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Fix AY-3-8910/YM2149 and derivatives envelope handling.

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This commit is contained in:
Couriersud 2008-04-26 18:57:15 +00:00
parent 8d1c77366c
commit 899c47f7b8
1 changed files with 12 additions and 12 deletions
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24
src/emu/sound/ay8910.c
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@ -218,7 +218,7 @@ static ay_ym_param ay8910_param =
static void AY8910_write_reg(struct AY8910 *PSG, int r, int v)
{
//if (r != 4 && r !=5) printf("%d %x %02x\n", PSG->index, r, v);
//if (r >= 11 && r <= 13 ) printf("%d %x %02x\n", PSG->index, r, v);
PSG->regs[r] = v;
/* A note about the period of tones, noise and envelope: for speed reasons,*/
@ -386,7 +386,7 @@ static void AY8910_update(void *param,stream_sample_t **inputs, stream_sample_t
for (chan = 0; chan < NUM_CHANNELS; chan++)
{
PSG->Count[chan]++;
if (PSG->Count[chan] >= TONE_PERIOD(PSG, chan) * PSG->step)
if (PSG->Count[chan] >= TONE_PERIOD(PSG, chan))
{
PSG->Output[chan] ^= 1;
PSG->Count[chan] = 0;;
@ -394,7 +394,7 @@ static void AY8910_update(void *param,stream_sample_t **inputs, stream_sample_t
}
PSG->CountN++;
if (PSG->CountN >= NOISE_PERIOD(PSG) * PSG->step)
if (PSG->CountN >= NOISE_PERIOD(PSG))
{
/* Is noise output going to change? */
if ((PSG->RNG + 1) & 2) /* (bit0^bit1)? */
@ -426,7 +426,7 @@ static void AY8910_update(void *param,stream_sample_t **inputs, stream_sample_t
if (PSG->Holding == 0)
{
PSG->CountE++;
if (PSG->CountE >= ENVELOPE_PERIOD(PSG))
if (PSG->CountE >= ENVELOPE_PERIOD(PSG) * PSG->step )
{
PSG->CountE = 0;
PSG->CountEnv--;
@ -653,10 +653,11 @@ void *ay8910_start_ym(sound_type chip_type, int sndindex, int clock, const struc
{
case SOUND_AY8910:
case SOUND_AY8930:
info->step = 1;
info->step = 2;
info->par = &ay8910_param;
info->parE = &ay8910_param;
info->zero_is_off = 1;
info->EnvP = 0x0F;
break;
case SOUND_YM2149:
case SOUND_YM2203:
@ -667,20 +668,19 @@ void *ay8910_start_ym(sound_type chip_type, int sndindex, int clock, const struc
case SOUND_YMZ294:
case SOUND_YM3439:
default:
info->step = 2;
info->step = 1;
info->par = &ym2149_param;
info->parE = &ym2149_paramE;
info->zero_is_off = 0;
info->EnvP = 0x1F;
break;
}
info->EnvP = info->step * 16 - 1;
build_mixer_table(info);
/* the step clock for the tone and noise generators is the chip clock */
/* divided by 8 for the YM2149 and 16 for the AY-3-8910, To emulate a */
/* full cycle, we have to use a divisor of 4 resp. 8 */
info->Channel = stream_create(0,info->streams,clock / (8 / info->step),info,AY8910_update);
/* The envelope is pacing twice as fast for the YM2149 as for the AY-3-8910, */
/* This handled by the step parameter. Consequently we use a divider of 8 here. */
info->Channel = stream_create(0,info->streams,clock / 8 ,info,AY8910_update);
ay8910_set_clock_ym(info,clock);
AY8910_statesave(info, sndindex);
@ -717,7 +717,7 @@ void ay8910_reset_ym(void *chip)
void ay8910_set_clock_ym(void *chip, int clock)
{
struct AY8910 *PSG = chip;
stream_set_sample_rate(PSG->Channel, clock / (8 / PSG->step));
stream_set_sample_rate(PSG->Channel, clock / 8 );
}
void ay8910_write_ym(void *chip, int addr, int data)