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Diffstat (limited to 'src/devices/bus/spectrum/uspeech.cpp')
-rw-r--r--src/devices/bus/spectrum/uspeech.cpp40
1 files changed, 27 insertions, 13 deletions
diff --git a/src/devices/bus/spectrum/uspeech.cpp b/src/devices/bus/spectrum/uspeech.cpp
index 87f66ca0182..60374fd3c2c 100644
--- a/src/devices/bus/spectrum/uspeech.cpp
+++ b/src/devices/bus/spectrum/uspeech.cpp
@@ -76,6 +76,7 @@ spectrum_uspeech_device::spectrum_uspeech_device(const machine_config &mconfig,
void spectrum_uspeech_device::device_start()
{
+ save_item(NAME(m_romcs));
}
@@ -98,46 +99,59 @@ READ_LINE_MEMBER(spectrum_uspeech_device::romcs)
return m_romcs;
}
-
-READ8_MEMBER(spectrum_uspeech_device::mreq_r)
+void spectrum_uspeech_device::opcode_fetch(offs_t offset)
{
- uint8_t data;
+ if (!machine().side_effects_disabled() && (offset == 0x0038))
+ {
+ m_romcs = !m_romcs;
+ }
+}
- if (!machine().side_effects_disabled() && (offset == 0x38))
+uint8_t spectrum_uspeech_device::iorq_r(offs_t offset)
+{
+ if (!machine().side_effects_disabled() && (offset == 0x0038))
{
m_romcs = !m_romcs;
}
- switch (offset)
+ return 0xff;
+}
+
+uint8_t spectrum_uspeech_device::mreq_r(offs_t offset)
+{
+ uint8_t data = 0xff;
+
+ switch (offset & 0xf000)
{
- case 0x1000:
- data = !m_nsp->lrq_r(); // (m_nsp->lrq_r() && (m_nsp->sby_r() != 0)) ? 0x00 : 0x01;
- break;
- default:
+ case 0x0000:
data = m_rom->base()[offset & 0x7ff];
break;
+ case 0x1000:
+ data = !m_nsp->lrq_r();
+ break;
}
return data;
}
-WRITE8_MEMBER(spectrum_uspeech_device::mreq_w)
+void spectrum_uspeech_device::mreq_w(offs_t offset, uint8_t data)
{
- switch (offset)
+ switch (offset & 0xf001)
{
case 0x1000:
+ case 0x1001:
// allophone
m_nsp->ald_w(data & 0x3f);
break;
case 0x3000:
// intonation low
- m_nsp->set_clock(3500000); // CK / 4 ??
+ m_nsp->set_clock(3050000); // oscillator frequency read from hardware
break;
case 0x3001:
// intonation high
- m_nsp->set_clock(3800000); // TODO: the exact frequency is unknown
+ m_nsp->set_clock(3260000); // oscillator frequency read from hardware
break;
}
}