// license:BSD-3-Clause // copyright-holders:Miodrag Milanovic /*************************************************************************** audio/special.cpp Functions to emulate sound hardware of Specialist MX ( based on code of DAI interface ) ****************************************************************************/ #include "emu.h" #include "special.h" // device type definition DEFINE_DEVICE_TYPE(SPECIMX_SND, specimx_sound_device, "specimx_sound", "Specialist MX Custom Sound") //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // specimx_sound_device - constructor //------------------------------------------------- specimx_sound_device::specimx_sound_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, SPECIMX_SND, tag, owner, clock) , device_sound_interface(mconfig, *this) , m_mixer_channel(nullptr) , m_specimx_input{ 0, 0, 0 } { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void specimx_sound_device::device_start() { m_specimx_input[0] = m_specimx_input[1] = m_specimx_input[2] = 0; m_mixer_channel = stream_alloc(0, 1, machine().sample_rate()); } //------------------------------------------------- // sound_stream_update - handle a stream update //------------------------------------------------- void specimx_sound_device::sound_stream_update(sound_stream &stream, std::vector const &inputs, std::vector &outputs) { auto &sample_left = outputs[0]; stream_buffer::sample_t channel_0_signal = m_specimx_input[0] ? 0.1 : -0.1; stream_buffer::sample_t channel_1_signal = m_specimx_input[1] ? 0.1 : -0.1; stream_buffer::sample_t channel_2_signal = m_specimx_input[2] ? 0.1 : -0.1; stream_buffer::sample_t sum = channel_0_signal + channel_1_signal + channel_2_signal; sample_left.fill(sum); } //------------------------------------------------- // PIT callbacks //------------------------------------------------- WRITE_LINE_MEMBER(specimx_sound_device::set_input_ch0) { m_mixer_channel->update(); m_specimx_input[0] = state; } WRITE_LINE_MEMBER(specimx_sound_device::set_input_ch1) { m_mixer_channel->update(); m_specimx_input[1] = state; } WRITE_LINE_MEMBER(specimx_sound_device::set_input_ch2) { m_mixer_channel->update(); m_specimx_input[2] = state; }