diff options
Diffstat (limited to 'src/devices/sound/saa1099.cpp')
-rw-r--r-- | src/devices/sound/saa1099.cpp | 182 |
1 files changed, 79 insertions, 103 deletions
diff --git a/src/devices/sound/saa1099.cpp b/src/devices/sound/saa1099.cpp index b5566ab164f..dd5f6154afd 100644 --- a/src/devices/sound/saa1099.cpp +++ b/src/devices/sound/saa1099.cpp @@ -70,17 +70,19 @@ #include "emu.h" #include "saa1099.h" -#define LEFT 0x00 -#define RIGHT 0x01 +static constexpr int clock_divider = 256; -static constexpr int amplitude_lookup[16] = { +static constexpr int LEFT = 0x00; +static constexpr int RIGHT = 0x01; + +static constexpr u16 amplitude_lookup[16] = { 0*32767/16, 1*32767/16, 2*32767/16, 3*32767/16, 4*32767/16, 5*32767/16, 6*32767/16, 7*32767/16, 8*32767/16, 9*32767/16, 10*32767/16, 11*32767/16, 12*32767/16, 13*32767/16, 14*32767/16, 15*32767/16 }; -static constexpr uint8_t envelope[8][64] = { +static constexpr u8 envelope[8][64] = { /* zero amplitude */ { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, @@ -123,7 +125,6 @@ static constexpr uint8_t envelope[8][64] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15 } }; - // device type definition DEFINE_DEVICE_TYPE(SAA1099, saa1099_device, "saa1099", "Philips SAA1099") @@ -135,21 +136,20 @@ DEFINE_DEVICE_TYPE(SAA1099, saa1099_device, "saa1099", "Philips SAA1099") // saa1099_device - constructor //------------------------------------------------- -saa1099_device::saa1099_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) +saa1099_device::saa1099_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock) : device_t(mconfig, SAA1099, tag, owner, clock) , device_sound_interface(mconfig, *this) , m_stream(nullptr) , m_noise_params{ 0, 0 } - , m_env_enable{ 0, 0 } - , m_env_reverse_right{ 0, 0 } + , m_env_enable{ false, false } + , m_env_reverse_right{ false, false } , m_env_mode{ 0, 0 } - , m_env_bits{ 0, 0 } - , m_env_clock{ 0, 0 } + , m_env_bits{ false, false } + , m_env_clock{ false, false } , m_env_step{ 0, 0 } - , m_all_ch_enable(0) - , m_sync_state(0) + , m_all_ch_enable(false) + , m_sync_state(false) , m_selected_reg(0) - , m_sample_rate(0.0) { } @@ -160,12 +160,8 @@ saa1099_device::saa1099_device(const machine_config &mconfig, const char *tag, d void saa1099_device::device_start() { - /* copy global parameters */ - m_master_clock = clock(); - m_sample_rate = clock() / 256; - /* for each chip allocate one stream */ - m_stream = stream_alloc(0, 2, m_sample_rate); + m_stream = stream_alloc(0, 2, clock()/clock_divider); save_item(NAME(m_noise_params)); save_item(NAME(m_env_enable)); @@ -178,25 +174,18 @@ void saa1099_device::device_start() save_item(NAME(m_sync_state)); save_item(NAME(m_selected_reg)); - for (int i = 0; i < 6; i++) - { - save_item(NAME(m_channels[i].frequency), i); - save_item(NAME(m_channels[i].freq_enable), i); - save_item(NAME(m_channels[i].noise_enable), i); - save_item(NAME(m_channels[i].octave), i); - save_item(NAME(m_channels[i].amplitude), i); - save_item(NAME(m_channels[i].envelope), i); - save_item(NAME(m_channels[i].counter), i); - save_item(NAME(m_channels[i].freq), i); - save_item(NAME(m_channels[i].level), i); - } - - for (int i = 0; i < 2; i++) - { - save_item(NAME(m_noise[i].counter), i); - save_item(NAME(m_noise[i].freq), i); - save_item(NAME(m_noise[i].level), i); - } + save_item(STRUCT_MEMBER(m_channels, frequency)); + save_item(STRUCT_MEMBER(m_channels, freq_enable)); + save_item(STRUCT_MEMBER(m_channels, noise_enable)); + save_item(STRUCT_MEMBER(m_channels, octave)); + save_item(STRUCT_MEMBER(m_channels, amplitude)); + save_item(STRUCT_MEMBER(m_channels, envelope)); + save_item(STRUCT_MEMBER(m_channels, counter)); + save_item(STRUCT_MEMBER(m_channels, level)); + + save_item(STRUCT_MEMBER(m_noise, counter)); + save_item(STRUCT_MEMBER(m_noise, freq)); + save_item(STRUCT_MEMBER(m_noise, level)); } @@ -206,10 +195,7 @@ void saa1099_device::device_start() void saa1099_device::device_clock_changed() { - m_master_clock = clock(); - m_sample_rate = clock() / 256; - - m_stream->set_sample_rate(m_sample_rate); + m_stream->set_sample_rate(clock()/clock_divider); } @@ -217,50 +203,37 @@ void saa1099_device::device_clock_changed() // sound_stream_update - handle a stream update //------------------------------------------------- -void saa1099_device::sound_stream_update(sound_stream &stream, stream_sample_t **inputs, stream_sample_t **outputs, int samples) +void saa1099_device::sound_stream_update(sound_stream &stream) { int j, ch; /* if the channels are disabled we're done */ if (!m_all_ch_enable) - { - /* init output data */ - memset(outputs[LEFT],0,samples*sizeof(*outputs[LEFT])); - memset(outputs[RIGHT],0,samples*sizeof(*outputs[RIGHT])); return; - } for (ch = 0; ch < 2; ch++) { switch (m_noise_params[ch]) { - case 0: m_noise[ch].freq = m_master_clock/256.0 * 2; break; - case 1: m_noise[ch].freq = m_master_clock/512.0 * 2; break; - case 2: m_noise[ch].freq = m_master_clock/1024.0 * 2; break; - case 3: m_noise[ch].freq = m_channels[ch * 3].freq; break; // todo: this case will be m_master_clock/[ch*3's octave divisor, 0 is = 256*2, higher numbers are higher] * 2 if the tone generator phase reset bit (0x1c bit 1) is set. + case 0: + case 1: + case 2: m_noise[ch].freq = 256 << m_noise_params[ch]; break; + case 3: m_noise[ch].freq = m_channels[ch * 3].freq(); break; // todo: this case will be clock()/[ch*3's octave divisor, 0 is = 256*2, higher numbers are higher] * 2 if the tone generator phase reset bit (0x1c bit 1) is set. } } /* fill all data needed */ - for( j = 0; j < samples; j++ ) + for( j = 0; j < stream.samples(); j++ ) { int output_l = 0, output_r = 0; /* for each channel */ for (ch = 0; ch < 6; ch++) { - if (m_channels[ch].freq == 0.0) - m_channels[ch].freq = (double)((2 * m_master_clock / 512) << m_channels[ch].octave) / - (511.0 - (double)m_channels[ch].frequency); - /* check the actual position in the square wave */ - m_channels[ch].counter -= m_channels[ch].freq; - while (m_channels[ch].counter < 0) + while (m_channels[ch].counter <= 0) { /* calculate new frequency now after the half wave is updated */ - m_channels[ch].freq = (double)((2 * m_master_clock / 512) << m_channels[ch].octave) / - (511.0 - (double)m_channels[ch].frequency); - - m_channels[ch].counter += m_sample_rate; + m_channels[ch].counter += m_channels[ch].freq(); m_channels[ch].level ^= 1; /* eventually clock the envelope counters */ @@ -269,27 +242,40 @@ void saa1099_device::sound_stream_update(sound_stream &stream, stream_sample_t * if (ch == 4 && m_env_clock[1] == 0) envelope_w(1); } + m_channels[ch].counter -= clock_divider; + u8 level = 0; // output level (0...2, 0 = off, 1 = 100%, 2 = 50%) // if the noise is enabled + u8 noise_out = m_noise[ch/3].level & 1; // noise output (noise 0: chan 0-2, noise 1: chan 3-5) + u8 tone_out = m_channels[ch].level & 1; // tone output if (m_channels[ch].noise_enable) { - // if the noise level is high (noise 0: chan 0-2, noise 1: chan 3-5) - if (m_noise[ch/3].level & 1) + // if both noise and square wave are enabled, output is tone output + if (m_channels[ch].freq_enable) + { + // half amplitude if the noise level is high + if (noise_out) + level = tone_out << 1; + else + level = tone_out; + } + else { - // subtract to avoid overflows, also use only half amplitude - output_l -= m_channels[ch].amplitude[ LEFT] * m_channels[ch].envelope[ LEFT] / 16 / 2; - output_r -= m_channels[ch].amplitude[RIGHT] * m_channels[ch].envelope[RIGHT] / 16 / 2; + // output is noise output + level = noise_out; } } // if the square wave is enabled - if (m_channels[ch].freq_enable) + else if (m_channels[ch].freq_enable) { - // if the channel level is high - if (m_channels[ch].level & 1) - { - output_l += m_channels[ch].amplitude[ LEFT] * m_channels[ch].envelope[ LEFT] / 16; - output_r += m_channels[ch].amplitude[RIGHT] * m_channels[ch].envelope[RIGHT] / 16; - } + // output is tone output + level = tone_out; + } + // if the output level is high + if (level > 0) + { + output_l += m_channels[ch].amplitude[ LEFT] * m_channels[ch].envelope[ LEFT] / 16 / level; + output_r += m_channels[ch].amplitude[RIGHT] * m_channels[ch].envelope[RIGHT] / 16 / level; } } @@ -298,19 +284,19 @@ void saa1099_device::sound_stream_update(sound_stream &stream, stream_sample_t * /* update the state of the noise generator * polynomial is x^18 + x^11 + x (i.e. 0x20400) and is a plain XOR, initial state is probably all 1s * see http://www.vogons.org/viewtopic.php?f=9&t=51695 */ - m_noise[ch].counter -= m_noise[ch].freq; - while (m_noise[ch].counter < 0) + while (m_noise[ch].counter <= 0) { - m_noise[ch].counter += m_sample_rate; + m_noise[ch].counter += m_noise[ch].freq; // clock / ((511 - frequency) * 2^(8 - octave)) or clock / 2^(8 + noise period) if( ((m_noise[ch].level & 0x20000) == 0) != ((m_noise[ch].level & 0x0400) == 0) ) m_noise[ch].level = (m_noise[ch].level << 1) | 1; else m_noise[ch].level <<= 1; } + m_noise[ch].counter -= clock_divider; } /* write sound data to the buffer */ - outputs[LEFT][j] = output_l / 6; - outputs[RIGHT][j] = output_r / 6; + stream.put_int(LEFT, j, output_l, 32768 * 6); + stream.put_int(RIGHT, j, output_r, 32768 * 6); } } @@ -332,7 +318,7 @@ void saa1099_device::envelope_w(int ch) m_channels[ch*3+0].envelope[ LEFT] = m_channels[ch*3+1].envelope[ LEFT] = m_channels[ch*3+2].envelope[ LEFT] = envelope[mode][step] & mask; - if (m_env_reverse_right[ch] & 0x01) + if (m_env_reverse_right[ch]) { m_channels[ch*3+0].envelope[RIGHT] = m_channels[ch*3+1].envelope[RIGHT] = @@ -407,21 +393,13 @@ void saa1099_device::data_w(u8 data) break; /* channel i frequency enable */ case 0x14: - m_channels[0].freq_enable = data & 0x01; - m_channels[1].freq_enable = data & 0x02; - m_channels[2].freq_enable = data & 0x04; - m_channels[3].freq_enable = data & 0x08; - m_channels[4].freq_enable = data & 0x10; - m_channels[5].freq_enable = data & 0x20; + for (ch = 0; ch < 6; ch++) + m_channels[ch].freq_enable = BIT(data, ch); break; /* channel i noise enable */ case 0x15: - m_channels[0].noise_enable = data & 0x01; - m_channels[1].noise_enable = data & 0x02; - m_channels[2].noise_enable = data & 0x04; - m_channels[3].noise_enable = data & 0x08; - m_channels[4].noise_enable = data & 0x10; - m_channels[5].noise_enable = data & 0x20; + for (ch = 0; ch < 6; ch++) + m_channels[ch].noise_enable = BIT(data, ch); break; /* noise generators parameters */ case 0x16: @@ -431,28 +409,26 @@ void saa1099_device::data_w(u8 data) /* envelope generators parameters */ case 0x18: case 0x19: ch = reg - 0x18; - m_env_reverse_right[ch] = data & 0x01; + m_env_reverse_right[ch] = BIT(data, 0); m_env_mode[ch] = (data >> 1) & 0x07; - m_env_bits[ch] = data & 0x10; - m_env_clock[ch] = data & 0x20; - m_env_enable[ch] = data & 0x80; + m_env_bits[ch] = BIT(data, 4); + m_env_clock[ch] = BIT(data, 5); + m_env_enable[ch] = BIT(data, 7); /* reset the envelope */ m_env_step[ch] = 0; break; /* channels enable & reset generators */ case 0x1c: - m_all_ch_enable = data & 0x01; - m_sync_state = data & 0x02; - if (data & 0x02) + m_all_ch_enable = BIT(data, 0); + m_sync_state = BIT(data, 1); + if (BIT(data, 1)) { - int i; - /* Synch & Reset generators */ logerror("%s: -reg 0x1c- Chip reset\n", machine().describe_context()); - for (i = 0; i < 6; i++) + for (int i = 0; i < 6; i++) { m_channels[i].level = 0; - m_channels[i].counter = 0.0; + m_channels[i].counter = m_channels[i].freq(); } } break; |