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-rw-r--r--trunk/src/emu/sound/tc8830f.c209
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diff --git a/trunk/src/emu/sound/tc8830f.c b/trunk/src/emu/sound/tc8830f.c
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+/***************************************************************************
+
+ tc8830f.c - Toshiba TC8830F, CMOS voice recording/reproducing LSI
+ 1-bit ADM (Adaptive Delta Modulation), similar to TC8801 and T6668.
+
+ Very preliminary...
+
+ TODO:
+ - ADM decoder
+ - remaining commands
+ - manual control
+ - chip read
+ - RAM
+ - recording
+
+***************************************************************************/
+
+#include "emu.h"
+#include "tc8830f.h"
+
+
+// device type definition
+const device_type TC8830F = &device_creator<tc8830f_device>;
+
+tc8830f_device::tc8830f_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, TC8830F, "TC8830F", tag, owner, clock),
+ device_sound_interface(mconfig, *this)
+{
+}
+
+
+void tc8830f_device::device_start()
+{
+ // create the stream
+ m_stream = machine().sound().stream_alloc(*this, 0, 1, clock() / 0x10, this);
+
+ m_mem_base = (UINT8 *)device().machine().root_device().memregion(":tc8830f")->base();
+ m_mem_mask = device().machine().root_device().memregion(":tc8830f")->bytes() - 1;
+
+ // register for savestates
+ save_item(NAME(m_playing));
+ save_item(NAME(m_address));
+ save_item(NAME(m_stop_address));
+ save_item(NAME(m_bitcount));
+ save_item(NAME(m_bitrate));
+ save_item(NAME(m_command));
+ save_item(NAME(m_cmd_rw));
+ save_item(NAME(m_phrase));
+
+ reset();
+}
+
+
+void tc8830f_device::device_post_load()
+{
+ device_clock_changed();
+}
+
+
+void tc8830f_device::device_clock_changed()
+{
+ int divisor = 0x10 * (4 - (m_bitrate & 3));
+ m_stream->set_sample_rate(clock() / divisor);
+}
+
+
+
+void tc8830f_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples)
+{
+ for (int i = 0; i < samples; i++)
+ {
+ int mix = 0;
+ if (m_playing)
+ {
+ // get bit
+ int bit = m_mem_base[m_address] >> m_bitcount & 1;
+ m_bitcount = (m_bitcount + 1) & 7;
+ if (m_bitcount == 0)
+ {
+ m_address = (m_address + 1) & m_mem_mask;
+ if (m_address == m_stop_address)
+ m_playing = false;
+ }
+
+ // compute sample
+ // this is a placeholder until ADM is implemented
+ mix = bit * 0x7fff;
+ }
+ outputs[0][i] = mix;
+ }
+}
+
+
+void tc8830f_device::reset()
+{
+ m_stream->update();
+
+ m_playing = false;
+ m_address = 0x100;
+ m_bitcount = 0;
+ m_cmd_rw = 0;
+
+ // in cpu control, enter play mode and reset bitrate
+ write_p(1);
+ write_p(6);
+ write_p(0);
+}
+
+
+void tc8830f_device::write_p(UINT8 data)
+{
+ m_stream->update();
+ data &= 0xf;
+
+ if (m_cmd_rw == 0)
+ {
+ // select command
+ m_command = data;
+ switch (m_command)
+ {
+ // immediate commands
+ case 0x1:
+ break;
+
+ case 0x2:
+ m_playing = true;
+ break;
+
+ case 0x3:
+ m_playing = false;
+ break;
+
+ // multi-nibble commands
+ case 0x4: case 0x5: case 0x6: case 0x7:
+ m_cmd_rw = 1;
+ break;
+
+ case 0x8: case 0x9: case 0xa: case 0xb:
+ logerror("tc8830f: Unemulated command %X\n", m_command);
+ break;
+
+ default:
+ logerror("tc8830f: Invalid command %X\n", m_command);
+ break;
+ }
+ }
+
+ else
+ {
+ // write command
+ switch (m_command)
+ {
+ case 0x4:
+ // ADLD1: set address counter
+ m_address = (m_address & ~(0xf << (m_cmd_rw*4))) | (data << (m_cmd_rw*4));
+ if (m_cmd_rw == 5)
+ {
+ m_address &= m_mem_mask;
+ m_bitcount = 0;
+ m_cmd_rw = -1;
+ }
+ break;
+
+ case 0x5:
+ // ADLD2: set address stop
+ m_stop_address = (m_stop_address & ~(0xf << (m_cmd_rw*4))) | (data << (m_cmd_rw*4));
+ if (m_cmd_rw == 5)
+ {
+ m_stop_address &= m_mem_mask;
+ m_cmd_rw = -1;
+ }
+ break;
+
+ case 0x6:
+ // CNDT: d0-d1: bitrate, d2: enable overflow
+ m_bitrate = data & 3;
+ device_clock_changed();
+ m_cmd_rw = -1;
+ break;
+
+ case 0x7:
+ // LABEL: set phrase
+ if (m_cmd_rw == 1)
+ {
+ m_phrase = (m_phrase & 0x30) | data;
+ }
+ else
+ {
+ m_phrase = (m_phrase & 0x0f) | (data << 4 & 0x30);
+
+ // update addresses and start
+ UINT8 offs = m_phrase * 4;
+ m_address = (m_mem_base[offs] | m_mem_base[offs|1]<<8 | m_mem_base[offs|2]<<16) & m_mem_mask;
+ offs += 4;
+ m_stop_address = (m_mem_base[offs] | m_mem_base[offs|1]<<8 | m_mem_base[offs|2]<<16) & m_mem_mask;
+
+ m_bitcount = 0;
+ m_playing = true;
+ m_cmd_rw = -1;
+ }
+ break;
+
+ default:
+ m_cmd_rw = -1;
+ break;
+ }
+ m_cmd_rw++;
+ }
+}