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Diffstat (limited to 'src/devices/sound/tms3615.cpp')
-rw-r--r--src/devices/sound/tms3615.cpp109
1 files changed, 109 insertions, 0 deletions
diff --git a/src/devices/sound/tms3615.cpp b/src/devices/sound/tms3615.cpp
new file mode 100644
index 00000000000..3ccf9159b9d
--- /dev/null
+++ b/src/devices/sound/tms3615.cpp
@@ -0,0 +1,109 @@
+// license:BSD-3-Clause
+// copyright-holders:Juergen Buchmueller
+#include "emu.h"
+#include "tms3615.h"
+
+#define VMIN 0x0000
+#define VMAX 0x7fff
+
+static const int divisor[TMS3615_TONES] = { 478, 451, 426, 402, 379, 358, 338, 319, 301, 284, 268, 253, 239 };
+
+
+// device type definition
+const device_type TMS3615 = &device_creator<tms3615_device>;
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// tms3615_device - constructor
+//-------------------------------------------------
+
+tms3615_device::tms3615_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, TMS3615, "TMS3615", tag, owner, clock, "tms3615", __FILE__),
+ device_sound_interface(mconfig, *this),
+ m_channel(0),
+ m_samplerate(0),
+ m_basefreq(0),
+ m_output8(0),
+ m_output16(0),
+ m_enable(0)
+{
+ memset(m_counter8, 0, TMS3615_TONES);
+ memset(m_counter16, 0, TMS3615_TONES);
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void tms3615_device::device_start()
+{
+ m_channel = stream_alloc(0, 2, clock()/8);
+ m_samplerate = clock()/8;
+ m_basefreq = clock();
+}
+
+
+//-------------------------------------------------
+// sound_stream_update - handle a stream update
+//-------------------------------------------------
+
+void tms3615_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples)
+{
+ int samplerate = m_samplerate;
+ stream_sample_t *buffer8 = outputs[TMS3615_FOOTAGE_8];
+ stream_sample_t *buffer16 = outputs[TMS3615_FOOTAGE_16];
+
+ while( samples-- > 0 )
+ {
+ int sum8 = 0, sum16 = 0, tone = 0;
+
+ for (tone = 0; tone < TMS3615_TONES; tone++)
+ {
+ // 8'
+
+ m_counter8[tone] -= (m_basefreq / divisor[tone]);
+
+ while( m_counter8[tone] <= 0 )
+ {
+ m_counter8[tone] += samplerate;
+ m_output8 ^= 1 << tone;
+ }
+
+ if (m_output8 & m_enable & (1 << tone))
+ {
+ sum8 += VMAX;
+ }
+
+ // 16'
+
+ m_counter16[tone] -= (m_basefreq / divisor[tone] / 2);
+
+ while( m_counter16[tone] <= 0 )
+ {
+ m_counter16[tone] += samplerate;
+ m_output16 ^= 1 << tone;
+ }
+
+ if (m_output16 & m_enable & (1 << tone))
+ {
+ sum16 += VMAX;
+ }
+ }
+
+ *buffer8++ = sum8 / TMS3615_TONES;
+ *buffer16++ = sum16 / TMS3615_TONES;
+ }
+
+ m_enable = 0;
+}
+
+
+void tms3615_device::enable_w(int enable)
+{
+ m_enable = enable;
+}