,
envelope: u16, // constant volume/envelope period. reflects what was last written to $4000/$4004
envelope_divider: u16, //
decay_counter: u16, // remainder of envelope divider
constant_volume_flag: bool, // (0: use volume from envelope; 1: use constant volume)
start: bool,
start: bool, // restarts envelope
length_counter_halt: bool, // (this bit is also the envelope's loop flag)
pub length_counter: u8,
@ -107,16 +107,17 @@ impl Square {
// When the divider is clocked while at 0, it is loaded with V and clocks the decay level counter.
if self.envelope_divider == 0 {
self.envelope_divider = self.envelope;
// Then one of two actions occurs: If the counter is non-zero, it is decremented,
if self.decay_counter != 0 {
self.decay_counter -= 1;
} else if self.length_counter_halt {
// otherwise if the loop flag is set, the decay level counter is loaded with 15.
self.decay_counter = 15;
}
} else {
self.envelope_divider -= 1;
}
// Then one of two actions occurs: If the counter is non-zero, it is decremented,
if self.decay_counter != 0 {
self.decay_counter -= 1;
// println!("decaying to {}", self.decay_counter);
} else if self.length_counter_halt {
// otherwise if the loop flag is set, the decay level counter is loaded with 15.
self.decay_counter = 15;
}
}
pub fn clock_length_counter(&mut self) {
@ -169,11 +170,12 @@ impl Square {
self.duty_cycle = DUTY_CYCLE_SEQUENCES[(value >> 6) as usize];
self.length_counter_halt = value & (1<<5) != 0;
self.constant_volume_flag = value & (1<<4) != 0;
self.envelope = if self.constant_volume_flag {
value as u16 & 0b1111
} else {
self.decay_counter
};
self.envelope = value as u16 & 0b1111;
// if self.constant_volume_flag {
// value as u16 & 0b1111
// } else {
// self.decay_counter
// };
}
// $4001/$4005
@ -199,7 +201,7 @@ impl Square {
// When the enabled bit is cleared (via $4015), the length counter is forced to 0 and cannot be changed until enabled is set again (the length counter's previous value is lost).
if self.enabled {
self.length_counter = super::LENGTH_COUNTER_TABLE[value as usize >> 3];
println!("val: 0b{:08b}, wrote length_counter {}", value, self.length_counter);
// println!("val: 0b{:08b}, wrote length_counter {}", value, self.length_counter);
}
let timer_high = value as u16 & 0b0000_0111;
self.timer_period &= 0b11111000_11111111; // mask off high 3 bits of 11-bit timer