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Genesis-Plus-GX/source/sound/ym2413.c
ekeeke31 8af85558d0 .fixed YM2413 context restore when changing options 
.added YM2413 context to Master System savestates
.removed support for older savestates format (1.3.x, 1.4.x), use 1.5.0 to convert old savestates to new (1.5.x) format
2011-04-30 12:56:01 +00:00

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/*
**
** File: ym2413.c - software implementation of YM2413
** FM sound generator type OPLL
**
** Copyright (C) 2002 Jarek Burczynski
**
** Version 1.0
**
**
to do:
- make sure of the sinus amplitude bits
- make sure of the EG resolution bits (looks like the biggest
modulation index generated by the modulator is 123, 124 = no modulation)
- find proper algorithm for attack phase of EG
- tune up instruments ROM
- support sample replay in test mode (it is NOT as simple as setting bit 0
in register 0x0f and using register 0x10 for sample data).
Which games use this feature ?
*/
/** EkeEke (2011): removed multiple chips support and cleaned code for Genesis Plus GX **/
#include <math.h>
#include "shared.h"
/* compiler dependence */
#define INLINE static __inline__
#define FREQ_SH 16 /* 16.16 fixed point (frequency calculations) */
#define EG_SH 16 /* 16.16 fixed point (EG timing) */
#define LFO_SH 24 /* 8.24 fixed point (LFO calculations) */
#define FREQ_MASK ((1<<FREQ_SH)-1)
/* envelope output entries */
#define ENV_BITS 10
#define ENV_LEN (1<<ENV_BITS)
#define ENV_STEP (128.0/ENV_LEN)
#define MAX_ATT_INDEX ((1<<(ENV_BITS-2))-1) /*255*/
#define MIN_ATT_INDEX (0)
/* sinwave entries */
#define SIN_BITS 10
#define SIN_LEN (1<<SIN_BITS)
#define SIN_MASK (SIN_LEN-1)
#define TL_RES_LEN (256) /* 8 bits addressing (real chip) */
/* register number to channel number , slot offset */
#define SLOT1 0
#define SLOT2 1
/* Envelope Generator phases */
#define EG_DMP 5
#define EG_ATT 4
#define EG_DEC 3
#define EG_SUS 2
#define EG_REL 1
#define EG_OFF 0
typedef struct
{
UINT32 ar; /* attack rate: AR<<2 */
UINT32 dr; /* decay rate: DR<<2 */
UINT32 rr; /* release rate:RR<<2 */
UINT8 KSR; /* key scale rate */
UINT8 ksl; /* keyscale level */
UINT8 ksr; /* key scale rate: kcode>>KSR */
UINT8 mul; /* multiple: mul_tab[ML] */
/* Phase Generator */
UINT32 phase; /* frequency counter */
UINT32 freq; /* frequency counter step */
UINT8 fb_shift; /* feedback shift value */
INT32 op1_out[2]; /* slot1 output for feedback */
/* Envelope Generator */
UINT8 eg_type; /* percussive/nonpercussive mode */
UINT8 state; /* phase type */
UINT32 TL; /* total level: TL << 2 */
INT32 TLL; /* adjusted now TL */
INT32 volume; /* envelope counter */
UINT32 sl; /* sustain level: sl_tab[SL] */
UINT8 eg_sh_dp; /* (dump state) */
UINT8 eg_sel_dp; /* (dump state) */
UINT8 eg_sh_ar; /* (attack state) */
UINT8 eg_sel_ar; /* (attack state) */
UINT8 eg_sh_dr; /* (decay state) */
UINT8 eg_sel_dr; /* (decay state) */
UINT8 eg_sh_rr; /* (release state for non-perc.) */
UINT8 eg_sel_rr; /* (release state for non-perc.) */
UINT8 eg_sh_rs; /* (release state for perc.mode) */
UINT8 eg_sel_rs; /* (release state for perc.mode) */
UINT32 key; /* 0 = KEY OFF, >0 = KEY ON */
/* LFO */
UINT32 AMmask; /* LFO Amplitude Modulation enable mask */
UINT8 vib; /* LFO Phase Modulation enable flag (active high)*/
/* waveform select */
unsigned int wavetable;
} YM2413_OPLL_SLOT;
typedef struct
{
YM2413_OPLL_SLOT SLOT[2];
/* phase generator state */
UINT32 block_fnum; /* block+fnum */
UINT32 fc; /* Freq. freqement base */
UINT32 ksl_base; /* KeyScaleLevel Base step */
UINT8 kcode; /* key code (for key scaling) */
UINT8 sus; /* sus on/off (release speed in percussive mode) */
} YM2413_OPLL_CH;
/* chip state */
typedef struct {
YM2413_OPLL_CH P_CH[9]; /* OPLL chips have 9 channels */
UINT8 instvol_r[9]; /* instrument/volume (or volume/volume in percussive mode) */
UINT32 eg_cnt; /* global envelope generator counter */
UINT32 eg_timer; /* global envelope generator counter works at frequency = chipclock/72 */
UINT32 eg_timer_add; /* step of eg_timer */
UINT32 eg_timer_overflow; /* envelope generator timer overlfows every 1 sample (on real chip) */
UINT8 rhythm; /* Rhythm mode */
/* LFO */
UINT32 lfo_am_cnt;
UINT32 lfo_am_inc;
UINT32 lfo_pm_cnt;
UINT32 lfo_pm_inc;
UINT32 noise_rng; /* 23 bit noise shift register */
UINT32 noise_p; /* current noise 'phase' */
UINT32 noise_f; /* current noise period */
/* instrument settings */
/*
0-user instrument
1-15 - fixed instruments
16 -bass drum settings
17,18 - other percussion instruments
*/
UINT8 inst_tab[19][8];
UINT32 fn_tab[1024]; /* fnumber->increment counter */
UINT8 address; /* address register */
UINT8 status; /* status flag */
double clock; /* master clock (Hz) */
int rate; /* sampling rate (Hz) */
} YM2413;
/* key scale level */
/* table is 3dB/octave, DV converts this into 6dB/octave */
/* 0.1875 is bit 0 weight of the envelope counter (volume) expressed in the 'decibel' scale */
#define DV (0.1875/1.0)
static const UINT32 ksl_tab[8*16]=
{
/* OCT 0 */
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
/* OCT 1 */
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
0.000/DV, 0.750/DV, 1.125/DV, 1.500/DV,
1.875/DV, 2.250/DV, 2.625/DV, 3.000/DV,
/* OCT 2 */
0.000/DV, 0.000/DV, 0.000/DV, 0.000/DV,
0.000/DV, 1.125/DV, 1.875/DV, 2.625/DV,
3.000/DV, 3.750/DV, 4.125/DV, 4.500/DV,
4.875/DV, 5.250/DV, 5.625/DV, 6.000/DV,
/* OCT 3 */
0.000/DV, 0.000/DV, 0.000/DV, 1.875/DV,
3.000/DV, 4.125/DV, 4.875/DV, 5.625/DV,
6.000/DV, 6.750/DV, 7.125/DV, 7.500/DV,
7.875/DV, 8.250/DV, 8.625/DV, 9.000/DV,
/* OCT 4 */
0.000/DV, 0.000/DV, 3.000/DV, 4.875/DV,
6.000/DV, 7.125/DV, 7.875/DV, 8.625/DV,
9.000/DV, 9.750/DV,10.125/DV,10.500/DV,
10.875/DV,11.250/DV,11.625/DV,12.000/DV,
/* OCT 5 */
0.000/DV, 3.000/DV, 6.000/DV, 7.875/DV,
9.000/DV,10.125/DV,10.875/DV,11.625/DV,
12.000/DV,12.750/DV,13.125/DV,13.500/DV,
13.875/DV,14.250/DV,14.625/DV,15.000/DV,
/* OCT 6 */
0.000/DV, 6.000/DV, 9.000/DV,10.875/DV,
12.000/DV,13.125/DV,13.875/DV,14.625/DV,
15.000/DV,15.750/DV,16.125/DV,16.500/DV,
16.875/DV,17.250/DV,17.625/DV,18.000/DV,
/* OCT 7 */
0.000/DV, 9.000/DV,12.000/DV,13.875/DV,
15.000/DV,16.125/DV,16.875/DV,17.625/DV,
18.000/DV,18.750/DV,19.125/DV,19.500/DV,
19.875/DV,20.250/DV,20.625/DV,21.000/DV
};
#undef DV
/* sustain level table (3dB per step) */
/* 0 - 15: 0, 3, 6, 9,12,15,18,21,24,27,30,33,36,39,42,45 (dB)*/
#define SC(db) (UINT32) ( db * (1.0/ENV_STEP) )
static const UINT32 sl_tab[16]={
SC( 0),SC( 1),SC( 2),SC(3 ),SC(4 ),SC(5 ),SC(6 ),SC( 7),
SC( 8),SC( 9),SC(10),SC(11),SC(12),SC(13),SC(14),SC(15)
};
#undef SC
#define RATE_STEPS (8)
static const unsigned char eg_inc[15*RATE_STEPS]={
/*cycle:0 1 2 3 4 5 6 7*/
/* 0 */ 0,1, 0,1, 0,1, 0,1, /* rates 00..12 0 (increment by 0 or 1) */
/* 1 */ 0,1, 0,1, 1,1, 0,1, /* rates 00..12 1 */
/* 2 */ 0,1, 1,1, 0,1, 1,1, /* rates 00..12 2 */
/* 3 */ 0,1, 1,1, 1,1, 1,1, /* rates 00..12 3 */
/* 4 */ 1,1, 1,1, 1,1, 1,1, /* rate 13 0 (increment by 1) */
/* 5 */ 1,1, 1,2, 1,1, 1,2, /* rate 13 1 */
/* 6 */ 1,2, 1,2, 1,2, 1,2, /* rate 13 2 */
/* 7 */ 1,2, 2,2, 1,2, 2,2, /* rate 13 3 */
/* 8 */ 2,2, 2,2, 2,2, 2,2, /* rate 14 0 (increment by 2) */
/* 9 */ 2,2, 2,4, 2,2, 2,4, /* rate 14 1 */
/*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 */
/*14 */ 0,0, 0,0, 0,0, 0,0, /* infinity rates for attack and decay(s) */
};
#define O(a) (a*RATE_STEPS)
/*note that there is no O(13) in this table - it's directly in the code */
static const unsigned char eg_rate_select[16+64+16]={ /* Envelope Generator rates (16 + 64 rates + 16 RKS) */
/* 16 infinite time rates */
O(14),O(14),O(14),O(14),O(14),O(14),O(14),O(14),
O(14),O(14),O(14),O(14),O(14),O(14),O(14),O(14),
/* rates 00-12 */
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
O( 0),O( 1),O( 2),O( 3),
/* rate 13 */
O( 4),O( 5),O( 6),O( 7),
/* rate 14 */
O( 8),O( 9),O(10),O(11),
/* rate 15 */
O(12),O(12),O(12),O(12),
/* 16 dummy rates (same as 15 3) */
O(12),O(12),O(12),O(12),O(12),O(12),O(12),O(12),
O(12),O(12),O(12),O(12),O(12),O(12),O(12),O(12),
};
#undef O
/*rate 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 */
/*shift 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 0 */
/*mask 8191, 4095, 2047, 1023, 511, 255, 127, 63, 31, 15, 7, 3, 1, 0, 0, 0 */
#define O(a) (a*1)
static const unsigned char eg_rate_shift[16+64+16]={ /* Envelope Generator counter shifts (16 + 64 rates + 16 RKS) */
/* 16 infinite time rates */
O(0),O(0),O(0),O(0),O(0),O(0),O(0),O(0),
O(0),O(0),O(0),O(0),O(0),O(0),O(0),O(0),
/* rates 00-12 */
O(13),O(13),O(13),O(13),
O(12),O(12),O(12),O(12),
O(11),O(11),O(11),O(11),
O(10),O(10),O(10),O(10),
O( 9),O( 9),O( 9),O( 9),
O( 8),O( 8),O( 8),O( 8),
O( 7),O( 7),O( 7),O( 7),
O( 6),O( 6),O( 6),O( 6),
O( 5),O( 5),O( 5),O( 5),
O( 4),O( 4),O( 4),O( 4),
O( 3),O( 3),O( 3),O( 3),
O( 2),O( 2),O( 2),O( 2),
O( 1),O( 1),O( 1),O( 1),
/* rate 13 */
O( 0),O( 0),O( 0),O( 0),
/* rate 14 */
O( 0),O( 0),O( 0),O( 0),
/* rate 15 */
O( 0),O( 0),O( 0),O( 0),
/* 16 dummy rates (same as 15 3) */
O( 0),O( 0),O( 0),O( 0),O( 0),O( 0),O( 0),O( 0),
O( 0),O( 0),O( 0),O( 0),O( 0),O( 0),O( 0),O( 0),
};
#undef O
/* multiple table */
#define ML 2
static const UINT8 mul_tab[16]= {
/* 1/2, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,10,12,12,15,15 */
0.50*ML, 1.00*ML, 2.00*ML, 3.00*ML, 4.00*ML, 5.00*ML, 6.00*ML, 7.00*ML,
8.00*ML, 9.00*ML,10.00*ML,10.00*ML,12.00*ML,12.00*ML,15.00*ML,15.00*ML
};
#undef ML
/* TL_TAB_LEN is calculated as:
* 11 - sinus amplitude bits (Y axis)
* 2 - sinus sign bit (Y axis)
* TL_RES_LEN - sinus resolution (X axis)
*/
#define TL_TAB_LEN (11*2*TL_RES_LEN)
static signed int tl_tab[TL_TAB_LEN];
#define ENV_QUIET (TL_TAB_LEN>>5)
/* sin waveform table in 'decibel' scale */
/* two waveforms on OPLL type chips */
static unsigned int sin_tab[SIN_LEN * 2];
/* LFO Amplitude Modulation table (verified on real YM3812)
27 output levels (triangle waveform); 1 level takes one of: 192, 256 or 448 samples
Length: 210 elements.
Each of the elements has to be repeated
exactly 64 times (on 64 consecutive samples).
The whole table takes: 64 * 210 = 13440 samples.
We use data>>1, until we find what it really is on real chip...
*/
#define LFO_AM_TAB_ELEMENTS 210
static const UINT8 lfo_am_table[LFO_AM_TAB_ELEMENTS] = {
0,0,0,0,0,0,0,
1,1,1,1,
2,2,2,2,
3,3,3,3,
4,4,4,4,
5,5,5,5,
6,6,6,6,
7,7,7,7,
8,8,8,8,
9,9,9,9,
10,10,10,10,
11,11,11,11,
12,12,12,12,
13,13,13,13,
14,14,14,14,
15,15,15,15,
16,16,16,16,
17,17,17,17,
18,18,18,18,
19,19,19,19,
20,20,20,20,
21,21,21,21,
22,22,22,22,
23,23,23,23,
24,24,24,24,
25,25,25,25,
26,26,26,
25,25,25,25,
24,24,24,24,
23,23,23,23,
22,22,22,22,
21,21,21,21,
20,20,20,20,
19,19,19,19,
18,18,18,18,
17,17,17,17,
16,16,16,16,
15,15,15,15,
14,14,14,14,
13,13,13,13,
12,12,12,12,
11,11,11,11,
10,10,10,10,
9,9,9,9,
8,8,8,8,
7,7,7,7,
6,6,6,6,
5,5,5,5,
4,4,4,4,
3,3,3,3,
2,2,2,2,
1,1,1,1
};
/* LFO Phase Modulation table (verified on real YM2413) */
static const INT8 lfo_pm_table[8*8] = {
/* FNUM2/FNUM = 0 00xxxxxx (0x0000) */
0, 0, 0, 0, 0, 0, 0, 0,
/* FNUM2/FNUM = 0 01xxxxxx (0x0040) */
1, 0, 0, 0,-1, 0, 0, 0,
/* FNUM2/FNUM = 0 10xxxxxx (0x0080) */
2, 1, 0,-1,-2,-1, 0, 1,
/* FNUM2/FNUM = 0 11xxxxxx (0x00C0) */
3, 1, 0,-1,-3,-1, 0, 1,
/* FNUM2/FNUM = 1 00xxxxxx (0x0100) */
4, 2, 0,-2,-4,-2, 0, 2,
/* FNUM2/FNUM = 1 01xxxxxx (0x0140) */
5, 2, 0,-2,-5,-2, 0, 2,
/* FNUM2/FNUM = 1 10xxxxxx (0x0180) */
6, 3, 0,-3,-6,-3, 0, 3,
/* FNUM2/FNUM = 1 11xxxxxx (0x01C0) */
7, 3, 0,-3,-7,-3, 0, 3,
};
/* This is not 100% perfect yet but very close */
/*
- multi parameters are 100% correct (instruments and drums)
- LFO PM and AM enable are 100% correct
- waveform DC and DM select are 100% correct
*/
static unsigned char table[19][8] = {
/* MULT MULT modTL DcDmFb AR/DR AR/DR SL/RR SL/RR */
/* 0 1 2 3 4 5 6 7 */
{0x49, 0x4c, 0x4c, 0x12, 0x00, 0x00, 0x00, 0x00 }, //0
{0x61, 0x61, 0x1e, 0x17, 0xf0, 0x78, 0x00, 0x17 }, //1
{0x13, 0x41, 0x1e, 0x0d, 0xd7, 0xf7, 0x13, 0x13 }, //2
{0x13, 0x01, 0x99, 0x04, 0xf2, 0xf4, 0x11, 0x23 }, //3
{0x21, 0x61, 0x1b, 0x07, 0xaf, 0x64, 0x40, 0x27 }, //4
//{0x22, 0x21, 0x1e, 0x09, 0xf0, 0x76, 0x08, 0x28 }, //5
{0x22, 0x21, 0x1e, 0x06, 0xf0, 0x75, 0x08, 0x18 }, //5
//{0x31, 0x22, 0x16, 0x09, 0x90, 0x7f, 0x00, 0x08 }, //6
{0x31, 0x22, 0x16, 0x05, 0x90, 0x71, 0x00, 0x13 }, //6
{0x21, 0x61, 0x1d, 0x07, 0x82, 0x80, 0x10, 0x17 }, //7
{0x23, 0x21, 0x2d, 0x16, 0xc0, 0x70, 0x07, 0x07 }, //8
{0x61, 0x61, 0x1b, 0x06, 0x64, 0x65, 0x10, 0x17 }, //9
//{0x61, 0x61, 0x0c, 0x08, 0x85, 0xa0, 0x79, 0x07 }, //A
{0x61, 0x61, 0x0c, 0x18, 0x85, 0xf0, 0x70, 0x07 }, //A
{0x23, 0x01, 0x07, 0x11, 0xf0, 0xa4, 0x00, 0x22 }, //B
{0x97, 0xc1, 0x24, 0x07, 0xff, 0xf8, 0x22, 0x12 }, //C
//{0x61, 0x10, 0x0c, 0x08, 0xf2, 0xc4, 0x40, 0xc8 }, //D
{0x61, 0x10, 0x0c, 0x05, 0xf2, 0xf4, 0x40, 0x44 }, //D
{0x01, 0x01, 0x55, 0x03, 0xf3, 0x92, 0xf3, 0xf3 }, //E
{0x61, 0x41, 0x89, 0x03, 0xf1, 0xf4, 0xf0, 0x13 }, //F
/* drum instruments definitions */
/* MULTI MULTI modTL xxx AR/DR AR/DR SL/RR SL/RR */
/* 0 1 2 3 4 5 6 7 */
{0x01, 0x01, 0x16, 0x00, 0xfd, 0xf8, 0x2f, 0x6d },/* BD(multi verified, modTL verified, mod env - verified(close), carr. env verifed) */
{0x01, 0x01, 0x00, 0x00, 0xd8, 0xd8, 0xf9, 0xf8 },/* HH(multi verified), SD(multi not used) */
{0x05, 0x01, 0x00, 0x00, 0xf8, 0xba, 0x49, 0x55 },/* TOM(multi,env verified), TOP CYM(multi verified, env verified) */
};
static signed int output[2];
static UINT32 LFO_AM;
static INT32 LFO_PM;
/* emulated chip */
static YM2413 ym2413;
/* advance LFO to next sample */
INLINE void advance_lfo(void)
{
/* LFO */
ym2413.lfo_am_cnt += ym2413.lfo_am_inc;
if (ym2413.lfo_am_cnt >= (LFO_AM_TAB_ELEMENTS<<LFO_SH) ) /* lfo_am_table is 210 elements long */
ym2413.lfo_am_cnt -= (LFO_AM_TAB_ELEMENTS<<LFO_SH);
LFO_AM = lfo_am_table[ ym2413.lfo_am_cnt >> LFO_SH ] >> 1;
ym2413.lfo_pm_cnt += ym2413.lfo_pm_inc;
LFO_PM = (ym2413.lfo_pm_cnt>>LFO_SH) & 7;
}
/* advance to next sample */
INLINE void advance(void)
{
YM2413_OPLL_CH *CH;
YM2413_OPLL_SLOT *op;
unsigned int i;
/* Envelope Generator */
ym2413.eg_timer += ym2413.eg_timer_add;
while (ym2413.eg_timer >= ym2413.eg_timer_overflow)
{
ym2413.eg_timer -= ym2413.eg_timer_overflow;
ym2413.eg_cnt++;
for (i=0; i<9*2; i++)
{
CH = &ym2413.P_CH[i>>1];
op = &CH->SLOT[i&1];
switch(op->state)
{
case EG_DMP: /* dump phase */
/*dump phase is performed by both operators in each channel*/
/*when CARRIER envelope gets down to zero level,
** phases in BOTH opearators are reset (at the same time ?)
*/
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_dp)-1) ) )
{
op->volume += eg_inc[op->eg_sel_dp + ((ym2413.eg_cnt>>op->eg_sh_dp)&7)];
if ( op->volume >= MAX_ATT_INDEX )
{
op->volume = MAX_ATT_INDEX;
op->state = EG_ATT;
/* restart Phase Generator */
op->phase = 0;
}
}
break;
case EG_ATT: /* attack phase */
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_ar)-1) ) )
{
op->volume += (~op->volume *
(eg_inc[op->eg_sel_ar + ((ym2413.eg_cnt>>op->eg_sh_ar)&7)])
) >>2;
if (op->volume <= MIN_ATT_INDEX)
{
op->volume = MIN_ATT_INDEX;
op->state = EG_DEC;
}
}
break;
case EG_DEC: /* decay phase */
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_dr)-1) ) )
{
op->volume += eg_inc[op->eg_sel_dr + ((ym2413.eg_cnt>>op->eg_sh_dr)&7)];
if ( op->volume >= op->sl )
op->state = EG_SUS;
}
break;
case EG_SUS: /* sustain phase */
/* this is important behaviour:
one can change percusive/non-percussive modes on the fly and
the chip will remain in sustain phase - verified on real YM3812 */
if(op->eg_type) /* non-percussive mode (sustained tone) */
{
/* do nothing */
}
else /* percussive mode */
{
/* during sustain phase chip adds Release Rate (in percussive mode) */
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_rr)-1) ) )
{
op->volume += eg_inc[op->eg_sel_rr + ((ym2413.eg_cnt>>op->eg_sh_rr)&7)];
if ( op->volume >= MAX_ATT_INDEX )
op->volume = MAX_ATT_INDEX;
}
/* else do nothing in sustain phase */
}
break;
case EG_REL: /* release phase */
/* exclude modulators in melody channels from performing anything in this mode*/
/* allowed are only carriers in melody mode and rhythm slots in rhythm mode */
/*This table shows which operators and on what conditions are allowed to perform EG_REL:
(a) - always perform EG_REL
(n) - never perform EG_REL
(r) - perform EG_REL in Rhythm mode ONLY
0: 0 (n), 1 (a)
1: 2 (n), 3 (a)
2: 4 (n), 5 (a)
3: 6 (n), 7 (a)
4: 8 (n), 9 (a)
5: 10(n), 11(a)
6: 12(r), 13(a)
7: 14(r), 15(a)
8: 16(r), 17(a)
*/
if ( (i&1) || ((ym2413.rhythm&0x20) && (i>=12)) )/* exclude modulators */
{
if(op->eg_type) /* non-percussive mode (sustained tone) */
/*this is correct: use RR when SUS = OFF*/
/*and use RS when SUS = ON*/
{
if (CH->sus)
{
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_rs)-1) ) )
{
op->volume += eg_inc[op->eg_sel_rs + ((ym2413.eg_cnt>>op->eg_sh_rs)&7)];
if ( op->volume >= MAX_ATT_INDEX )
{
op->volume = MAX_ATT_INDEX;
op->state = EG_OFF;
}
}
}
else
{
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_rr)-1) ) )
{
op->volume += eg_inc[op->eg_sel_rr + ((ym2413.eg_cnt>>op->eg_sh_rr)&7)];
if ( op->volume >= MAX_ATT_INDEX )
{
op->volume = MAX_ATT_INDEX;
op->state = EG_OFF;
}
}
}
}
else /* percussive mode */
{
if ( !(ym2413.eg_cnt & ((1<<op->eg_sh_rs)-1) ) )
{
op->volume += eg_inc[op->eg_sel_rs + ((ym2413.eg_cnt>>op->eg_sh_rs)&7)];
if ( op->volume >= MAX_ATT_INDEX )
{
op->volume = MAX_ATT_INDEX;
op->state = EG_OFF;
}
}
}
}
break;
default:
break;
}
}
}
for (i=0; i<9*2; i++)
{
CH = &ym2413.P_CH[i/2];
op = &CH->SLOT[i&1];
/* Phase Generator */
if(op->vib)
{
UINT8 block;
unsigned int fnum_lfo = 8*((CH->block_fnum&0x01c0) >> 6);
unsigned int block_fnum = CH->block_fnum * 2;
signed int lfo_fn_table_index_offset = lfo_pm_table[LFO_PM + fnum_lfo ];
if (lfo_fn_table_index_offset) /* LFO phase modulation active */
{
block_fnum += lfo_fn_table_index_offset;
block = (block_fnum&0x1c00) >> 10;
op->phase += (ym2413.fn_tab[block_fnum&0x03ff] >> (7-block)) * op->mul;
}
else /* LFO phase modulation = zero */
{
op->phase += op->freq;
}
}
else /* LFO phase modulation disabled for this operator */
{
op->phase += op->freq;
}
}
/* The Noise Generator of the YM3812 is 23-bit shift register.
* Period is equal to 2^23-2 samples.
* Register works at sampling frequency of the chip, so output
* can change on every sample.
*
* Output of the register and input to the bit 22 is:
* bit0 XOR bit14 XOR bit15 XOR bit22
*
* Simply use bit 22 as the noise output.
*/
ym2413.noise_p += ym2413.noise_f;
i = ym2413.noise_p >> FREQ_SH; /* number of events (shifts of the shift register) */
ym2413.noise_p &= FREQ_MASK;
while (i)
{
/*
UINT32 j;
j = ( (chip->noise_rng) ^ (chip->noise_rng>>14) ^ (chip->noise_rng>>15) ^ (chip->noise_rng>>22) ) & 1;
chip->noise_rng = (j<<22) | (chip->noise_rng>>1);
*/
/*
Instead of doing all the logic operations above, we
use a trick here (and use bit 0 as the noise output).
The difference is only that the noise bit changes one
step ahead. This doesn't matter since we don't know
what is real state of the noise_rng after the reset.
*/
if (ym2413.noise_rng & 1) ym2413.noise_rng ^= 0x800302;
ym2413.noise_rng >>= 1;
i--;
}
}
INLINE signed int op_calc(UINT32 phase, unsigned int env, signed int pm, unsigned int wave_tab)
{
UINT32 p = (env<<5) + sin_tab[wave_tab + ((((signed int)((phase & ~FREQ_MASK) + (pm<<17))) >> FREQ_SH ) & SIN_MASK) ];
if (p >= TL_TAB_LEN)
return 0;
return tl_tab[p];
}
INLINE signed int op_calc1(UINT32 phase, unsigned int env, signed int pm, unsigned int wave_tab)
{
UINT32 p = (env<<5) + sin_tab[wave_tab + ((((signed int)((phase & ~FREQ_MASK) + pm)) >> FREQ_SH ) & SIN_MASK) ];
if (p >= TL_TAB_LEN)
return 0;
return tl_tab[p];
}
#define volume_calc(OP) ((OP)->TLL + ((UINT32)(OP)->volume) + (LFO_AM & (OP)->AMmask))
/* calculate output */
INLINE void chan_calc( YM2413_OPLL_CH *CH )
{
YM2413_OPLL_SLOT *SLOT;
unsigned int env;
signed int out;
signed int phase_modulation; /* phase modulation input (SLOT 2) */
/* SLOT 1 */
SLOT = &CH->SLOT[SLOT1];
env = volume_calc(SLOT);
out = SLOT->op1_out[0] + SLOT->op1_out[1];
SLOT->op1_out[0] = SLOT->op1_out[1];
phase_modulation = SLOT->op1_out[0];
SLOT->op1_out[1] = 0;
if( env < ENV_QUIET )
{
if (!SLOT->fb_shift)
out = 0;
SLOT->op1_out[1] = op_calc1(SLOT->phase, env, (out<<SLOT->fb_shift), SLOT->wavetable );
}
/* SLOT 2 */
SLOT++;
env = volume_calc(SLOT);
if( env < ENV_QUIET )
{
output[0] += op_calc(SLOT->phase, env, phase_modulation, SLOT->wavetable);
}
}
/*
operators used in the rhythm sounds generation process:
Envelope Generator:
channel operator register number Bass High Snare Tom Top
/ slot number TL ARDR SLRR Wave Drum Hat Drum Tom Cymbal
6 / 0 12 50 70 90 f0 +
6 / 1 15 53 73 93 f3 +
7 / 0 13 51 71 91 f1 +
7 / 1 16 54 74 94 f4 +
8 / 0 14 52 72 92 f2 +
8 / 1 17 55 75 95 f5 +
Phase Generator:
channel operator register number Bass High Snare Tom Top
/ slot number MULTIPLE Drum Hat Drum Tom Cymbal
6 / 0 12 30 +
6 / 1 15 33 +
7 / 0 13 31 + + +
7 / 1 16 34 ----- n o t u s e d -----
8 / 0 14 32 +
8 / 1 17 35 + +
channel operator register number Bass High Snare Tom Top
number number BLK/FNUM2 FNUM Drum Hat Drum Tom Cymbal
6 12,15 B6 A6 +
7 13,16 B7 A7 + + +
8 14,17 B8 A8 + + +
*/
/* calculate rhythm */
INLINE void rhythm_calc( YM2413_OPLL_CH *CH, unsigned int noise )
{
YM2413_OPLL_SLOT *SLOT;
signed int out;
unsigned int env;
signed int phase_modulation; /* phase modulation input (SLOT 2) */
/* Bass Drum (verified on real YM3812):
- depends on the channel 6 'connect' register:
when connect = 0 it works the same as in normal (non-rhythm) mode (op1->op2->out)
when connect = 1 _only_ operator 2 is present on output (op2->out), operator 1 is ignored
- output sample always is multiplied by 2
*/
/* SLOT 1 */
SLOT = &CH[6].SLOT[SLOT1];
env = volume_calc(SLOT);
out = SLOT->op1_out[0] + SLOT->op1_out[1];
SLOT->op1_out[0] = SLOT->op1_out[1];
phase_modulation = SLOT->op1_out[0];
SLOT->op1_out[1] = 0;
if( env < ENV_QUIET )
{
if (!SLOT->fb_shift)
out = 0;
SLOT->op1_out[1] = op_calc1(SLOT->phase, env, (out<<SLOT->fb_shift), SLOT->wavetable );
}
/* SLOT 2 */
SLOT++;
env = volume_calc(SLOT);
if( env < ENV_QUIET )
output[1] += op_calc(SLOT->phase, env, phase_modulation, SLOT->wavetable);
/* Phase generation is based on: */
// HH (13) channel 7->slot 1 combined with channel 8->slot 2 (same combination as TOP CYMBAL but different output phases)
// SD (16) channel 7->slot 1
// TOM (14) channel 8->slot 1
// TOP (17) channel 7->slot 1 combined with channel 8->slot 2 (same combination as HIGH HAT but different output phases)
/* Envelope generation based on: */
// HH channel 7->slot1
// SD channel 7->slot2
// TOM channel 8->slot1
// TOP channel 8->slot2
/* The following formulas can be well optimized.
I leave them in direct form for now (in case I've missed something).
*/
/* High Hat (verified on real YM3812) */
env = volume_calc(&CH[7].SLOT[SLOT1]);
if( env < ENV_QUIET )
{
/* high hat phase generation:
phase = d0 or 234 (based on frequency only)
phase = 34 or 2d0 (based on noise)
*/
/* base frequency derived from operator 1 in channel 7 */
unsigned char bit7 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>7)&1;
unsigned char bit3 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>3)&1;
unsigned char bit2 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>2)&1;
unsigned char res1 = (bit2 ^ bit7) | bit3;
/* when res1 = 0 phase = 0x000 | 0xd0; */
/* when res1 = 1 phase = 0x200 | (0xd0>>2); */
UINT32 phase = res1 ? (0x200|(0xd0>>2)) : 0xd0;
/* enable gate based on frequency of operator 2 in channel 8 */
unsigned char bit5e= ((CH[8].SLOT[SLOT2].phase>>FREQ_SH)>>5)&1;
unsigned char bit3e= ((CH[8].SLOT[SLOT2].phase>>FREQ_SH)>>3)&1;
unsigned char res2 = (bit3e | bit5e);
/* when res2 = 0 pass the phase from calculation above (res1); */
/* when res2 = 1 phase = 0x200 | (0xd0>>2); */
if (res2)
phase = (0x200|(0xd0>>2));
/* when phase & 0x200 is set and noise=1 then phase = 0x200|0xd0 */
/* when phase & 0x200 is set and noise=0 then phase = 0x200|(0xd0>>2), ie no change */
if (phase&0x200)
{
if (noise)
phase = 0x200|0xd0;
}
else
/* when phase & 0x200 is clear and noise=1 then phase = 0xd0>>2 */
/* when phase & 0x200 is clear and noise=0 then phase = 0xd0, ie no change */
{
if (noise)
phase = 0xd0>>2;
}
output[1] += op_calc(phase<<FREQ_SH, env, 0, CH[7].SLOT[SLOT1].wavetable);
}
/* Snare Drum (verified on real YM3812) */
env = volume_calc(&CH[7].SLOT[SLOT2]);
if( env < ENV_QUIET )
{
/* base frequency derived from operator 1 in channel 7 */
unsigned char bit8 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>8)&1;
/* when bit8 = 0 phase = 0x100; */
/* when bit8 = 1 phase = 0x200; */
UINT32 phase = bit8 ? 0x200 : 0x100;
/* Noise bit XOR'es phase by 0x100 */
/* when noisebit = 0 pass the phase from calculation above */
/* when noisebit = 1 phase ^= 0x100; */
/* in other words: phase ^= (noisebit<<8); */
if (noise)
phase ^= 0x100;
output[1] += op_calc(phase<<FREQ_SH, env, 0, CH[7].SLOT[SLOT2].wavetable);
}
/* Tom Tom (verified on real YM3812) */
env = volume_calc(&CH[8].SLOT[SLOT1]);
if( env < ENV_QUIET )
output[1] += op_calc(CH[8].SLOT[SLOT1].phase, env, 0, CH[8].SLOT[SLOT1].wavetable);
/* Top Cymbal (verified on real YM2413) */
env = volume_calc(&CH[8].SLOT[SLOT2]);
if( env < ENV_QUIET )
{
/* base frequency derived from operator 1 in channel 7 */
unsigned char bit7 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>7)&1;
unsigned char bit3 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>3)&1;
unsigned char bit2 = ((CH[7].SLOT[SLOT1].phase>>FREQ_SH)>>2)&1;
unsigned char res1 = (bit2 ^ bit7) | bit3;
/* when res1 = 0 phase = 0x000 | 0x100; */
/* when res1 = 1 phase = 0x200 | 0x100; */
UINT32 phase = res1 ? 0x300 : 0x100;
/* enable gate based on frequency of operator 2 in channel 8 */
unsigned char bit5e= ((CH[8].SLOT[SLOT2].phase>>FREQ_SH)>>5)&1;
unsigned char bit3e= ((CH[8].SLOT[SLOT2].phase>>FREQ_SH)>>3)&1;
unsigned char res2 = (bit3e | bit5e);
/* when res2 = 0 pass the phase from calculation above (res1); */
/* when res2 = 1 phase = 0x200 | 0x100; */
if (res2)
phase = 0x300;
output[1] += op_calc(phase<<FREQ_SH, env, 0, CH[8].SLOT[SLOT2].wavetable);
}
}
/* generic table initialize */
static int init_tables(void)
{
signed int i,x;
signed int n;
double o,m;
#ifdef NGC
u32 level = IRQ_Disable();
#endif
for (x=0; x<TL_RES_LEN; x++)
{
m = (1<<16) / pow(2, (x+1) * (ENV_STEP/4.0) / 8.0);
m = floor(m);
/* we never reach (1<<16) here due to the (x+1) */
/* result fits within 16 bits at maximum */
n = (int)m; /* 16 bits here */
n >>= 4; /* 12 bits here */
if (n&1) /* round to nearest */
n = (n>>1)+1;
else
n = n>>1;
/* 11 bits here (rounded) */
tl_tab[ x*2 + 0 ] = n;
tl_tab[ x*2 + 1 ] = -tl_tab[ x*2 + 0 ];
for (i=1; i<11; i++)
{
tl_tab[ x*2+0 + i*2*TL_RES_LEN ] = tl_tab[ x*2+0 ]>>i;
tl_tab[ x*2+1 + i*2*TL_RES_LEN ] = -tl_tab[ x*2+0 + i*2*TL_RES_LEN ];
}
}
for (i=0; i<SIN_LEN; i++)
{
/* non-standard sinus */
m = sin( ((i*2)+1) * M_PI / SIN_LEN ); /* checked against the real chip */
/* we never reach zero here due to ((i*2)+1) */
if (m>0.0)
o = 8*log(1.0/m)/log(2); /* convert to 'decibels' */
else
o = 8*log(-1.0/m)/log(2); /* convert to 'decibels' */
o = o / (ENV_STEP/4);
n = (int)(2.0*o);
if (n&1) /* round to nearest */
n = (n>>1)+1;
else
n = n>>1;
/* waveform 0: standard sinus */
sin_tab[ i ] = n*2 + (m>=0.0? 0: 1 );
/* waveform 1: __ __ */
/* / \____/ \____*/
/* output only first half of the sinus waveform (positive one) */
if (i & (1<<(SIN_BITS-1)) )
sin_tab[1*SIN_LEN+i] = TL_TAB_LEN;
else
sin_tab[1*SIN_LEN+i] = sin_tab[i];
}
#ifdef NGC
IRQ_Restore(level);
#endif
return 1;
}
static void OPLL_initalize(void)
{
int i;
/* frequency base */
double freqbase = (ym2413.clock / 72.0) / (double)ym2413.rate;
/* YM2413 running at original frequency */
if (config.hq_fm) freqbase = 1.0;
/* make fnumber -> increment counter table */
for( i = 0 ; i < 1024; i++ )
{
/* OPLL (YM2413) phase increment counter = 18bit */
ym2413.fn_tab[i] = (UINT32)( (double)i * 64 * freqbase * (1<<(FREQ_SH-10)) ); /* -10 because chip works with 10.10 fixed point, while we use 16.16 */
}
/* Amplitude modulation: 27 output levels (triangle waveform); 1 level takes one of: 192, 256 or 448 samples */
/* One entry from LFO_AM_TABLE lasts for 64 samples */
ym2413.lfo_am_inc = (1.0 / 64.0 ) * (1<<LFO_SH) * freqbase;
/* Vibrato: 8 output levels (triangle waveform); 1 level takes 1024 samples */
ym2413.lfo_pm_inc = (1.0 / 1024.0) * (1<<LFO_SH) * freqbase;
/* Noise generator: a step takes 1 sample */
ym2413.noise_f = (1.0 / 1.0) * (1<<FREQ_SH) * freqbase;
ym2413.eg_timer_add = (1<<EG_SH) * freqbase;
ym2413.eg_timer_overflow = ( 1 ) * (1<<EG_SH);
}
INLINE void KEY_ON(YM2413_OPLL_SLOT *SLOT, UINT32 key_set)
{
if( !SLOT->key )
{
/* do NOT restart Phase Generator (verified on real YM2413)*/
/* phase -> Dump */
SLOT->state = EG_DMP;
}
SLOT->key |= key_set;
}
INLINE void KEY_OFF(YM2413_OPLL_SLOT *SLOT, UINT32 key_clr)
{
if( SLOT->key )
{
SLOT->key &= key_clr;
if( !SLOT->key )
{
/* phase -> Release */
if (SLOT->state>EG_REL)
SLOT->state = EG_REL;
}
}
}
/* update phase increment counter of operator (also update the EG rates if necessary) */
INLINE void CALC_FCSLOT(YM2413_OPLL_CH *CH,YM2413_OPLL_SLOT *SLOT)
{
int ksr;
UINT32 SLOT_rs;
UINT32 SLOT_dp;
/* (frequency) phase increment counter */
SLOT->freq = CH->fc * SLOT->mul;
ksr = CH->kcode >> SLOT->KSR;
if( SLOT->ksr != ksr )
{
SLOT->ksr = ksr;
/* calculate envelope generator rates */
if ((SLOT->ar + SLOT->ksr) < 16+62)
{
SLOT->eg_sh_ar = eg_rate_shift [SLOT->ar + SLOT->ksr ];
SLOT->eg_sel_ar = eg_rate_select[SLOT->ar + SLOT->ksr ];
}
else
{
SLOT->eg_sh_ar = 0;
SLOT->eg_sel_ar = 13*RATE_STEPS;
}
SLOT->eg_sh_dr = eg_rate_shift [SLOT->dr + SLOT->ksr ];
SLOT->eg_sel_dr = eg_rate_select[SLOT->dr + SLOT->ksr ];
SLOT->eg_sh_rr = eg_rate_shift [SLOT->rr + SLOT->ksr ];
SLOT->eg_sel_rr = eg_rate_select[SLOT->rr + SLOT->ksr ];
}
if (CH->sus)
SLOT_rs = 16 + (5<<2);
else
SLOT_rs = 16 + (7<<2);
SLOT->eg_sh_rs = eg_rate_shift [SLOT_rs + SLOT->ksr ];
SLOT->eg_sel_rs = eg_rate_select[SLOT_rs + SLOT->ksr ];
SLOT_dp = 16 + (13<<2);
SLOT->eg_sh_dp = eg_rate_shift [SLOT_dp + SLOT->ksr ];
SLOT->eg_sel_dp = eg_rate_select[SLOT_dp + SLOT->ksr ];
}
/* set multi,am,vib,EG-TYP,KSR,mul */
INLINE void set_mul(int slot,int v)
{
YM2413_OPLL_CH *CH = &ym2413.P_CH[slot/2];
YM2413_OPLL_SLOT *SLOT = &CH->SLOT[slot&1];
SLOT->mul = mul_tab[v&0x0f];
SLOT->KSR = (v&0x10) ? 0 : 2;
SLOT->eg_type = (v&0x20);
SLOT->vib = (v&0x40);
SLOT->AMmask = (v&0x80) ? ~0 : 0;
CALC_FCSLOT(CH,SLOT);
}
/* set ksl, tl */
INLINE void set_ksl_tl(int chan,int v)
{
YM2413_OPLL_CH *CH = &ym2413.P_CH[chan];
/* modulator */
YM2413_OPLL_SLOT *SLOT = &CH->SLOT[SLOT1];
int ksl = v>>6; /* 0 / 1.5 / 3.0 / 6.0 dB/OCT */
SLOT->ksl = ksl ? 3-ksl : 31;
SLOT->TL = (v&0x3f)<<(ENV_BITS-2-7); /* 7 bits TL (bit 6 = always 0) */
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
}
/* set ksl , waveforms, feedback */
INLINE void set_ksl_wave_fb(int chan,int v)
{
YM2413_OPLL_CH *CH = &ym2413.P_CH[chan];
/* modulator */
YM2413_OPLL_SLOT *SLOT = &CH->SLOT[SLOT1];
SLOT->wavetable = ((v&0x08)>>3)*SIN_LEN;
SLOT->fb_shift = (v&7) ? (v&7) + 8 : 0;
/*carrier*/
SLOT = &CH->SLOT[SLOT2];
int ksl = v>>6; /* 0 / 1.5 / 3.0 / 6.0 dB/OCT */
SLOT->ksl = ksl ? 3-ksl : 31;
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
SLOT->wavetable = ((v&0x10)>>4)*SIN_LEN;
}
/* set attack rate & decay rate */
INLINE void set_ar_dr(int slot,int v)
{
YM2413_OPLL_CH *CH = &ym2413.P_CH[slot/2];
YM2413_OPLL_SLOT *SLOT = &CH->SLOT[slot&1];
SLOT->ar = (v>>4) ? 16 + ((v>>4) <<2) : 0;
if ((SLOT->ar + SLOT->ksr) < 16+62)
{
SLOT->eg_sh_ar = eg_rate_shift [SLOT->ar + SLOT->ksr ];
SLOT->eg_sel_ar = eg_rate_select[SLOT->ar + SLOT->ksr ];
}
else
{
SLOT->eg_sh_ar = 0;
SLOT->eg_sel_ar = 13*RATE_STEPS;
}
SLOT->dr = (v&0x0f)? 16 + ((v&0x0f)<<2) : 0;
SLOT->eg_sh_dr = eg_rate_shift [SLOT->dr + SLOT->ksr ];
SLOT->eg_sel_dr = eg_rate_select[SLOT->dr + SLOT->ksr ];
}
/* set sustain level & release rate */
INLINE void set_sl_rr(int slot,int v)
{
YM2413_OPLL_CH *CH = &ym2413.P_CH[slot/2];
YM2413_OPLL_SLOT *SLOT = &CH->SLOT[slot&1];
SLOT->sl = sl_tab[ v>>4 ];
SLOT->rr = (v&0x0f)? 16 + ((v&0x0f)<<2) : 0;
SLOT->eg_sh_rr = eg_rate_shift [SLOT->rr + SLOT->ksr ];
SLOT->eg_sel_rr = eg_rate_select[SLOT->rr + SLOT->ksr ];
}
static void load_instrument(UINT32 chan, UINT32 slot, UINT8* inst )
{
set_mul(slot, inst[0]);
set_mul(slot+1, inst[1]);
set_ksl_tl(chan, inst[2]);
set_ksl_wave_fb(chan, inst[3]);
set_ar_dr(slot, inst[4]);
set_ar_dr(slot+1, inst[5]);
set_sl_rr(slot, inst[6]);
set_sl_rr(slot+1, inst[7]);
}
static void update_instrument_zero(UINT8 r)
{
UINT8* inst = &ym2413.inst_tab[0][0]; /* point to user instrument */
UINT32 chan;
UINT32 chan_max = 9;
if (ym2413.rhythm & 0x20)
chan_max=6;
switch(r&7)
{
case 0:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_mul(chan*2, inst[0]);
}
}
break;
case 1:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_mul(chan*2+1, inst[1]);
}
}
break;
case 2:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_ksl_tl(chan, inst[2]);
}
}
break;
case 3:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_ksl_wave_fb(chan, inst[3]);
}
}
break;
case 4:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_ar_dr(chan*2, inst[4]);
}
}
break;
case 5:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_ar_dr(chan*2+1, inst[5]);
}
}
break;
case 6:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_sl_rr(chan*2, inst[6]);
}
}
break;
case 7:
for (chan=0; chan<chan_max; chan++)
{
if ((ym2413.instvol_r[chan]&0xf0)==0)
{
set_sl_rr(chan*2+1, inst[7]);
}
}
break;
}
}
/* write a value v to register r on chip chip */
static void OPLLWriteReg(int r, int v)
{
YM2413_OPLL_CH *CH;
YM2413_OPLL_SLOT *SLOT;
/* adjust bus to 8 bits */
r &= 0xff;
v &= 0xff;
switch(r&0xf0)
{
case 0x00: /* 00-0f:control */
{
switch(r&0x0f)
{
case 0x00: /* AM/VIB/EGTYP/KSR/MULTI (modulator) */
case 0x01: /* AM/VIB/EGTYP/KSR/MULTI (carrier) */
case 0x02: /* Key Scale Level, Total Level (modulator) */
case 0x03: /* Key Scale Level, carrier waveform, modulator waveform, Feedback */
case 0x04: /* Attack, Decay (modulator) */
case 0x05: /* Attack, Decay (carrier) */
case 0x06: /* Sustain, Release (modulator) */
case 0x07: /* Sustain, Release (carrier) */
{
ym2413.inst_tab[0][r] = v;
update_instrument_zero(r);
break;
}
case 0x0e: /* x, x, r,bd,sd,tom,tc,hh */
{
if(v&0x20)
{
/* rhythm OFF to ON */
if ((ym2413.rhythm&0x20)==0)
{
/* Load instrument settings for channel seven(chan=6 since we're zero based). (Bass drum) */
load_instrument(6, 12, &ym2413.inst_tab[16][0]);
/* Load instrument settings for channel eight. (High hat and snare drum) */
load_instrument(7, 14, &ym2413.inst_tab[17][0]);
CH = &ym2413.P_CH[7];
SLOT = &CH->SLOT[SLOT1]; /* modulator envelope is HH */
SLOT->TL = ((ym2413.instvol_r[7]>>4)<<2)<<(ENV_BITS-2-7); /* 7 bits TL (bit 6 = always 0) */
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
/* Load instrument settings for channel nine. (Tom-tom and top cymbal) */
load_instrument(8, 16, &ym2413.inst_tab[18][0]);
CH = &ym2413.P_CH[8];
SLOT = &CH->SLOT[SLOT1]; /* modulator envelope is TOM */
SLOT->TL = ((ym2413.instvol_r[8]>>4)<<2)<<(ENV_BITS-2-7); /* 7 bits TL (bit 6 = always 0) */
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
}
/* BD key on/off */
if(v&0x10)
{
KEY_ON (&ym2413.P_CH[6].SLOT[SLOT1], 2);
KEY_ON (&ym2413.P_CH[6].SLOT[SLOT2], 2);
}
else
{
KEY_OFF(&ym2413.P_CH[6].SLOT[SLOT1],~2);
KEY_OFF(&ym2413.P_CH[6].SLOT[SLOT2],~2);
}
/* HH key on/off */
if(v&0x01) KEY_ON (&ym2413.P_CH[7].SLOT[SLOT1], 2);
else KEY_OFF(&ym2413.P_CH[7].SLOT[SLOT1],~2);
/* SD key on/off */
if(v&0x08) KEY_ON (&ym2413.P_CH[7].SLOT[SLOT2], 2);
else KEY_OFF(&ym2413.P_CH[7].SLOT[SLOT2],~2);
/* TOM key on/off */
if(v&0x04) KEY_ON (&ym2413.P_CH[8].SLOT[SLOT1], 2);
else KEY_OFF(&ym2413.P_CH[8].SLOT[SLOT1],~2);
/* TOP-CY key on/off */
if(v&0x02) KEY_ON (&ym2413.P_CH[8].SLOT[SLOT2], 2);
else KEY_OFF(&ym2413.P_CH[8].SLOT[SLOT2],~2);
}
else
{
/* rhythm ON to OFF */
if (ym2413.rhythm&0x20)
{
/* Load instrument settings for channel seven(chan=6 since we're zero based).*/
load_instrument(6, 12, &ym2413.inst_tab[ym2413.instvol_r[6]>>4][0]);
/* Load instrument settings for channel eight.*/
load_instrument(7, 14, &ym2413.inst_tab[ym2413.instvol_r[7]>>4][0]);
/* Load instrument settings for channel nine.*/
load_instrument(8, 16, &ym2413.inst_tab[ym2413.instvol_r[8]>>4][0]);
}
/* BD key off */
KEY_OFF(&ym2413.P_CH[6].SLOT[SLOT1],~2);
KEY_OFF(&ym2413.P_CH[6].SLOT[SLOT2],~2);
/* HH key off */
KEY_OFF(&ym2413.P_CH[7].SLOT[SLOT1],~2);
/* SD key off */
KEY_OFF(&ym2413.P_CH[7].SLOT[SLOT2],~2);
/* TOM key off */
KEY_OFF(&ym2413.P_CH[8].SLOT[SLOT1],~2);
/* TOP-CY off */
KEY_OFF(&ym2413.P_CH[8].SLOT[SLOT2],~2);
}
ym2413.rhythm = v&0x3f;
break;
}
}
break;
}
case 0x10:
case 0x20:
{
int block_fnum;
int chan = r&0x0f;
if (chan >= 9)
chan -= 9; /* verified on real YM2413 */
CH = &ym2413.P_CH[chan];
if(r&0x10)
{
/* 10-18: FNUM 0-7 */
block_fnum = (CH->block_fnum&0x0f00) | v;
}
else
{
/* 20-28: suson, keyon, block, FNUM 8 */
block_fnum = ((v&0x0f)<<8) | (CH->block_fnum&0xff);
if(v&0x10)
{
KEY_ON (&CH->SLOT[SLOT1], 1);
KEY_ON (&CH->SLOT[SLOT2], 1);
}
else
{
KEY_OFF(&CH->SLOT[SLOT1],~1);
KEY_OFF(&CH->SLOT[SLOT2],~1);
}
CH->sus = v & 0x20;
}
/* update */
if(CH->block_fnum != block_fnum)
{
CH->block_fnum = block_fnum;
/* BLK 2,1,0 bits -> bits 3,2,1 of kcode, FNUM MSB -> kcode LSB */
CH->kcode = (block_fnum&0x0f00)>>8;
CH->ksl_base = ksl_tab[block_fnum>>5];
block_fnum = block_fnum * 2;
UINT8 block = (block_fnum&0x1c00) >> 10;
CH->fc = ym2413.fn_tab[block_fnum&0x03ff] >> (7-block);
/* refresh Total Level in both SLOTs of this channel */
CH->SLOT[SLOT1].TLL = CH->SLOT[SLOT1].TL + (CH->ksl_base>>CH->SLOT[SLOT1].ksl);
CH->SLOT[SLOT2].TLL = CH->SLOT[SLOT2].TL + (CH->ksl_base>>CH->SLOT[SLOT2].ksl);
/* refresh frequency counter in both SLOTs of this channel */
CALC_FCSLOT(CH,&CH->SLOT[SLOT1]);
CALC_FCSLOT(CH,&CH->SLOT[SLOT2]);
}
break;
}
case 0x30: /* inst 4 MSBs, VOL 4 LSBs */
{
int chan = r&0x0f;
if (chan >= 9)
chan -= 9; /* verified on real YM2413 */
CH = &ym2413.P_CH[chan];
SLOT = &CH->SLOT[SLOT2]; /* carrier */
SLOT->TL = ((v&0x0f)<<2)<<(ENV_BITS-2-7); /* 7 bits TL (bit 6 = always 0) */
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
/*check wether we are in rhythm mode and handle instrument/volume register accordingly*/
if ((chan>=6) && (ym2413.rhythm&0x20))
{
/* we're in rhythm mode*/
if (chan>=7) /* only for channel 7 and 8 (channel 6 is handled in usual way)*/
{
SLOT = &CH->SLOT[SLOT1]; /* modulator envelope is HH(chan=7) or TOM(chan=8) */
SLOT->TL = ((v>>4)<<2)<<(ENV_BITS-2-7); /* 7 bits TL (bit 6 = always 0) */
SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl);
}
}
else
{
if ((ym2413.instvol_r[chan]&0xf0) != (v&0xf0))
{
ym2413.instvol_r[chan] = v; /* store for later use */
load_instrument(chan, chan * 2, &ym2413.inst_tab[v>>4][0]);
}
}
break;
}
default:
break;
}
}
void YM2413Init(double clock, int rate)
{
init_tables();
/* clear */
memset(&ym2413,0,sizeof(YM2413));
ym2413.clock = clock;
ym2413.rate = rate;
/* init global tables */
OPLL_initalize();
}
void YM2413ResetChip(void)
{
int c,s;
int i;
ym2413.eg_timer = 0;
ym2413.eg_cnt = 0;
ym2413.noise_rng = 1; /* noise shift register */
/* setup instruments table */
for (i=0; i<19; i++)
{
for (c=0; c<8; c++)
{
ym2413.inst_tab[i][c] = table[i][c];
}
}
/* reset with register write */
OPLLWriteReg(0x0f,0); /*test reg*/
for(i = 0x3f ; i >= 0x10 ; i-- ) OPLLWriteReg(i,0x00);
/* reset operator parameters */
for( c = 0 ; c < 9 ; c++ )
{
YM2413_OPLL_CH *CH = &ym2413.P_CH[c];
for(s = 0 ; s < 2 ; s++ )
{
/* wave table */
CH->SLOT[s].wavetable = 0;
CH->SLOT[s].state = EG_OFF;
CH->SLOT[s].volume = MAX_ATT_INDEX;
}
}
}
/* YM2413 I/O interface */
void YM2413Write(unsigned int a, unsigned int v)
{
if( !(a&1) )
{
if( !(a&2) )
{
/* address port */
ym2413.address = v & 0xff;
}
else
{
/* status port */
ym2413.status = v & 0xff;
}
}
else
{
/* data port */
OPLLWriteReg(ym2413.address,v);
}
}
unsigned int YM2413Read(unsigned int a)
{
if( !(a&1) )
{
/* status port */
return ym2413.status;
}
return 0xff;
}
void YM2413Update(long int *buffer, int length)
{
int i, out;
for( i=0; i < length ; i++ )
{
output[0] = 0;
output[1] = 0;
advance_lfo();
/* FM part */
chan_calc(&ym2413.P_CH[0]);
chan_calc(&ym2413.P_CH[1]);
chan_calc(&ym2413.P_CH[2]);
chan_calc(&ym2413.P_CH[3]);
chan_calc(&ym2413.P_CH[4]);
chan_calc(&ym2413.P_CH[5]);
if(!(ym2413.rhythm&0x20))
{
chan_calc(&ym2413.P_CH[6]);
chan_calc(&ym2413.P_CH[7]);
chan_calc(&ym2413.P_CH[8]);
}
else /* Rhythm part */
{
rhythm_calc(&ym2413.P_CH[0], (ym2413.noise_rng>>0)&1 );
}
/* Melody (MO) & Rythm (RO) outputs mixing */
out = output[0] + (output[1] * 2);
/* Store to stereo sound buffer */
*buffer++ = out;
*buffer++ = out;
advance();
}
}
unsigned char *YM2413GetContextPtr(void)
{
return (unsigned char *)&ym2413;
}
unsigned int YM2413GetContextSize(void)
{
return sizeof(YM2413);
}
void YM2413Restore(unsigned char *buffer)
{
/* save current timings */
double clock = ym2413.clock;
int rate = ym2413.rate;
/* restore internal state */
memcpy(&ym2413, buffer, sizeof(YM2413));
/* keep current timings */
ym2413.clock = clock;
ym2413.rate = rate;
OPLL_initalize();
}
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