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Diffstat (limited to 'src/mess/audio/socrates.c')
-rw-r--r-- | src/mess/audio/socrates.c | 127 |
1 files changed, 0 insertions, 127 deletions
diff --git a/src/mess/audio/socrates.c b/src/mess/audio/socrates.c deleted file mode 100644 index c35896e5c25..00000000000 --- a/src/mess/audio/socrates.c +++ /dev/null @@ -1,127 +0,0 @@ -// license:BSD-3-Clause -// copyright-holders:Jonathan Gevaryahu -/*************************************************************************** - - audio/socrates.c - Copyright (C) 2010-2011 Jonathan Gevaryahu AKA Lord Nightmare - - This handles the two squarewaves (plus the one weird wave) channels - on the V-tech Socrates system 27-0769 ASIC. - - -****************************************************************************/ - -#include "emu.h" -#include "socrates.h" - - -// device type definition -const device_type SOCRATES_SOUND = &device_creator<socrates_snd_device>; - - -//------------------------------------------------- -// socrates_snd_device - constructor -//------------------------------------------------- - -socrates_snd_device::socrates_snd_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) - : device_t(mconfig, SOCRATES_SOUND, "Socrates Sound", tag, owner, clock, "socrates_snd", __FILE__), - device_sound_interface(mconfig, *this) -{ -} - - -//------------------------------------------------- -// device_start - device-specific startup -//------------------------------------------------- - -void socrates_snd_device::device_start() -{ - m_freq[0] = m_freq[1] = 0xff; /* channel 1,2 frequency */ - m_vol[0] = m_vol[1] = 0x07; /* channel 1,2 volume */ - m_enable[0] = m_enable[1] = 0x01; /* channel 1,2 enable */ - m_channel3 = 0x00; /* channel 3 weird register */ - m_DAC_output = 0x00; /* output */ - m_state[0] = m_state[1] = m_state[2] = 0; - m_accum[0] = m_accum[1] = m_accum[2] = 0xFF; - m_stream = machine().sound().stream_alloc(*this, 0, 1, clock() ? clock() : machine().sample_rate()); -} - - -//------------------------------------------------- -// sound_stream_update - handle a stream update -//------------------------------------------------- - -void socrates_snd_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples) -{ - for (int i = 0; i < samples; i++) - { - snd_clock(); - outputs[0][i] = ((int)m_DAC_output<<4); - } -} - - -const UINT8 socrates_snd_device::s_volumeLUT[16] = -{ -0, 61, 100, 132, 158, 183, 201, 218, -233, 242, 253, 255, 250, 240, 224, 211 -}; // this table is actually quite weird on the real console. -// 0, 0.033, 0.055, 0.07175, 0.086, 0.1, 0.11, 0.119, 0.127, 0.132, 0.138, 0.139, 0.136, 0.131, 0.122, 0.115 are the voltage amplitudes for the steps on channel 2. the last four are particularly bizarre, probably caused by some sort of internal clipping. - -void socrates_snd_device::snd_clock() /* called once per clock */ -{ - for (int channel = 0; channel < 2; channel++) - { - if ((m_accum[channel] == 0) && m_enable[channel]) - { - m_state[channel] = (m_state[channel]^0x1); - m_accum[channel] = m_freq[channel]; - } - else if (m_enable[channel]) - { - m_accum[channel]--; - } - else - { - m_accum[channel] = 0; // channel is disabled - m_state[channel] = 0; - } - } - // handle channel 3 here - m_DAC_output = (m_state[0]?(s_volumeLUT[m_vol[0]]*9.4):0); // channel 1 is ~2.4 times as loud as channel 2 - m_DAC_output += (m_state[1]?(s_volumeLUT[m_vol[1]]<<2):0); - // add channel 3 to dac output here -} - - -void socrates_snd_device::reg0_w(int data) -{ - m_stream->update(); - m_freq[0] = data; -} - -void socrates_snd_device::reg1_w(int data) -{ - m_stream->update(); - m_freq[1] = data; -} - -void socrates_snd_device::reg2_w(int data) -{ - m_stream->update(); - m_vol[0] = data&0xF; - m_enable[0] = (data&0x10)>>4; -} - -void socrates_snd_device::reg3_w(int data) -{ - m_stream->update(); - m_vol[1] = data&0xF; - m_enable[1] = (data&0x10)>>4; -} - -void socrates_snd_device::reg4_w(int data) -{ - m_stream->update(); - m_channel3 = data; -} |