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YM2612: fix LFO AM waveform [Eke-Eke, R. Belmont]

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This commit is contained in:
R. Belmont 2012-10-26 22:05:32 +00:00
parent bd5a8dd4f5
commit a9b74bf2a3
1 changed files with 15 additions and 19 deletions
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34
src/emu/sound/fm2612.c
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@ -26,7 +26,7 @@
**
** - fixed LFO implementation:
** .added support for CH3 special mode: fixes various sound effects (birds in Warlock, bug sound in Aladdin...)
** .modified LFO behavior when switched off (AM/PM current level is held) and on (LFO step is reseted): fixes intro in Spider-Man & Venom : Separation Anxiety
** .inverted LFO AM waveform: fixes Spider-Man & Venom : Separation Anxiety (intro), California Games (surfing event)
** .improved LFO timing accuracy: now updated AFTER sample output, like EG/PG updates, and without any precision loss anymore.
** - improved internal timers emulation
** - adjusted lowest EG rates increment values
@ -146,7 +146,7 @@
#define TYPE_YM2203 (TYPE_SSG)
#define TYPE_YM2608 (TYPE_SSG |TYPE_LFOPAN |TYPE_6CH |TYPE_ADPCM)
#define TYPE_YM2608 (TYPE_SSG |TYPE_LFO= PAN |TYPE_6CH |TYPE_ADPCM)
#define TYPE_YM2610 (TYPE_SSG |TYPE_LFOPAN |TYPE_6CH |TYPE_ADPCM |TYPE_2610)
#define TYPE_YM2612 (TYPE_DAC |TYPE_LFOPAN |TYPE_6CH)
@ -1144,10 +1144,10 @@ INLINE void set_ar_ksr(UINT8 type, FM_CH *CH,FM_SLOT *SLOT,int v)
CH->SLOT[SLOT1].Incr=-1;
}
/* Even if it seems unnecessary, in some odd case, KSR and KC are both modified */
/* Even if it seems unnecessary, in some odd case, KSR and KC are modified */
/* and could result in SLOT->kc remaining unchanged. */
/* In such case, AR values would not be recalculated despite SLOT->ar has changed */
/* This fixes the introduction music of Batman & Robin (Eke-Eke) */
/* This actually fixes the intro of "The Adventures of Batman & Robin" (Eke-Eke) */
if ((SLOT->ar + SLOT->ksr) < 94 /*32+62*/)
{
SLOT->eg_sh_ar = eg_rate_shift [SLOT->ar + SLOT->ksr ];
@ -1209,12 +1209,12 @@ INLINE void advance_lfo(FM_OPN *OPN)
/* There are 128 LFO steps */
OPN->lfo_cnt = ( OPN->lfo_cnt + 1 ) & 127;
/* triangle */
/* AM: 0 to 126 step +2, 126 to 0 step -2 */
/* triangle (inverted) */
/* AM: from 126 to 0 step -2, 0 to 126 step +2 */
if (OPN->lfo_cnt<64)
OPN->LFO_AM = OPN->lfo_cnt * 2;
OPN->LFO_AM = (OPN->lfo_cnt ^ 63) << 1;
else
OPN->LFO_AM = 126 - ((OPN->lfo_cnt&63) * 2);
OPN->LFO_AM = (OPN->lfo_cnt & 63) << 1;
/* PM works with 4 times slower clock */
OPN->LFO_PM = OPN->lfo_cnt >> 2;
@ -1592,12 +1592,12 @@ INLINE signed int op_calc1(UINT32 phase, unsigned int env, signed int pm)
INLINE void chan_calc(YM2612 *F2612, FM_OPN *OPN, FM_CH *CH)
{
UINT32 AM = OPN->LFO_AM >> CH->ams;
unsigned int eg_out = volume_calc(&CH->SLOT[SLOT1]);
OPN->m2 = OPN->c1 = OPN->c2 = OPN->mem = 0;
*CH->mem_connect = CH->mem_value; /* restore delayed sample (MEM) value to m2 or c2 */
unsigned int eg_out = volume_calc(&CH->SLOT[SLOT1]);
{
INT32 out = CH->op1_out[0] + CH->op1_out[1];
CH->op1_out[0] = CH->op1_out[1];
@ -1737,20 +1737,16 @@ static void OPNWriteMode(FM_OPN *OPN, int r, int v)
case 0x22: /* LFO FREQ (YM2608/YM2610/YM2610B/YM2612) */
if (v&8) /* LFO enabled ? */
{
if (!OPN->lfo_timer_overflow)
{
/* restart LFO */
OPN->lfo_cnt = 0;
OPN->lfo_timer = 0;
OPN->LFO_AM = 0;
OPN->LFO_PM = 0;
}
OPN->lfo_timer_overflow = lfo_samples_per_step[v&7] << LFO_SH;
}
else
{
/* hold LFO waveform in reset state */
OPN->lfo_timer_overflow = 0;
OPN->lfo_timer = 0;
OPN->lfo_cnt = 0;
OPN->LFO_PM = 0;
OPN->LFO_AM = 126;
}
break;
case 0x24: /* timer A High 8*/
@ -2418,7 +2414,7 @@ void ym2612_reset_chip(void *chip)
OPN->lfo_timer = 0;
OPN->lfo_cnt = 0;
OPN->LFO_AM = 0;
OPN->LFO_AM = 126;
OPN->LFO_PM = 0;
OPN->ST.status = 0;