Sprinter/mame
2
0
Fork 0
mirror of https://github.com/holub/mame synced 2025-04-21 07:52:35 +03:00
Code Issues Actions 1 Packages Projects Releases Wiki Activity

scsp: improve handling of MIDI interrupts (#13521)

Browse Source
This commit is contained in:
Matthew Daniels 2025-03-26 07:18:44 +00:00 committed by GitHub
parent 9fd89a456e
commit d8f21c57f8
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 20 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
src/devices/sound/scsp.cpp
View File

@ -166,6 +166,7 @@ scsp_device::scsp_device(const machine_config &mconfig, const char *tag, device_
{
std::fill(std::begin(m_RINGBUF), std::end(m_RINGBUF), 0);
std::fill(std::begin(m_MidiStack), std::end(m_MidiStack), 0);
std::fill(std::begin(m_MidiOutStack), std::end(m_MidiOutStack), 0);
std::fill(std::begin(m_LPANTABLE), std::end(m_LPANTABLE), 0);
std::fill(std::begin(m_RPANTABLE), std::end(m_RPANTABLE), 0);
std::fill(std::begin(m_TimPris), std::end(m_TimPris), 0);
@ -243,6 +244,7 @@ void scsp_device::device_start()
save_item(NAME(m_IrqTimBC));
save_item(NAME(m_IrqMidi));
save_item(NAME(m_MidiOutStack));
save_item(NAME(m_MidiOutW));
save_item(NAME(m_MidiOutR));
save_item(NAME(m_MidiStack));
@ -359,7 +361,6 @@ void scsp_device::CheckPendingIRQ()
if (en & 8)
{
m_irq_cb(m_IrqMidi, ASSERT_LINE);
m_udata.data[0x20/2] &= ~8;
return;
}
@ -733,7 +734,7 @@ void scsp_device::UpdateReg(int reg)
break;
case 0x6:
case 0x7:
midi_in(m_udata.data[0x6/2] & 0xff);
midi_out_w(m_udata.data[0x6/2] & 0xff);
break;
case 8:
case 9:
@ -899,13 +900,17 @@ void scsp_device::UpdateRegR(int reg)
u16 v = m_udata.data[0x4/2];
v &= 0xff00;
v |= m_MidiStack[m_MidiR];
m_irq_cb(m_IrqMidi, CLEAR_LINE); // cancel the IRQ
logerror("Read %x from SCSP MIDI\n", v);
if (m_MidiR != m_MidiW)
{
++m_MidiR;
m_MidiR &= 31;
}
if (m_MidiR == m_MidiW) // if the input FIFO is empty, clear the IRQ
{
m_irq_cb(m_IrqMidi, CLEAR_LINE);
m_udata.data[0x20 / 2] &= ~8;
}
m_udata.data[0x4/2] = v;
}
break;
@ -1451,11 +1456,19 @@ void scsp_device::midi_in(u8 data)
u16 scsp_device::midi_out_r()
{
u8 val = m_MidiStack[m_MidiR++];
m_MidiR &= 31;
u8 val = m_MidiOutStack[m_MidiOutR++];
m_MidiOutR &= 31;
return val;
}
void scsp_device::midi_out_w(u8 data)
{
m_MidiOutStack[m_MidiOutW++] = data;
m_MidiOutW &= 31;
//CheckPendingIRQ();
}
//LFO handling
#define LFIX(v) ((u32) ((float) (1 << LFO_SHIFT) * (v)))

2
src/devices/sound/scsp.h
View File

@ -37,6 +37,7 @@ public:
// MIDI I/O access (used for comms on Model 2/3)
void midi_in(u8 data);
u16 midi_out_r();
void midi_out_w(u8 data);
protected:
// device-level overrides
@ -118,6 +119,7 @@ private:
u32 m_IrqTimBC;
u32 m_IrqMidi;
u8 m_MidiOutStack[32];
u8 m_MidiOutW, m_MidiOutR;
u8 m_MidiStack[32];
u8 m_MidiW, m_MidiR;