The-Homebrew-Cloud/Genesis-Plus-GX
2
0
Fork 0
mirror of https://github.com/ekeeke/Genesis-Plus-GX.git synced 2024-12-24 18:21:50 +01:00
Code Issues Packages Projects Releases Wiki Activity

small fix to SSG-EG emulation

Browse Source
This commit is contained in:
ekeeke31 2009-02-27 09:09:06 +00:00
parent a857fb3990
commit 914b8d22f2
1 changed files with 88 additions and 66 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

154
source/sound/fm.c
View File

@ -467,25 +467,25 @@ static INT32 lfo_pm_table[128*8*32]; /* 128 combinations of 7 bits meaningful (o
/* struct describing a single operator (SLOT) */
typedef struct
{
INT32 *DT; /* detune :dt_tab[DT] */
UINT8 KSR; /* key scale rate :3-KSR */
UINT32 ar; /* attack rate */
UINT32 d1r; /* decay rate */
UINT32 d2r; /* sustain rate */
UINT32 rr; /* release rate */
UINT8 ksr; /* key scale rate :kcode>>(3-KSR) */
UINT32 mul; /* multiple :ML_TABLE[ML] */
INT32 *DT; /* detune :dt_tab[DT] */
UINT8 KSR; /* key scale rate :3-KSR */
UINT32 ar; /* attack rate */
UINT32 d1r; /* decay rate */
UINT32 d2r; /* sustain rate */
UINT32 rr; /* release rate */
UINT8 ksr; /* key scale rate :kcode>>(3-KSR) */
UINT32 mul; /* multiple :ML_TABLE[ML] */
/* Phase Generator */
UINT32 phase; /* phase counter */
INT32 Incr; /* phase step */
UINT32 phase; /* phase counter */
INT32 Incr; /* phase step */
/* Envelope Generator */
UINT8 state; /* phase type */
UINT32 tl; /* total level: TL << 3 */
INT32 volume; /* envelope counter */
UINT32 sl; /* sustain level:sl_table[SL] */
UINT32 vol_out; /* current output from EG circuit (without AM from LFO) */
UINT8 state; /* phase type */
UINT32 tl; /* total level: TL << 3 */
INT32 volume; /* envelope counter */
UINT32 sl; /* sustain level:sl_table[SL] */
UINT32 vol_out; /* current output from EG circuit (without AM from LFO) */
UINT8 eg_sh_ar; /* (attack state) */
UINT8 eg_sel_ar; /* (attack state) */
@ -496,13 +496,13 @@ typedef struct
UINT8 eg_sh_rr; /* (release state) */
UINT8 eg_sel_rr; /* (release state) */
UINT8 ssg; /* SSG-EG waveform */
UINT8 ssgn; /* SSG-EG negated output */
UINT8 ssg; /* SSG-EG waveform */
UINT8 ssgn; /* SSG-EG negated output */
UINT8 key; /* 0=last key was KEY OFF, 1=KEY ON */
UINT8 key; /* 0=last key was KEY OFF, 1=KEY ON */
/* LFO */
UINT32 AMmask; /* AM enable flag */
UINT32 AMmask; /* AM enable flag */
} FM_SLOT;
@ -510,44 +510,44 @@ typedef struct
{
FM_SLOT SLOT[4]; /* four SLOTs (operators) */
UINT8 ALGO; /* algorithm */
UINT8 FB; /* feedback shift */
INT32 op1_out[2]; /* op1 output for feedback */
UINT8 ALGO; /* algorithm */
UINT8 FB; /* feedback shift */
INT32 op1_out[2]; /* op1 output for feedback */
INT32 *connect1; /* SLOT1 output pointer */
INT32 *connect3; /* SLOT3 output pointer */
INT32 *connect2; /* SLOT2 output pointer */
INT32 *connect4; /* SLOT4 output pointer */
INT32 *connect1; /* SLOT1 output pointer */
INT32 *connect3; /* SLOT3 output pointer */
INT32 *connect2; /* SLOT2 output pointer */
INT32 *connect4; /* SLOT4 output pointer */
INT32 *mem_connect; /* where to put the delayed sample (MEM) */
INT32 mem_value; /* delayed sample (MEM) value */
INT32 *mem_connect; /* where to put the delayed sample (MEM) */
INT32 mem_value; /* delayed sample (MEM) value */
INT32 pms; /* channel PMS */
UINT8 ams; /* channel AMS */
INT32 pms; /* channel PMS */
UINT8 ams; /* channel AMS */
UINT32 fc; /* fnum,blk:adjusted to sample rate */
UINT8 kcode; /* key code */
UINT8 kcode; /* key code */
UINT32 block_fnum; /* current blk/fnum value for this slot (can be different betweeen slots of one channel in 3slot mode) */
} FM_CH;
typedef struct
{
UINT32 clock; /* master clock (Hz) */
UINT32 rate; /* sampling rate (Hz) */
double freqbase; /* frequency base */
UINT16 address; /* address register */
UINT8 status; /* status flag */
UINT32 mode; /* mode CSM / 3SLOT */
UINT8 fn_h; /* freq latch */
INT32 TimerBase; /* Timer base time */
INT32 TA; /* timer a value */
INT32 TAL; /* timer a base */
INT32 TAC; /* timer a counter */
INT32 TB; /* timer b value */
INT32 TBL; /* timer b base */
INT32 TBC; /* timer b counter */
INT32 dt_tab[8][32]; /* DeTune table */
UINT32 clock; /* master clock (Hz) */
UINT32 rate; /* sampling rate (Hz) */
double freqbase; /* frequency base */
UINT16 address; /* address register */
UINT8 status; /* status flag */
UINT32 mode; /* mode CSM / 3SLOT */
UINT8 fn_h; /* freq latch */
INT32 TimerBase; /* Timer base time */
INT32 TA; /* timer a value */
INT32 TAL; /* timer a base */
INT32 TAC; /* timer a counter */
INT32 TB; /* timer b value */
INT32 TBL; /* timer b base */
INT32 TBC; /* timer b counter */
INT32 dt_tab[8][32]; /* DeTune table */
} FM_ST;
@ -560,10 +560,10 @@ typedef struct
typedef struct
{
UINT32 fc[3]; /* fnum3,blk3: calculated */
UINT8 fn_h; /* freq3 latch */
UINT8 kcode[3]; /* key code */
UINT8 fn_h; /* freq3 latch */
UINT8 kcode[3]; /* key code */
UINT32 block_fnum[3]; /* current fnum value for this slot (can be different betweeen slots of one channel in 3slot mode) */
UINT8 key_csm; /* 1: KEY ON event occured in CSM mode */
UINT8 key_csm; /* CSM mode Key-ON flag */
} FM_3SLOT;
@ -622,7 +622,7 @@ INLINE void FM_KEYON(FM_CH *CH , int s )
{
FM_SLOT *SLOT = &CH->SLOT[s];
if( !SLOT->key && !ym2612.OPN.SL3.key_csm)
if (!SLOT->key && !ym2612.OPN.SL3.key_csm)
{
/* restart Phase Generator */
SLOT->phase = 0;
@ -657,17 +657,27 @@ INLINE void FM_KEYOFF(FM_CH *CH , int s )
{
FM_SLOT *SLOT = &CH->SLOT[s];
if( SLOT->key && !ym2612.OPN.SL3.key_csm)
if (SLOT->key && !ym2612.OPN.SL3.key_csm)
{
if (SLOT->state>EG_REL)
{
SLOT->state = EG_REL; /* phase -> Release */
/* SSG-EG */
if ((SLOT->ssg&0x08) && (SLOT->ssgn ^ (SLOT->ssg&0x04)))
/* SSG-EG specific update */
if (SLOT->ssg&0x08)
{
/* recalculate proper volume */
SLOT->volume = ((UINT32)SLOT->volume ^ 0x1FF) + 1; /* Invert Attenuation */
/* convert EG attenuation level */
if (SLOT->ssgn ^ (SLOT->ssg&0x04))
SLOT->volume = ((UINT32)SLOT->volume ^ 0x1FF) + 1;
/* force EG attenuation level */
if (SLOT->volume >= 0x200)
{
SLOT->volume = MAX_ATT_INDEX;
SLOT->state = EG_OFF;
}
/* recalculate EG output */
SLOT->vol_out = (UINT32)SLOT->volume + SLOT->tl;
}
}
@ -680,7 +690,7 @@ INLINE void FM_KEYON_CSM(FM_CH *CH , int s )
{
FM_SLOT *SLOT = &CH->SLOT[s];
if( !SLOT->key && !ym2612.OPN.SL3.key_csm)
if (!SLOT->key && !ym2612.OPN.SL3.key_csm)
{
/* restart Phase Generator */
SLOT->phase = 0;
@ -712,17 +722,27 @@ INLINE void FM_KEYON_CSM(FM_CH *CH , int s )
INLINE void FM_KEYOFF_CSM(FM_CH *CH , int s )
{
FM_SLOT *SLOT = &CH->SLOT[s];
if( !SLOT->key )
if (!SLOT->key)
{
if (SLOT->state>EG_REL)
{
SLOT->state = EG_REL; /* phase -> Release */
/* SSG-EG */
if ((SLOT->ssg&0x08) && (SLOT->ssgn ^ (SLOT->ssg&0x04)))
/* SSG-EG specific update */
if (SLOT->ssg&0x08)
{
/* recalculate proper volume */
SLOT->volume = ((UINT32)SLOT->volume ^ 0x1FF) + 1; /* Invert Attenuation */
/* convert EG attenuation level */
if (SLOT->ssgn ^ (SLOT->ssg&0x04))
SLOT->volume = ((UINT32)SLOT->volume ^ 0x1FF) + 1;
/* force EG attenuation level */
if (SLOT->volume >= 0x200)
{
SLOT->volume = MAX_ATT_INDEX;
SLOT->state = EG_OFF;
}
/* recalculate EG output */
SLOT->vol_out = (UINT32)SLOT->volume + SLOT->tl;
}
}
@ -1153,14 +1173,14 @@ INLINE void update_ssg_eg_channel(FM_SLOT *SLOT)
do
{
/* detect SSG-EG transition */
/* this is not required during release phase as the attenuation is set to MAX and output invert flag is not used */
/* this is not required during release phase as the attenuation has been forced to MAX and output invert flag is not used */
/* if an Attack Phase is programmed, inversion can occur on each sample */
if ((SLOT->ssg & 0x08) && (SLOT->volume >= 0x200) && (SLOT->state > EG_REL))
{
if (SLOT->ssg & 0x01) /* bit 0 = hold SSG-EG */
{
/* set inversion flag */
if ((SLOT->ssg & 0x02) && !SLOT->ssgn)
/* force inversion flag */
if (SLOT->ssg & 0x02)
SLOT->ssgn = 4;
/* force attenuation level */
@ -1170,8 +1190,10 @@ INLINE void update_ssg_eg_channel(FM_SLOT *SLOT)
else /* loop SSG-EG */
{
/* toggle output inversion flag or reset Phase Generator */
if (SLOT->ssg & 0x02) SLOT->ssgn ^= 4;
else SLOT->phase = 0;
if (SLOT->ssg & 0x02)
SLOT->ssgn ^= 4;
else
SLOT->phase = 0;
/* same as Key ON */
if (SLOT->state != EG_ATT)