paoda
/
gb
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

fix(apu): disable channel if DAC is disabled

This commit is contained in:
Rekai Nyangadzayi Musuka 2021-08-17 20:42:41 -05:00
parent aa22e93049
commit b9046bceba
1 changed files with 27 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
src/apu.rs
View File

@ -456,7 +456,11 @@ impl Channel1 {
/// 0xFF12 | NR12 - Channel 1 Volume Envelope
pub(crate) fn set_envelope(&mut self, byte: u8) {
self.envelope = byte.into()
self.envelope = byte.into();
if !self.is_dac_enabled() {
self.enabled = false;
}
}
/// 0xFF13 | NR13 - Channel 1 Frequency low (lower 8 bits only)
@ -529,6 +533,10 @@ impl Channel1 {
fn frequency(&self) -> u16 {
(self.freq_hi.freq_bits() as u16) << 8 | self.freq_lo as u16
}
fn is_dac_enabled(&self) -> bool {
self.envelope.0 & 0xF8 != 0x00
}
}
#[derive(Debug, Default)]
@ -591,7 +599,11 @@ impl Channel2 {
/// 0xFF17 | NR22 - Channel 2 Volume ENvelope
pub(crate) fn set_envelope(&mut self, byte: u8) {
self.envelope = byte.into()
self.envelope = byte.into();
if !self.is_dac_enabled() {
self.enabled = false;
}
}
/// 0xFF18 | NR23 - Channel 2 Frequency low (lower 8 bits only)
@ -625,6 +637,10 @@ impl Channel2 {
fn frequency(&self) -> u16 {
(self.freq_hi.freq_bits() as u16) << 8 | self.freq_lo as u16
}
fn is_dac_enabled(&self) -> bool {
self.envelope.0 & 0xF8 != 0x00
}
}
#[derive(Debug, Default)]
@ -803,7 +819,11 @@ impl Channel4 {
/// 0xFF21 | NR42 - Channel 4 Volume Envelope
pub(crate) fn set_envelope(&mut self, byte: u8) {
self.envelope = byte.into()
self.envelope = byte.into();
if !self.is_dac_enabled() {
self.enabled = false;
}
}
/// 0xFF22 | NR43 - Chanel 4 Polynomial Counter
@ -866,6 +886,10 @@ impl Channel4 {
}
}
fn is_dac_enabled(&self) -> bool {
self.envelope.0 & 0xF8 != 0x00
}
fn divisor(code: u8) -> u8 {
if code == 0 {
return 8;