int BurnYM2612Init(int num, int nClockFrequency, FM_IRQHANDLER IRQCallback, int (*StreamCallback)(int), double (*GetTimeCallback)(), int bAddSignal)
{
if (num > MAX_YM2612) num = MAX_YM2612;
BurnTimerInit(&YM2612TimerOver, GetTimeCallback);
if (nBurnSoundRate <= 0) {
BurnYM2612StreamCallback = YM2612StreamCallbackDummy;
BurnYM2612Update = YM2612UpdateDummy;
YM2612Init(num, nClockFrequency, 11025, &BurnOPNTimerCallback, IRQCallback);
return 0;
}
BurnYM2612StreamCallback = StreamCallback;
nBurnYM2612SoundRate = nBurnSoundRate;
BurnYM2612Update = YM2612UpdateNormal;
YM2612Init(num, nClockFrequency, nBurnYM2612SoundRate, &BurnOPNTimerCallback, IRQCallback);
pBuffer = (short*)malloc(4096 * 2 * num * sizeof(short));
memset(pBuffer, 0, 4096 * 2 * num * sizeof(short));
nYM2612Position = 0;
nFractionalPosition = 0;
nNumChips = num;
bYM2612AddSignal = bAddSignal;
return 0;
}
void sound_init( void )
{
/* Initialize FM chip */
if ((system_hw & SYSTEM_PBC) == SYSTEM_MD)
{
/* YM2612 */
YM2612Init();
YM2612Config(config.dac_bits);
YM_Reset = YM2612ResetChip;
YM_Update = YM2612Update;
YM_Write = YM2612Write;
/* chip is running a VCLK / 144 = MCLK / 7 / 144 */
fm_cycles_ratio = 144 * 7;
}
else
{
/* YM2413 */
YM2413Init();
YM_Reset = YM2413ResetChip;
YM_Update = YM2413Update;
YM_Write = YM2413Write;
/* chip is running a ZCLK / 72 = MCLK / 15 / 72 */
fm_cycles_ratio = 72 * 15;
}
/* Initialize PSG chip */
SN76489_Config(0, config.psg_preamp, config.psgBoostNoise, 0xff);
}
int YM2612_sh_start(const struct MachineSound *msound)
{
int i,j;
int rate = Machine->sample_rate;
char buf[YM2612_NUMBUF][40];
const char *name[YM2612_NUMBUF];
intf = msound->sound_interface;
if( intf->num > MAX_2612 ) return 1;
/* FM init */
/* Timer Handler set */
FMTimerInit();
/* stream system initialize */
for (i = 0;i < intf->num;i++)
{
int vol[YM2612_NUMBUF];
/* stream setup */
for (j = 0 ; j < YM2612_NUMBUF ; j++)
{
vol[j] = intf->mixing_level[i];
name[j] = buf[j];
sprintf(buf[j],"YM2612(%s) #%d",j < 2 ? "FM" : "ADPCM",i);
}
stream[i] = stream_init_multi(YM2612_NUMBUF,
name,vol,rate,FM_OUTPUT_BIT,
i,YM2612UpdateOne);
}
/**** initialize YM2612 ****/
if (YM2612Init(intf->num,intf->baseclock,rate,TimerHandler,IRQHandler) == 0)
return 0;
/* error */
return 1;
}
static void *ym2612_start(int sndindex, int clock, const void *config)
{
static const struct YM2612interface dummy = { 0 };
int rate = Machine->sample_rate;
struct ym2612_info *info;
info = auto_malloc(sizeof(*info));
memset(info, 0, sizeof(*info));
info->intf = config ? config : &dummy;
/* FM init */
/* Timer Handler set */
info->timer[0] =timer_alloc_ptr(timer_callback_2612_0, info);
info->timer[1] =timer_alloc_ptr(timer_callback_2612_1, info);
/* stream system initialize */
info->stream = stream_create(0,2,rate,info,ym2612_stream_update);
/**** initialize YM2612 ****/
info->chip = YM2612Init(info,sndindex,clock,rate,TimerHandler,IRQHandler);
state_save_register_func_postload_ptr(ym2612_postload, info);
if (info->chip)
return info;
/* error */
return NULL;
}
/* Initialize sound chips emulation */
void sound_init(void)
{
/* Number of M-cycles executed per second. */
/* */
/* All emulated chips are kept in sync by using a common oscillator (MCLOCK) */
/* */
/* The original console would run exactly 53693175 M-cycles (53203424 for PAL), with */
/* 3420 M-cycles per line and 262 (313 for PAL) lines per frame, which gives an exact */
/* framerate of 59.92 (49.70 for PAL) fps. */
/* */
/* Since audio samples are generated at the end of the frame, to prevent audio skipping */
/* or lag between emulated frames, number of samples rendered per frame must be set to */
/* output samplerate (number of samples played per second) divided by output framerate */
/* (number of frames emulated per seconds). */
/* */
/* On some systems, we may want to achieve 100% smooth video rendering by synchronizing */
/* frame emulation with VSYNC, which frequency is generally not exactly those values. */
/* In that case, number of frames emulated per seconds is the same as the number of */
/* frames rendered per seconds by the host system video hardware. */
/* */
/* When no framerate is specified, base clock is original master clock value. */
/* Otherwise, it is based on the output framerate. */
/* */
double mclk = snd.frame_rate ? (MCYCLES_PER_LINE * lines_per_frame * snd.frame_rate) : system_clock;
/* For maximal accuracy, sound chips run in synchronization with 68k and Z80 cpus */
/* These values give the exact number of M-cycles executed per internal sample clock: */
/* . PSG chip runs at original rate and audio is resampled internally after each update */
/* . FM chips run by default (if HQ mode disabled) at the output rate directly */
/* We use 21.11 fixed point precision (max. mcycle value is 3420*313 i.e 21 bits max) */
psg_cycles_ratio = 16 * 15 * (1 << 11);
fm_cycles_ratio = (unsigned int)(mclk / (double) snd.sample_rate * 2048.0);
psg_cycles_count = 0;
fm_cycles_count = 0;
/* Initialize PSG core (input clock should be based on emulated system clock) */
SN76489_Init(mclk/15.0,snd.sample_rate);
/* Initialize FM cores (input clock and samplerate are only used when HQ mode is disabled) */
if ((system_hw & SYSTEM_PBC) == SYSTEM_MD)
{
/* YM2612 */
YM2612Init(mclk/7.0,snd.sample_rate);
YM_Reset = YM2612ResetChip;
YM_Update = YM2612Update;
YM_Write = YM2612Write;
/* In HQ mode, YM2612 is running at original rate (one sample each 144*7 M-cycles) */
/* Audio is resampled externally at the end of a frame. */
if (config.hq_fm)
{
fm_cycles_ratio = 144 * 7 * (1 << 11);
Fir_Resampler_time_ratio(mclk / (double)snd.sample_rate / (144.0 * 7.0), config.rolloff);
}
}
else
{
/* YM2413 */
YM2413Init(mclk/15.0,snd.sample_rate);
YM_Reset = YM2413ResetChip;
YM_Update = YM2413Update;
YM_Write = YM2413Write;
/* In HQ mode, YM2413 is running at original rate (one sample each 72*15 M-cycles) */
/* Audio is resampled externally at the end of a frame. */
if (config.hq_fm)
{
fm_cycles_ratio = 72 * 15 * (1 << 11);
Fir_Resampler_time_ratio(mclk / (double)snd.sample_rate / (72.0 * 15.0), config.rolloff);
}
}
#ifdef LOGSOUND
error("%f mcycles per second\n", mclk);
error("%d mcycles per PSG sample\n", psg_cycles_ratio);
error("%d mcycles per FM sample\n", fm_cycles_ratio);
#endif
}
