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Diffstat (limited to 'src/emu/sound/ymz280b.c')
-rw-r--r-- | src/emu/sound/ymz280b.c | 1125 |
1 files changed, 1125 insertions, 0 deletions
diff --git a/src/emu/sound/ymz280b.c b/src/emu/sound/ymz280b.c new file mode 100644 index 00000000000..e9df9742413 --- /dev/null +++ b/src/emu/sound/ymz280b.c @@ -0,0 +1,1125 @@ +/* + + Yamaha YMZ280B driver + by Aaron Giles + + YMZ280B 8-Channel PCMD8 PCM/ADPCM Decoder + + Features as listed in LSI-4MZ280B3 data sheet: + Voice data stored in external memory can be played back simultaneously for up to eight voices + Voice data format can be selected from 4-bit ADPCM, 8-bit PCM and 16-bit PCM + Control of voice data external memory + Up to 16M bytes of ROM or SRAM (x 8 bits, access time 150ms max) can be connected + Continuous access is possible + Loop playback between selective addresses is possible + Voice data playback frequency control + 4-bit ADPCM ................ 0.172 to 44.1kHz in 256 steps + 8-bit PCM, 16-bit PCM ...... 0.172 to 88.2kHz in 512 steps + 256 steps total level and 16 steps panpot can be set + Voice signal is output in stereo 16-bit 2's complement MSB-first format + +*/ + + +#include <math.h> + +#include "sndintrf.h" +#include "streams.h" +#include "ymz280b.h" + + +#define MAX_SAMPLE_CHUNK 10000 +#define MAKE_WAVS 0 + +#define FRAC_BITS 14 +#define FRAC_ONE (1 << FRAC_BITS) +#define FRAC_MASK (FRAC_ONE - 1) + +#define INTERNAL_BUFFER_SIZE (1 << 15) +#define INTERNAL_SAMPLE_RATE (chip->master_clock * 2.0) + +#if MAKE_WAVS +#include "wavwrite.h" +#endif + + +/* struct describing a single playing ADPCM voice */ +struct YMZ280BVoice +{ + UINT8 playing; /* 1 if we are actively playing */ + + UINT8 keyon; /* 1 if the key is on */ + UINT8 looping; /* 1 if looping is enabled */ + UINT8 mode; /* current playback mode */ + UINT16 fnum; /* frequency */ + UINT8 level; /* output level */ + UINT8 pan; /* panning */ + + UINT32 start; /* start address, in nibbles */ + UINT32 stop; /* stop address, in nibbles */ + UINT32 loop_start; /* loop start address, in nibbles */ + UINT32 loop_end; /* loop end address, in nibbles */ + UINT32 position; /* current position, in nibbles */ + + INT32 signal; /* current ADPCM signal */ + INT32 step; /* current ADPCM step */ + + INT32 loop_signal; /* signal at loop start */ + INT32 loop_step; /* step at loop start */ + UINT32 loop_count; /* number of loops so far */ + + INT32 output_left; /* output volume (left) */ + INT32 output_right; /* output volume (right) */ + INT32 output_step; /* step value for frequency conversion */ + INT32 output_pos; /* current fractional position */ + INT16 last_sample; /* last sample output */ + INT16 curr_sample; /* current sample target */ + UINT8 irq_schedule; /* 1 if the IRQ state is updated by timer */ +}; + +struct YMZ280BChip +{ + sound_stream * stream; /* which stream are we using */ + UINT8 *region_base; /* pointer to the base of the region */ + UINT8 current_register; /* currently accessible register */ + UINT8 status_register; /* current status register */ + UINT8 irq_state; /* current IRQ state */ + UINT8 irq_mask; /* current IRQ mask */ + UINT8 irq_enable; /* current IRQ enable */ + UINT8 keyon_enable; /* key on enable */ + double master_clock; /* master clock frequency */ + void (*irq_callback)(int); /* IRQ callback */ + struct YMZ280BVoice voice[8]; /* the 8 voices */ + UINT32 rom_readback_addr; /* where the CPU can read the ROM */ + read8_handler ext_ram_read; /* external RAM read handler */ + write8_handler ext_ram_write; /* external RAM write handler */ + +#if MAKE_WAVS + void * wavresample; /* resampled waveform */ +#endif + + INT16 *scratch; +}; + +/* step size index shift table */ +static const int index_scale[8] = { 0x0e6, 0x0e6, 0x0e6, 0x0e6, 0x133, 0x199, 0x200, 0x266 }; + +/* lookup table for the precomputed difference */ +static int diff_lookup[16]; + +/* timer callback */ +static TIMER_CALLBACK_PTR( update_irq_state_timer_0 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_1 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_2 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_3 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_4 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_5 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_6 ); +static TIMER_CALLBACK_PTR( update_irq_state_timer_7 ); + +static void (*update_irq_state_cb[])(running_machine *, void *) = +{ + update_irq_state_timer_0, + update_irq_state_timer_1, + update_irq_state_timer_2, + update_irq_state_timer_3, + update_irq_state_timer_4, + update_irq_state_timer_5, + update_irq_state_timer_6, + update_irq_state_timer_7 +}; + + + +INLINE void update_irq_state(struct YMZ280BChip *chip) +{ + int irq_bits = chip->status_register & chip->irq_mask; + + /* always off if the enable is off */ + if (!chip->irq_enable) + irq_bits = 0; + + /* update the state if changed */ + if (irq_bits && !chip->irq_state) + { + chip->irq_state = 1; + if (chip->irq_callback) + (*chip->irq_callback)(1); + else logerror("YMZ280B: IRQ generated, but no callback specified!"); + } + else if (!irq_bits && chip->irq_state) + { + chip->irq_state = 0; + if (chip->irq_callback) + (*chip->irq_callback)(0); + else logerror("YMZ280B: IRQ generated, but no callback specified!"); + } +} + + +INLINE void update_step(struct YMZ280BChip *chip, struct YMZ280BVoice *voice) +{ + double frequency; + + /* compute the frequency */ + if (voice->mode == 1) + frequency = chip->master_clock * (double)((voice->fnum & 0x0ff) + 1) * (1.0 / 256.0); + else + frequency = chip->master_clock * (double)((voice->fnum & 0x1ff) + 1) * (1.0 / 256.0); + voice->output_step = (UINT32)(frequency * (double)FRAC_ONE / INTERNAL_SAMPLE_RATE); +} + + +INLINE void update_volumes(struct YMZ280BVoice *voice) +{ + if (voice->pan == 8) + { + voice->output_left = voice->level; + voice->output_right = voice->level; + } + else if (voice->pan < 8) + { + voice->output_left = voice->level; + voice->output_right = voice->level * voice->pan / 8; + } + else + { + voice->output_left = voice->level * (15 - voice->pan) / 8; + voice->output_right = voice->level; + } +} + + +static void YMZ280B_state_save_update_step(void *param) +{ + struct YMZ280BChip *chip = param; + int j; + for (j = 0; j < 8; j++) + { + struct YMZ280BVoice *voice = &chip->voice[j]; + update_step(chip, voice); + if(voice->irq_schedule) + timer_set_ptr(attotime_zero, chip, update_irq_state_cb[j]); + } +} + + +static void update_irq_state_timer_common(void *param, int voicenum) +{ + struct YMZ280BChip *chip = param; + struct YMZ280BVoice *voice = &chip->voice[voicenum]; + + if(!voice->irq_schedule) return; + + voice->playing = 0; + chip->status_register |= 1 << voicenum; + update_irq_state(chip); + voice->irq_schedule = 0; +} + +static TIMER_CALLBACK_PTR( update_irq_state_timer_0 ) { update_irq_state_timer_common(param, 0); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_1 ) { update_irq_state_timer_common(param, 1); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_2 ) { update_irq_state_timer_common(param, 2); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_3 ) { update_irq_state_timer_common(param, 3); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_4 ) { update_irq_state_timer_common(param, 4); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_5 ) { update_irq_state_timer_common(param, 5); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_6 ) { update_irq_state_timer_common(param, 6); } +static TIMER_CALLBACK_PTR( update_irq_state_timer_7 ) { update_irq_state_timer_common(param, 7); } + + +/********************************************************************************************** + + compute_tables -- compute the difference tables + +***********************************************************************************************/ + +static void compute_tables(void) +{ + int nib; + + /* loop over all nibbles and compute the difference */ + for (nib = 0; nib < 16; nib++) + { + int value = (nib & 0x07) * 2 + 1; + diff_lookup[nib] = (nib & 0x08) ? -value : value; + } +} + + + +/********************************************************************************************** + + generate_adpcm -- general ADPCM decoding routine + +***********************************************************************************************/ + +static int generate_adpcm(struct YMZ280BVoice *voice, UINT8 *base, INT16 *buffer, int samples) +{ + int position = voice->position; + int signal = voice->signal; + int step = voice->step; + int val; + + /* two cases: first cases is non-looping */ + if (!voice->looping) + { + /* loop while we still have samples to generate */ + while (samples) + { + /* compute the new amplitude and update the current step */ + val = base[position / 2] >> ((~position & 1) << 2); + signal += (step * diff_lookup[val & 15]) / 8; + + /* clamp to the maximum */ + if (signal > 32767) + signal = 32767; + else if (signal < -32768) + signal = -32768; + + /* adjust the step size and clamp */ + step = (step * index_scale[val & 7]) >> 8; + if (step > 0x6000) + step = 0x6000; + else if (step < 0x7f) + step = 0x7f; + + /* output to the buffer, scaling by the volume */ + *buffer++ = signal; + samples--; + + /* next! */ + position++; + if (position >= voice->stop) + break; + } + } + + /* second case: looping */ + else + { + /* loop while we still have samples to generate */ + while (samples) + { + /* compute the new amplitude and update the current step */ + val = base[position / 2] >> ((~position & 1) << 2); + signal += (step * diff_lookup[val & 15]) / 8; + + /* clamp to the maximum */ + if (signal > 32767) + signal = 32767; + else if (signal < -32768) + signal = -32768; + + /* adjust the step size and clamp */ + step = (step * index_scale[val & 7]) >> 8; + if (step > 0x6000) + step = 0x6000; + else if (step < 0x7f) + step = 0x7f; + + /* output to the buffer, scaling by the volume */ + *buffer++ = signal; + samples--; + + /* next! */ + position++; + if (position == voice->loop_start && voice->loop_count == 0) + { + voice->loop_signal = signal; + voice->loop_step = step; + } + if (position >= voice->loop_end) + { + if (voice->keyon) + { + position = voice->loop_start; + signal = voice->loop_signal; + step = voice->loop_step; + voice->loop_count++; + } + } + if (position >= voice->stop) + break; + } + } + + /* update the parameters */ + voice->position = position; + voice->signal = signal; + voice->step = step; + + return samples; +} + + + +/********************************************************************************************** + + generate_pcm8 -- general 8-bit PCM decoding routine + +***********************************************************************************************/ + +static int generate_pcm8(struct YMZ280BVoice *voice, UINT8 *base, INT16 *buffer, int samples) +{ + int position = voice->position; + int val; + + /* two cases: first cases is non-looping */ + if (!voice->looping) + { + /* loop while we still have samples to generate */ + while (samples) + { + /* fetch the current value */ + val = base[position / 2]; + + /* output to the buffer, scaling by the volume */ + *buffer++ = (INT8)val * 256; + samples--; + + /* next! */ + position += 2; + if (position >= voice->stop) + break; + } + } + + /* second case: looping */ + else + { + /* loop while we still have samples to generate */ + while (samples) + { + /* fetch the current value */ + val = base[position / 2]; + + /* output to the buffer, scaling by the volume */ + *buffer++ = (INT8)val * 256; + samples--; + + /* next! */ + position += 2; + if (position >= voice->loop_end) + { + if (voice->keyon) + position = voice->loop_start; + } + if (position >= voice->stop) + break; + } + } + + /* update the parameters */ + voice->position = position; + + return samples; +} + + + +/********************************************************************************************** + + generate_pcm16 -- general 16-bit PCM decoding routine + +***********************************************************************************************/ + +static int generate_pcm16(struct YMZ280BVoice *voice, UINT8 *base, INT16 *buffer, int samples) +{ + int position = voice->position; + int val; + + /* two cases: first cases is non-looping */ + if (!voice->looping) + { + /* loop while we still have samples to generate */ + while (samples) + { + /* fetch the current value */ + val = (INT16)((base[position / 2 + 1] << 8) + base[position / 2]); + + /* output to the buffer, scaling by the volume */ + *buffer++ = val; + samples--; + + /* next! */ + position += 4; + if (position >= voice->stop) + break; + } + } + + /* second case: looping */ + else + { + /* loop while we still have samples to generate */ + while (samples) + { + /* fetch the current value */ + val = (INT16)((base[position / 2 + 1] << 8) + base[position / 2]); + + /* output to the buffer, scaling by the volume */ + *buffer++ = val; + samples--; + + /* next! */ + position += 4; + if (position >= voice->loop_end) + { + if (voice->keyon) + position = voice->loop_start; + } + if (position >= voice->stop) + break; + } + } + + /* update the parameters */ + voice->position = position; + + return samples; +} + + + +/********************************************************************************************** + + ymz280b_update -- update the sound chip so that it is in sync with CPU execution + +***********************************************************************************************/ + +static void ymz280b_update(void *param, stream_sample_t **inputs, stream_sample_t **buffer, int length) +{ + struct YMZ280BChip *chip = param; + stream_sample_t *lacc = buffer[0]; + stream_sample_t *racc = buffer[1]; + int v; + + /* clear out the accumulator */ + memset(lacc, 0, length * sizeof(lacc[0])); + memset(racc, 0, length * sizeof(racc[0])); + + /* loop over voices */ + for (v = 0; v < 8; v++) + { + struct YMZ280BVoice *voice = &chip->voice[v]; + INT16 prev = voice->last_sample; + INT16 curr = voice->curr_sample; + INT16 *curr_data = chip->scratch; + INT32 *ldest = lacc; + INT32 *rdest = racc; + UINT32 new_samples, samples_left; + UINT32 final_pos; + int remaining = length; + int lvol = voice->output_left; + int rvol = voice->output_right; + + /* quick out if we're not playing and we're at 0 */ + if (!voice->playing && curr == 0) + continue; + + /* finish off the current sample */ +// if (voice->output_pos > 0) + { + /* interpolate */ + while (remaining > 0 && voice->output_pos < FRAC_ONE) + { + int interp_sample = (((INT32)prev * (FRAC_ONE - voice->output_pos)) + ((INT32)curr * voice->output_pos)) >> FRAC_BITS; + *ldest++ += interp_sample * lvol; + *rdest++ += interp_sample * rvol; + voice->output_pos += voice->output_step; + remaining--; + } + + /* if we're over, continue; otherwise, we're done */ + if (voice->output_pos >= FRAC_ONE) + voice->output_pos -= FRAC_ONE; + else + continue; + } + + /* compute how many new samples we need */ + final_pos = voice->output_pos + remaining * voice->output_step; + new_samples = (final_pos + FRAC_ONE) >> FRAC_BITS; + if (new_samples > MAX_SAMPLE_CHUNK) + new_samples = MAX_SAMPLE_CHUNK; + samples_left = new_samples; + + /* generate them into our buffer */ + if (voice->playing) + { + switch (voice->mode) + { + case 1: samples_left = generate_adpcm(voice, chip->region_base, chip->scratch, new_samples); break; + case 2: samples_left = generate_pcm8(voice, chip->region_base, chip->scratch, new_samples); break; + case 3: samples_left = generate_pcm16(voice, chip->region_base, chip->scratch, new_samples); break; + default: + case 0: samples_left = 0; memset(chip->scratch, 0, new_samples * sizeof(chip->scratch[0])); break; + } + } + + /* if there are leftovers, ramp back to 0 */ + if (samples_left) + { + int base = new_samples - samples_left; + int i, t = (base == 0) ? curr : chip->scratch[base - 1]; + for (i = 0; i < samples_left; i++) + { + if (t < 0) t = -((-t * 15) >> 4); + else if (t > 0) t = (t * 15) >> 4; + chip->scratch[base + i] = t; + } + + /* if we hit the end and IRQs are enabled, signal it */ + if (base != 0) + { + voice->playing = 0; + + /* set update_irq_state_timer. IRQ is signaled on next CPU execution. */ + timer_set_ptr(attotime_zero, chip, update_irq_state_cb[v]); + voice->irq_schedule = 1; + } + } + + /* advance forward one sample */ + prev = curr; + curr = *curr_data++; + + /* then sample-rate convert with linear interpolation */ + while (remaining > 0) + { + /* interpolate */ + while (remaining > 0 && voice->output_pos < FRAC_ONE) + { + int interp_sample = (((INT32)prev * (FRAC_ONE - voice->output_pos)) + ((INT32)curr * voice->output_pos)) >> FRAC_BITS; + *ldest++ += interp_sample * lvol; + *rdest++ += interp_sample * rvol; + voice->output_pos += voice->output_step; + remaining--; + } + + /* if we're over, grab the next samples */ + if (voice->output_pos >= FRAC_ONE) + { + voice->output_pos -= FRAC_ONE; + prev = curr; + curr = *curr_data++; + } + } + + /* remember the last samples */ + voice->last_sample = prev; + voice->curr_sample = curr; + } + + for (v = 0; v < length; v++) + { + buffer[0][v] /= 256; + buffer[1][v] /= 256; + } +} + + + +/********************************************************************************************** + + YMZ280B_sh_start -- start emulation of the YMZ280B + +***********************************************************************************************/ + +static void *ymz280b_start(int sndindex, int clock, const void *config) +{ + const struct YMZ280Binterface *intf = config; + struct YMZ280BChip *chip; + + chip = auto_malloc(sizeof(*chip)); + memset(chip, 0, sizeof(*chip)); + + chip->ext_ram_read = intf->ext_read; + chip->ext_ram_write = intf->ext_write; + + /* compute ADPCM tables */ + compute_tables(); + + /* initialize the rest of the structure */ + chip->master_clock = (double)clock / 384.0; + chip->region_base = memory_region(intf->region); + chip->irq_callback = intf->irq_callback; + + /* create the stream */ + chip->stream = stream_create(0, 2, INTERNAL_SAMPLE_RATE, chip, ymz280b_update); + + /* allocate memory */ + chip->scratch = auto_malloc(sizeof(chip->scratch[0]) * MAX_SAMPLE_CHUNK); + + /* state save */ + { + int j; + state_save_register_item("YMZ280B", sndindex, chip->current_register); + state_save_register_item("YMZ280B", sndindex, chip->status_register); + state_save_register_item("YMZ280B", sndindex, chip->irq_state); + state_save_register_item("YMZ280B", sndindex, chip->irq_mask); + state_save_register_item("YMZ280B", sndindex, chip->irq_enable); + state_save_register_item("YMZ280B", sndindex, chip->keyon_enable); + state_save_register_item("YMZ280B", sndindex, chip->rom_readback_addr); + for (j = 0; j < 8; j++) + { + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].playing); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].keyon); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].looping); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].mode); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].fnum); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].level); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].pan); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].start); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].stop); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].loop_start); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].loop_end); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].position); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].signal); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].step); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].loop_signal); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].loop_step); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].loop_count); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].output_left); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].output_right); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].output_pos); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].last_sample); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].curr_sample); + state_save_register_item("YMZ280B.voice", sndindex*8+j, chip->voice[j].irq_schedule); + } + } + + state_save_register_func_postload_ptr(YMZ280B_state_save_update_step, chip); + +#if MAKE_WAVS + chip->wavresample = wav_open("resamp.wav", INTERNAL_SAMPLE_RATE, 2); +#endif + + /* success */ + return chip; +} + + + +/********************************************************************************************** + + YMZ280B_sh_stop -- stop emulation of the YMZ280B + +***********************************************************************************************/ + +void YMZ280B_sh_stop(void) +{ +#if MAKE_WAVS +{ + int i; + + for (i = 0; i < MAX_BSMT2000; i++) + { + if (ymz280b[i].wavresample) + wav_close(ymz280b[i].wavresample); + } +} +#endif +} + + + +/********************************************************************************************** + + write_to_register -- handle a write to the current register + +***********************************************************************************************/ + +static void write_to_register(struct YMZ280BChip *chip, int data) +{ + struct YMZ280BVoice *voice; + int i; + + /* force an update */ + stream_update(chip->stream); + + /* lower registers follow a pattern */ + if (chip->current_register < 0x80) + { + voice = &chip->voice[(chip->current_register >> 2) & 7]; + + switch (chip->current_register & 0xe3) + { + case 0x00: /* pitch low 8 bits */ + voice->fnum = (voice->fnum & 0x100) | (data & 0xff); + update_step(chip, voice); + break; + + case 0x01: /* pitch upper 1 bit, loop, key on, mode */ + voice->fnum = (voice->fnum & 0xff) | ((data & 0x01) << 8); + voice->looping = (data & 0x10) >> 4; + voice->mode = (data & 0x60) >> 5; + if (!voice->keyon && (data & 0x80) && chip->keyon_enable) + { + voice->playing = 1; + voice->position = voice->start; + voice->signal = voice->loop_signal = 0; + voice->step = voice->loop_step = 0x7f; + voice->loop_count = 0; + + /* if update_irq_state_timer is set, cancel it. */ + voice->irq_schedule = 0; + } + if (voice->keyon && !(data & 0x80) && !voice->looping) + { + voice->playing = 0; + + /* if update_irq_state_timer is set, cancel it. */ + voice->irq_schedule = 0; + } + voice->keyon = (data & 0x80) >> 7; + update_step(chip, voice); + break; + + case 0x02: /* total level */ + voice->level = data; + update_volumes(voice); + break; + + case 0x03: /* pan */ + voice->pan = data & 0x0f; + update_volumes(voice); + break; + + case 0x20: /* start address high */ + voice->start = (voice->start & (0x00ffff << 1)) | (data << 17); + break; + + case 0x21: /* loop start address high */ + voice->loop_start = (voice->loop_start & (0x00ffff << 1)) | (data << 17); + break; + + case 0x22: /* loop end address high */ + voice->loop_end = (voice->loop_end & (0x00ffff << 1)) | (data << 17); + break; + + case 0x23: /* stop address high */ + voice->stop = (voice->stop & (0x00ffff << 1)) | (data << 17); + break; + + case 0x40: /* start address middle */ + voice->start = (voice->start & (0xff00ff << 1)) | (data << 9); + break; + + case 0x41: /* loop start address middle */ + voice->loop_start = (voice->loop_start & (0xff00ff << 1)) | (data << 9); + break; + + case 0x42: /* loop end address middle */ + voice->loop_end = (voice->loop_end & (0xff00ff << 1)) | (data << 9); + break; + + case 0x43: /* stop address middle */ + voice->stop = (voice->stop & (0xff00ff << 1)) | (data << 9); + break; + + case 0x60: /* start address low */ + voice->start = (voice->start & (0xffff00 << 1)) | (data << 1); + break; + + case 0x61: /* loop start address low */ + voice->loop_start = (voice->loop_start & (0xffff00 << 1)) | (data << 1); + break; + + case 0x62: /* loop end address low */ + voice->loop_end = (voice->loop_end & (0xffff00 << 1)) | (data << 1); + break; + + case 0x63: /* stop address low */ + voice->stop = (voice->stop & (0xffff00 << 1)) | (data << 1); + break; + + default: + logerror("YMZ280B: unknown register write %02X = %02X\n", chip->current_register, data); + break; + } + } + + /* upper registers are special */ + else + { + switch (chip->current_register) + { + case 0x84: /* ROM readback / RAM write (high) */ + chip->rom_readback_addr &= 0xffff; + chip->rom_readback_addr |= (data<<16); + break; + + case 0x85: /* ROM readback / RAM write (med) */ + chip->rom_readback_addr &= 0xff00ff; + chip->rom_readback_addr |= (data<<8); + break; + + case 0x86: /* ROM readback / RAM write (low) */ + chip->rom_readback_addr &= 0xffff00; + chip->rom_readback_addr |= data; + break; + + case 0x87: /* RAM write */ + if (chip->ext_ram_write) + chip->ext_ram_write(chip->rom_readback_addr, data); + else + logerror("YMZ280B attempted RAM write to %X\n", chip->rom_readback_addr); + break; + + case 0xfe: /* IRQ mask */ + chip->irq_mask = data; + update_irq_state(chip); + break; + + case 0xff: /* IRQ enable, test, etc */ + chip->irq_enable = (data & 0x10) >> 4; + update_irq_state(chip); + + if (chip->keyon_enable && !(data & 0x80)) + { + for (i = 0; i < 8; i++) + { + chip->voice[i].playing = 0; + + /* if update_irq_state_timer is set, cancel it. */ + chip->voice[i].irq_schedule = 0; + } + } + else if (!chip->keyon_enable && (data & 0x80)) + { + for (i = 0; i < 8; i++) + { + if (chip->voice[i].keyon && chip->voice[i].looping) + chip->voice[i].playing = 1; + } + } + chip->keyon_enable = (data & 0x80) >> 7; + break; + + default: + logerror("YMZ280B: unknown register write %02X = %02X\n", chip->current_register, data); + break; + } + } +} + + + +/********************************************************************************************** + + compute_status -- determine the status bits + +***********************************************************************************************/ + +static int compute_status(struct YMZ280BChip *chip) +{ + UINT8 result; + + /* ROM/RAM readback? */ + if (chip->current_register == 0x86) + { + return chip->region_base[chip->rom_readback_addr]; + } + + /* force an update */ + stream_update(chip->stream); + + result = chip->status_register; + + /* clear the IRQ state */ + chip->status_register = 0; + update_irq_state(chip); + + return result; +} + + + +/********************************************************************************************** + + YMZ280B_status_0_r/YMZ280B_status_1_r -- handle a read from the status register + +***********************************************************************************************/ + +READ8_HANDLER( YMZ280B_status_0_r ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + return compute_status(chip); +} + +READ8_HANDLER( YMZ280B_status_1_r ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + return compute_status(chip); +} + +READ16_HANDLER( YMZ280B_status_0_lsb_r ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + return compute_status(chip); +} + +READ16_HANDLER( YMZ280B_status_0_msb_r ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + return compute_status(chip) << 8; +} + +READ16_HANDLER( YMZ280B_status_1_lsb_r ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + return compute_status(chip); +} + +READ16_HANDLER( YMZ280B_status_1_msb_r ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + return compute_status(chip) << 8; +} + +/********************************************************************************************** + + YMZ280B_register_0_w/YMZ280B_register_1_w -- handle a write to the register select + +***********************************************************************************************/ + +WRITE8_HANDLER( YMZ280B_register_0_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + chip->current_register = data; +} + +WRITE8_HANDLER( YMZ280B_register_1_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + chip->current_register = data; +} + +WRITE16_HANDLER( YMZ280B_register_0_lsb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + if (ACCESSING_LSB) chip->current_register = data & 0xff; +} + +WRITE16_HANDLER( YMZ280B_register_0_msb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + if (ACCESSING_MSB) chip->current_register = (data >> 8) & 0xff; +} + +WRITE16_HANDLER( YMZ280B_register_1_lsb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + if (ACCESSING_LSB) chip->current_register = data & 0xff; +} + +WRITE16_HANDLER( YMZ280B_register_1_msb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + if (ACCESSING_MSB) chip->current_register = (data >> 8) & 0xff; +} + +/********************************************************************************************** + + YMZ280B_data_0_w/YMZ280B_data_1_w -- handle a write to the current register + +***********************************************************************************************/ + +WRITE8_HANDLER( YMZ280B_data_0_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + write_to_register(chip, data); +} + +WRITE8_HANDLER( YMZ280B_data_1_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + write_to_register(chip, data); +} + +WRITE16_HANDLER( YMZ280B_data_0_lsb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + if (ACCESSING_LSB) write_to_register(chip, data & 0xff); +} + +WRITE16_HANDLER( YMZ280B_data_0_msb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + if (ACCESSING_MSB) write_to_register(chip, (data >> 8) & 0xff); +} + +WRITE16_HANDLER( YMZ280B_data_1_lsb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + if (ACCESSING_LSB) write_to_register(chip, data & 0xff); +} + +WRITE16_HANDLER( YMZ280B_data_1_msb_w ) +{ + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + if (ACCESSING_MSB) write_to_register(chip, (data >> 8) & 0xff); +} + +/********************************************************************************************** + + YMZ280B_data_0_r/YMZ280B_data_1_r -- handle an external RAM read + +***********************************************************************************************/ + +READ8_HANDLER( YMZ280B_data_0_r ) +{ + UINT8 data; + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 0); + data = chip->ext_ram_read(chip->rom_readback_addr - 1); + chip->rom_readback_addr++; + return data; +} + +READ8_HANDLER( YMZ280B_data_1_r ) +{ + UINT8 data; + struct YMZ280BChip *chip = sndti_token(SOUND_YMZ280B, 1); + data = chip->ext_ram_read(chip->rom_readback_addr - 1); + chip->rom_readback_addr++; + return data; +} + + + + +/************************************************************************** + * Generic get_info + **************************************************************************/ + +static void ymz280b_set_info(void *token, UINT32 state, sndinfo *info) +{ + switch (state) + { + /* no parameters to set */ + } +} + + +void ymz280b_get_info(void *token, UINT32 state, sndinfo *info) +{ + switch (state) + { + /* --- the following bits of info are returned as 64-bit signed integers --- */ + + /* --- the following bits of info are returned as pointers to data or functions --- */ + case SNDINFO_PTR_SET_INFO: info->set_info = ymz280b_set_info; break; + case SNDINFO_PTR_START: info->start = ymz280b_start; break; + case SNDINFO_PTR_STOP: /* Nothing */ break; + case SNDINFO_PTR_RESET: /* Nothing */ break; + + /* --- the following bits of info are returned as NULL-terminated strings --- */ + case SNDINFO_STR_NAME: info->s = "YMZ280B"; break; + case SNDINFO_STR_CORE_FAMILY: info->s = "Yamaha Wavetable"; break; + case SNDINFO_STR_CORE_VERSION: info->s = "1.0"; break; + case SNDINFO_STR_CORE_FILE: info->s = __FILE__; break; + case SNDINFO_STR_CORE_CREDITS: info->s = "Copyright (c) 2004, The MAME Team"; break; + } +} + |