// license:BSD-3-Clause
// copyright-holders:Angelo Salese
/***************************************************************************
Flower custom sound chip
Similar to Wiping and Namco 15xx designs
TODO:
- several unknown registers (effects and unknown register tied to repeat port);
- repeat certainly needs a cutoff, which is unknown about how it works;
***************************************************************************/
#include "emu.h"
#include "flower.h"
//**************************************************************************
// GLOBAL VARIABLES
//**************************************************************************
// device type definition
DEFINE_DEVICE_TYPE(FLOWER_CUSTOM, flower_sound_device, "flower_sound", "Flower Custom Sound")
// TODO: select() unsupported by DEVICE_ADDRESS_MAP, so we need a trampoline here
void flower_sound_device::regs_map(address_map &map)
{
map(0x00, 0x03).select(0x38).w(FUNC(flower_sound_device::frequency_w));
map(0x04, 0x04).select(0x38).w(FUNC(flower_sound_device::repeat_w));
map(0x05, 0x05).select(0x38).w(FUNC(flower_sound_device::unk_w));
map(0x07, 0x07).select(0x38).w(FUNC(flower_sound_device::volume_w));
map(0x40, 0x45).select(0x38).w(FUNC(flower_sound_device::start_address_w));
map(0x47, 0x47).select(0x38).w(FUNC(flower_sound_device::sample_trigger_w));
}
//**************************************************************************
// LIVE DEVICE
//**************************************************************************
//-------------------------------------------------
// flower_sound_device - constructor
//-------------------------------------------------
flower_sound_device::flower_sound_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
: device_t(mconfig, FLOWER_CUSTOM, tag, owner, clock),
device_sound_interface(mconfig, *this),
device_memory_interface(mconfig, *this),
m_io_space_config("io", ENDIANNESS_LITTLE, 8, 7, 0, address_map_constructor(FUNC(flower_sound_device::regs_map), this)),
m_stream(nullptr),
m_mixer_lookup(nullptr),
m_last_channel(nullptr)
{
}
//-------------------------------------------------
// device_start - device-specific startup
//-------------------------------------------------
void flower_sound_device::device_start()
{
m_iospace = &space(AS_IO);
m_stream = stream_alloc(0, 1, clock()/2);
m_mixer_buffer.resize(clock()/50);
make_mixer_table(MAX_VOICES, defgain);
m_last_channel = m_channel_list + MAX_VOICES;
m_sample_rom = machine().root_device().memregion("samples")->base();
m_volume_rom = machine().root_device().memregion("soundvol")->base();
for (int i = 0; i < MAX_VOICES; i++)
{
save_item(NAME(m_channel_list[i].start_address), i);
save_item(NAME(m_channel_list[i].position), i);
save_item(NAME(m_channel_list[i].frequency), i);
save_item(NAME(m_channel_list[i].volume), i);
save_item(NAME(m_channel_list[i].volume_bank), i);
save_item(NAME(m_channel_list[i].effect), i);
save_item(NAME(m_channel_list[i].enable), i);
save_item(NAME(m_channel_list[i].repeat), i);
// assign a channel number (debugger aid)
m_channel_list[i].channel_number = i;
}
}
/* build a table to divide by the number of voices; gain is specified as gain*16 */
void flower_sound_device::make_mixer_table(int voices, int gain)
{
/* allocate memory */
m_mixer_table.resize(256 * voices);
/* find the middle of the table */
m_mixer_lookup = &m_mixer_table[128 * voices];
/* fill in the table - 16 bit case */
for (int i = 0; i < voices * 128; i++)
{
int val = i * gain * 16 / voices;
if (val > 32767) val = 32767;
m_mixer_lookup[ i] = val;
m_mixer_lookup[-i] = -val;
}
}
//-------------------------------------------------
// device_reset - device-specific reset
//-------------------------------------------------
void flower_sound_device::device_reset()
{
for (fl_sound_channel *voice = m_channel_list; voice < m_last_channel; voice++)
{
voice->start_address = 0;
voice->position = 0;
voice->volume = 0;
voice->enable = false;
voice->repeat = false;
}
}
void flower_sound_device::sound_stream_update(sound_stream &stream, std::vector<read_stream_view> const &inputs, std::vector<write_stream_view> &outputs)
{
auto &buffer = outputs[0];
short *mix;
uint8_t raw_sample;
std::fill_n(&m_mixer_buffer[0], buffer.samples(), 0);
for (fl_sound_channel *voice = m_channel_list; voice < m_last_channel; voice++)
{
int ch_volume = voice->volume;
int ch_frequency = voice->frequency;
if (voice->enable == false)
continue;
mix = &m_mixer_buffer[0];
for (int i = 0; i < buffer.samples(); i++)
{
if (voice->repeat == true)
{
raw_sample = m_sample_rom[((voice->start_address >> 7) & 0x7e00) | ((voice->position >> 7) & 0x1ff)];
// guess: cut off after a number of repetitions
if ((voice->position >> 7) & 0x20000)
{
voice->enable = false;
break;
}
}
else
{
raw_sample = m_sample_rom[((voice->start_address + voice->position) >> 7) & 0x7fff];
if (raw_sample == 0xff)
{
voice->enable = false;
break;
}
}
ch_volume |= voice->volume_bank;
*mix++ += m_volume_rom[(ch_volume << 8 | raw_sample) & 0x3fff] - 0x80;
voice->position += ch_frequency;
}
}
/* mix it down */
mix = &m_mixer_buffer[0];
for (int i = 0; i < buffer.samples(); i++)
buffer.put_int(i, m_mixer_lookup[*mix++], 32768);
}
//-------------------------------------------------
// memory_space_config - return a description of
// any address spaces owned by this device
//-------------------------------------------------
device_memory_interface::space_config_vector flower_sound_device::memory_space_config() const
{
return space_config_vector {
std::make_pair(AS_IO, &m_io_space_config)
};
}
//**************************************************************************
// READ/WRITE HANDLERS
//**************************************************************************
void flower_sound_device::lower_write(offs_t offset, uint8_t data)
{
m_stream->update();
m_iospace->write_byte(offset,data);
}
void flower_sound_device::upper_write(offs_t offset, uint8_t data)
{
m_stream->update();
m_iospace->write_byte(offset|0x40,data);
}
void flower_sound_device::frequency_w(offs_t offset, uint8_t data)
{
uint8_t ch = (offset >> 3) & 0x7;
fl_sound_channel *voice;
voice = &m_channel_list[ch];
voice->raw_frequency[offset & 3] = data & 0xf;
voice->frequency = voice->raw_frequency[2] << 12;
voice->frequency|= voice->raw_frequency[3] << 8;
voice->frequency|= voice->raw_frequency[0] << 4;
voice->frequency|= voice->raw_frequency[1] << 0;
}
void flower_sound_device::repeat_w(offs_t offset, uint8_t data)
{
uint8_t ch = (offset >> 3) & 0x7;
fl_sound_channel *voice;
voice = &m_channel_list[ch];
voice->repeat = BIT(data,4);
}
void flower_sound_device::unk_w(offs_t offset, uint8_t data)
{
// same as above?
}
void flower_sound_device::volume_w(offs_t offset, uint8_t data)
{
uint8_t ch = (offset >> 3) & 0x7;
fl_sound_channel *voice;
voice = &m_channel_list[ch];
voice->volume = data >> 4;
}
void flower_sound_device::start_address_w(offs_t offset, uint8_t data)
{
uint8_t ch = (offset >> 3) & 0x7;
fl_sound_channel *voice;
voice = &m_channel_list[ch];
voice->start_nibbles[offset & 7] = data & 0xf;
if ((offset & 7) == 4)
voice->effect = data >> 4;
}
void flower_sound_device::sample_trigger_w(offs_t offset, uint8_t data)
{
uint8_t ch = (offset >> 3) & 0x7;
fl_sound_channel *voice;
voice = &m_channel_list[ch];
voice->enable = true;
voice->volume_bank = (data & 3) << 4;
voice->start_address = 0;
voice->position = 0;
for (int i = 5; i >= 0; i--)
{
voice->start_address = (voice->start_address << 4) | voice->start_nibbles[i];
}
}