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[Core/Sound] fixed MAME YM2413 core EG behavior for fastest attack rates (verified on YM2413 real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2017-01-26)

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ekeeke 2021-04-24 10:27:59 +02:00
parent 4feeb7d02e
commit ca484e9c56
5 changed files with 28 additions and 10 deletions
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3
HISTORY.txt
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@ -153,7 +153,8 @@ Genesis Plus GX 1.7.5 (xx/xx/xxxx) (Eke-Eke)
* fixed YM2413 carrier/modulator phase reset after channel Key ON (Japanese Master System BIOS music)
* fixed YM2413 intruments ROM (verified on YM2413B die)
* fixed YM2413 EG resolution bits (verified on YM2413B die)
* fixed YM2413 EG "dump" rate (verified on YM2413 hardware)
* fixed YM2413 EG dump rate (verified on YM2413 hardware)
* fixed YM2413 EG behavior for fastest attack rates (verified on YM2413 hardware)
[Gamecube/Wii]
---------------

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35
core/sound/ym2413.c
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@ -32,7 +32,8 @@ to do:
/** 2021/04/23: fixed synchronization of carrier/modulator phase reset after channel Key ON (fixes Japanese Master System BIOS music) **/
/** 2021/04/24: fixed intruments ROM (verified on YM2413B die, cf. https://siliconpr0n.org/archive/doku.php?id=vendor:yamaha:opl2#ym2413_instrument_rom) **/
/** 2021/04/24: fixed EG resolution bits (verified on YM2413B die, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2015-03-20) **/
/** 2021/04/24: fixed EG "dump" rate (verified on YM2413 real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2015-12-31) **/
/** 2021/04/24: fixed EG dump rate (verified on YM2413 real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2015-12-31) **/
/** 2021/04/25: fixed EG behavior for fastest attack rates (verified on YM2413 real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2017-01-26) **/
#include "shared.h"
@ -246,8 +247,8 @@ static const unsigned char eg_inc[15*RATE_STEPS]={
/*10 */ 2,4, 2,4, 2,4, 2,4, /* rate 14 2 */
/*11 */ 2,4, 4,4, 2,4, 4,4, /* rate 14 3 */
/*12 */ 4,4, 4,4, 4,4, 4,4, /* rates 15 0, 15 1, 15 2, 15 3 (increment by 4) */
/*13 */ 8,8, 8,8, 8,8, 8,8, /* rates 15 2, 15 3 for attack */
/*12 */ 4,4, 4,4, 4,4, 4,4, /* rates 15 0, 15 1, 15 2, 15 3 for decay (increment by 4) */
/*13 */ 8,8, 8,8, 8,8, 8,8, /* rates 15 0, 15 1, 15 2, 15 3 for attack (not used as attack phase is skipped in these cases) */
/*14 */ 0,0, 0,0, 0,0, 0,0, /* infinity rates for attack and decay(s) */
};
@ -584,8 +585,18 @@ INLINE void advance(void)
/* attack phase should be started if attenuation is already maximal, without waiting for next envelope update (every 2 samples during dump phase) */
if ( op->volume >= MAX_ATT_INDEX )
{
op->volume = MAX_ATT_INDEX;
op->state = EG_ATT;
/* attack phase is skipped and envelope is forced to 0 when attack rate is set to 15.0-15.3 */
/* (verified on real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2017-01-26) */
if ((op->ar + op->ksr) < 16+60)
{
op->volume = MAX_ATT_INDEX;
op->state = EG_ATT;
}
else
{
op->volume = MIN_ATT_INDEX;
op->state = EG_DEC;
}
/*dump phase is performed by both operators in each channel*/
/*when CARRIER envelope gets down to zero level,
@ -1177,15 +1188,18 @@ INLINE void CALC_FCSLOT(YM2413_OPLL_CH *CH,YM2413_OPLL_SLOT *SLOT)
SLOT->ksr = ksr;
/* calculate envelope generator rates */
if ((SLOT->ar + SLOT->ksr) < 16+62)
if ((SLOT->ar + SLOT->ksr) < 16+60)
{
SLOT->eg_sh_ar = eg_rate_shift [SLOT->ar + SLOT->ksr ];
SLOT->eg_sel_ar = eg_rate_select[SLOT->ar + SLOT->ksr ];
}
else
{
/* attack phase is skipped in case attack rate is set to 15.0-15.3 before it is started */
/* during attack phase, when attack rate is changed to 15.0-15.3, attack phase is blocked */
/* (verified on real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2017-01-26) */
SLOT->eg_sh_ar = 0;
SLOT->eg_sel_ar = 13*RATE_STEPS;
SLOT->eg_sel_ar = 14*RATE_STEPS;
}
SLOT->eg_sh_dr = eg_rate_shift [SLOT->dr + SLOT->ksr ];
SLOT->eg_sel_dr = eg_rate_select[SLOT->dr + SLOT->ksr ];
@ -1260,15 +1274,18 @@ INLINE void set_ar_dr(int slot,int v)
SLOT->ar = (v>>4) ? 16 + ((v>>4) <<2) : 0;
if ((SLOT->ar + SLOT->ksr) < 16+62)
if ((SLOT->ar + SLOT->ksr) < 16+60)
{
SLOT->eg_sh_ar = eg_rate_shift [SLOT->ar + SLOT->ksr ];
SLOT->eg_sel_ar = eg_rate_select[SLOT->ar + SLOT->ksr ];
}
else
{
/* attack phase is skipped in case attack rate is set to 15.0-15.3 before it is started */
/* during attack phase, when attack rate is changed to 15.0-15.3, attack phase is blocked */
/* (verified on real hardware, cf. https://www.smspower.org/Development/YM2413ReverseEngineeringNotes2017-01-26) */
SLOT->eg_sh_ar = 0;
SLOT->eg_sel_ar = 13*RATE_STEPS;
SLOT->eg_sel_ar = 14*RATE_STEPS;
}
SLOT->dr = (v&0x0f)? 16 + ((v&0x0f)<<2) : 0;