The-Homebrew-Cloud/Genesis-Plus-GX
2
0
Fork 0
mirror of https://github.com/ekeeke/Genesis-Plus-GX.git synced 2025-01-12 19:29:07 +01:00
Code Issues Packages Projects Releases Wiki Activity

improved YM2612 emulation

Browse Source
This commit is contained in:
ekeeke31 2008-09-11 16:15:58 +00:00
parent 0c3c721bd0
commit fbbd1d6057
3 changed files with 54 additions and 43 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
history.txt
View File

@ -5,7 +5,7 @@ CURRENT:
--------- ---------
[Genesis] [Genesis]
- YM2612(MAME): improved Enveloppe Generator accuracy: fix tracks #3 and #9 in Mega Turrican - YM2612(MAME): improved Enveloppe Generator accuracy: fix tracks #3 and #9 in Mega Turrican
- YM2612(MAME): fixed SSG-EG emulation bug: fix Level 1 music in Alisia Dragoon
[NGC/Wii] [NGC/Wii]
- improved menu scrolling using Wiimote D-PAD - improved menu scrolling using Wiimote D-PAD

90
source/sound/fm.c
View File

@ -18,12 +18,12 @@
** - fixed CH3 CSM mode (credits to Nemesis) ** - fixed CH3 CSM mode (credits to Nemesis)
** - implemented PG overflow, aka "detune bug" (Ariel, Comix Zone, Shaq Fu, Spiderman,...), credits to Nemesis ** - implemented PG overflow, aka "detune bug" (Ariel, Comix Zone, Shaq Fu, Spiderman,...), credits to Nemesis
** - fixed SSG-EG support, credits to Nemesis ** - fixed SSG-EG support, credits to Nemesis
** - modified EG rates and frequency, tested by Nemesis on real hardware ** - modified EG rates, tested by Nemesis on real hardware
** - fixed EG attenuation level on KEY ON (Ecco 2 splash sound) ** - fixed EG attenuation level on KEY ON (Ecco 2 splash sound)
** - fixed LFO phase update for CH3 special mode (Warlock, Alladin), thanks to AamirM ** - fixed LFO phase update for CH3 special mode (Warlock, Alladin), thanks to AamirM
** - fixed Attack rate refresh (fix Batman&Robin introduction)$ ** - fixed Attack rate refresh (fix Batman&Robin introduction)$
** - fixed attenuation level when starting Substain Phase (Gynoug ?) ** - fixed attenuation level at the start of Substain (Gynoug ?)
** - fixed Enveloppe Generator updates in some specific cases (AR maximal and/or Susbstain Level minimal) ** - fixed EG updates in some specific cases (AR maximal and/or Susbstain Level minimal)
** **
** 03-08-2003 Jarek Burczynski: ** 03-08-2003 Jarek Burczynski:
** - fixed YM2608 initial values (after the reset) ** - fixed YM2608 initial values (after the reset)
@ -654,7 +654,7 @@ INLINE void FM_KEYON(FM_CH *CH , int s )
SLOT->key = 1; SLOT->key = 1;
SLOT->phase = 0; /* restart Phase Generator */ SLOT->phase = 0; /* restart Phase Generator */
SLOT->ssgn = (SLOT->ssg & 0x04) >> 1; SLOT->ssgn = (SLOT->ssg & 0x04) >> 1;
if ((SLOT->ar + SLOT->ksr) < 94 /*32+62*/) if ((SLOT->ar + SLOT->ksr) < 94 /*32+62*/)
{ {
SLOT->state = EG_ATT; /* phase -> Attack */ SLOT->state = EG_ATT; /* phase -> Attack */
@ -928,10 +928,7 @@ INLINE void advance_eg_channel(FM_SLOT *SLOT)
case EG_ATT: /* attack phase */ case EG_ATT: /* attack phase */
if (!(ym2612.OPN.eg_cnt & ((1<<SLOT->eg_sh_ar)-1))) if (!(ym2612.OPN.eg_cnt & ((1<<SLOT->eg_sh_ar)-1)))
{ {
SLOT->volume += (~SLOT->volume * SLOT->volume += (~SLOT->volume * (eg_inc[SLOT->eg_sel_ar + ((ym2612.OPN.eg_cnt>>SLOT->eg_sh_ar)&7)]))>>4;
(eg_inc[SLOT->eg_sel_ar + ((ym2612.OPN.eg_cnt>>SLOT->eg_sh_ar)&7)])
)>>4;
if (SLOT->volume <= MIN_ATT_INDEX) if (SLOT->volume <= MIN_ATT_INDEX)
{ {
SLOT->volume = MIN_ATT_INDEX; SLOT->volume = MIN_ATT_INDEX;
@ -1053,7 +1050,7 @@ INLINE void advance_eg_channel(FM_SLOT *SLOT)
out = (UINT32)SLOT->volume; out = (UINT32)SLOT->volume;
/* negate output (changes come from alternate bit, init comes from attack bit) */ /* negate output (changes come from alternate bit, init comes from attack bit) */
if ((SLOT->ssg&0x08) && (SLOT->ssgn&2)) if ((SLOT->ssg&0x08) && (SLOT->ssgn&2) && (SLOT->state > EG_REL))
out ^= MAX_ATT_INDEX; out ^= MAX_ATT_INDEX;
/* we need to store the result here because we are going to change ssgn /* we need to store the result here because we are going to change ssgn
@ -1206,10 +1203,10 @@ INLINE void chan_calc(FM_CH *CH)
/* add support for 3 slot mode */ /* add support for 3 slot mode */
if ((ym2612.OPN.ST.mode & 0xC0) && (CH == &ym2612.CH[2])) if ((ym2612.OPN.ST.mode & 0xC0) && (CH == &ym2612.CH[2]))
{ {
update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT1], ym2612.CH[2].pms, ym2612.OPN.SL3.block_fnum[1]); update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT1], CH->pms, ym2612.OPN.SL3.block_fnum[1]);
update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT2], ym2612.CH[2].pms, ym2612.OPN.SL3.block_fnum[2]); update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT2], CH->pms, ym2612.OPN.SL3.block_fnum[2]);
update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT3], ym2612.CH[2].pms, ym2612.OPN.SL3.block_fnum[0]); update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT3], CH->pms, ym2612.OPN.SL3.block_fnum[0]);
update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT4], ym2612.CH[2].pms, ym2612.CH[2].block_fnum); update_phase_lfo_slot(&ym2612.CH[2].SLOT[SLOT4], CH->pms, CH->block_fnum);
} }
else update_phase_lfo_channel(CH); else update_phase_lfo_channel(CH);
} }
@ -1404,22 +1401,33 @@ static int init_tables(void)
} }
/* CSM Key Controll */ /* CSM Key Controll (correct implementation, credits to Nemesis) */
INLINE void CSMKeyControll(FM_CH *CH) INLINE void CSMKeyControll(FM_CH *CH)
{ {
/* correct implementation (credits to Nemesis) */ /* all key on/off */
if (CH->SLOT[SLOT1].state == EG_REL)
{
FM_KEYON(CH,SLOT1);
FM_KEYOFF(CH,SLOT1);
}
/* all key on */ if (CH->SLOT[SLOT2].state == EG_REL)
FM_KEYON(CH,SLOT1); {
FM_KEYON(CH,SLOT2); FM_KEYON(CH,SLOT2);
FM_KEYON(CH,SLOT3); FM_KEYOFF(CH,SLOT2);
FM_KEYON(CH,SLOT4); }
/* all key off */ if (CH->SLOT[SLOT3].state == EG_REL)
FM_KEYOFF(CH,SLOT1); {
FM_KEYOFF(CH,SLOT2); FM_KEYON(CH,SLOT3);
FM_KEYOFF(CH,SLOT3); FM_KEYOFF(CH,SLOT3);
}
if (CH->SLOT[SLOT4].state == EG_REL)
{
FM_KEYON(CH,SLOT4);
FM_KEYOFF(CH,SLOT4); FM_KEYOFF(CH,SLOT4);
}
} }
static void INTERNAL_TIMER_A() static void INTERNAL_TIMER_A()
@ -1466,13 +1474,13 @@ static void OPNSetPres(int pres)
/* YM2612 running at original frequency (~53 kHz) */ /* YM2612 running at original frequency (~53 kHz) */
if (config.hq_fm) ym2612.OPN.ST.freqbase = 1.0; if (config.hq_fm) ym2612.OPN.ST.freqbase = 1.0;
ym2612.OPN.eg_timer_add = (UINT32)((1<<EG_SH) * ym2612.OPN.ST.freqbase);
ym2612.OPN.eg_timer_overflow = ( 3 ) * (1<<EG_SH);
/* timer increment in usecs (timers are incremented after each updated samples) */ /* timer increment in usecs (timers are incremented after each updated samples) */
ym2612.OPN.ST.TimerBase = (int) (ym2612.OPN.ST.freqbase * 4096.0); ym2612.OPN.ST.TimerBase = (int) (ym2612.OPN.ST.freqbase * 4096.0);
ym2612.OPN.eg_timer_add = (UINT32)((1<<EG_SH) * ym2612.OPN.ST.freqbase);
//ym2612.OPN.eg_timer_overflow = ( 3 ) * (1<<EG_SH);
ym2612.OPN.eg_timer_overflow = (351 * (1<<EG_SH)) / 144; /* correct frequency (Nemesis: tested on real HW) */
/* make time tables */ /* make time tables */
init_timetables(dt_tab); init_timetables(dt_tab);
@ -1785,21 +1793,6 @@ void YM2612UpdateOne(int **buffer, int length)
out_fm[4] = 0; out_fm[4] = 0;
out_fm[5] = 0; out_fm[5] = 0;
/* advance envelope generator */
ym2612.OPN.eg_timer += ym2612.OPN.eg_timer_add;
while (ym2612.OPN.eg_timer >= ym2612.OPN.eg_timer_overflow)
{
ym2612.OPN.eg_timer -= ym2612.OPN.eg_timer_overflow;
ym2612.OPN.eg_cnt++;
advance_eg_channel(&ym2612.CH[0].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[1].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[2].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[3].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[4].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[5].SLOT[SLOT1]);
}
/* calculate FM */ /* calculate FM */
chan_calc(&ym2612.CH[0]); chan_calc(&ym2612.CH[0]);
chan_calc(&ym2612.CH[1]); chan_calc(&ym2612.CH[1]);
@ -1814,6 +1807,21 @@ void YM2612UpdateOne(int **buffer, int length)
} }
else chan_calc(&ym2612.CH[5]); else chan_calc(&ym2612.CH[5]);
/* advance envelope generator */
ym2612.OPN.eg_timer += ym2612.OPN.eg_timer_add;
while (ym2612.OPN.eg_timer >= ym2612.OPN.eg_timer_overflow)
{
ym2612.OPN.eg_timer -= ym2612.OPN.eg_timer_overflow;
ym2612.OPN.eg_cnt++;
advance_eg_channel(&ym2612.CH[0].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[1].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[2].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[3].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[4].SLOT[SLOT1]);
advance_eg_channel(&ym2612.CH[5].SLOT[SLOT1]);
}
lt = ((out_fm[0]>>0) & ym2612.OPN.pan[0]); lt = ((out_fm[0]>>0) & ym2612.OPN.pan[0]);
rt = ((out_fm[0]>>0) & ym2612.OPN.pan[1]); rt = ((out_fm[0]>>0) & ym2612.OPN.pan[1]);
lt += ((out_fm[1]>>0) & ym2612.OPN.pan[2]); lt += ((out_fm[1]>>0) & ym2612.OPN.pan[2]);

5
source/sound/sound.c
View File

@ -218,9 +218,12 @@ void fm_restore(void)
/* write FM chip */ /* write FM chip */
void fm_write(unsigned int cpu, unsigned int address, unsigned int data) void fm_write(unsigned int cpu, unsigned int address, unsigned int data)
{ {
if (address & 1)
{
snd.fm.curStage = fm_sample_cnt(cpu); snd.fm.curStage = fm_sample_cnt(cpu);
fm_update(); fm_update();
_YM2612_Write(address & 3, data); }
_YM2612_Write(address & 3, data);
} }
/* read FM status */ /* read FM status */