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-rw-r--r--trunk/src/emu/sound/awacs.c175
1 files changed, 175 insertions, 0 deletions
diff --git a/trunk/src/emu/sound/awacs.c b/trunk/src/emu/sound/awacs.c
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index 00000000000..fda9f1ae8b6
--- /dev/null
+++ b/trunk/src/emu/sound/awacs.c
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+/***************************************************************************
+
+ awacs.c
+
+ AWACS/Singer style 16-bit audio I/O for '040 and PowerPC Macs
+
+ Emulation by R. Belmont
+
+***************************************************************************/
+
+#include "emu.h"
+#include "awacs.h"
+
+// device type definition
+const device_type AWACS = &device_creator<awacs_device>;
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// awacs_device - constructor
+//-------------------------------------------------
+
+awacs_device::awacs_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, AWACS, "AWACS", tag, owner, clock),
+ device_sound_interface(mconfig, *this)
+{
+}
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void awacs_device::device_start()
+{
+ // create the stream
+ m_stream = machine().sound().stream_alloc(*this, 0, 2, 22050, this);
+
+ memset(m_regs, 0, sizeof(m_regs));
+
+ m_timer = timer_alloc(0, NULL);
+
+ save_item(NAME(m_play_ptr));
+ save_item(NAME(m_buffer_size));
+ save_item(NAME(m_playback_enable));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void awacs_device::device_reset()
+{
+ m_stream->update();
+
+ memset(m_regs, 0, sizeof(m_regs));
+
+ m_play_ptr = 0;
+ m_buffer_size = 0;
+ m_playback_enable = false;
+ m_dma_space = NULL;
+ m_dma_offset_0 = m_dma_offset_1 = 0;
+ m_buffer_num = 0;
+}
+
+//-------------------------------------------------
+// device_timer - called when our device timer expires
+//-------------------------------------------------
+
+void awacs_device::device_timer(emu_timer &timer, device_timer_id tid, int param, void *ptr)
+{
+ m_stream->update();
+}
+
+//-------------------------------------------------
+// sound_stream_update - handle update requests for
+// our sound stream
+//-------------------------------------------------
+
+void awacs_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples)
+{
+ stream_sample_t *outL, *outR;
+ int offset = (m_buffer_num == 0) ? m_dma_offset_0 : m_dma_offset_1;
+
+ outL = outputs[0];
+ outR = outputs[1];
+
+ if (m_playback_enable)
+ {
+ for (int i = 0; i < samples; i++)
+ {
+ outL[i] = (INT16)m_dma_space->read_word(offset + m_play_ptr);
+ outR[i] = (INT16)m_dma_space->read_word(offset + m_play_ptr + 2);
+ m_play_ptr += 4;
+ }
+
+ // out of buffer?
+ if (m_play_ptr >= m_buffer_size)
+ {
+ UINT8 bufflag[2] = { 0x40, 0x80 };
+
+ m_regs[0x18] |= bufflag[m_buffer_num];
+ m_buffer_num ^= 1;
+ m_play_ptr = 0;
+ }
+ }
+ else
+ {
+ for (int i = 0; i < samples; i++)
+ {
+ outL[i] = 0;
+ outR[i] = 0;
+ }
+ }
+}
+
+//-------------------------------------------------
+// read - read from the chip's registers and internal RAM
+//-------------------------------------------------
+
+READ8_MEMBER( awacs_device::read )
+{
+ return m_regs[offset];
+}
+
+//-------------------------------------------------
+// write - write to the chip's registers and internal RAM
+//-------------------------------------------------
+
+WRITE8_MEMBER( awacs_device::write )
+{
+ switch (offset)
+ {
+ case 0x8:
+ case 0x9:
+ m_regs[offset] = data;
+ m_buffer_size = (m_regs[8]<<6) | (m_regs[9]>>2);
+// printf("buffer size = %x samples, %x bytes\n", m_buffer_size, m_buffer_size*4);
+ m_buffer_size *= 4; // samples * 16 bits * stereo
+ break;
+
+ case 0x10:
+ {
+ static const int rates[4] = { 22100, 29400, 44100, 22100 };
+ m_stream->set_sample_rate(rates[(data>>1)&3]);
+// printf("rate %d, enable: %d\n", rates[(data>>1)&3], data & 1);
+ m_playback_enable = (data & 1) ? true : false;
+
+ if (m_playback_enable && !(m_regs[0x10]&1))
+ {
+ m_play_ptr = 0;
+ m_buffer_num = 0;
+ }
+ }
+ break;
+
+ case 0x18:
+ m_regs[offset] &= 0xf0;
+ m_regs[offset] |= (data & 0x0f);
+ m_regs[offset] &= ~(data & 0xf0);
+ return;
+ }
+
+ m_regs[offset] = data;
+}
+
+void awacs_device::set_dma_base(address_space *space, int offset0, int offset1)
+{
+ m_dma_space = space;
+ m_dma_offset_0 = offset0;
+ m_dma_offset_1 = offset1;
+}
+