/* ** ** 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, cleaned code & added FM board interface for Genesis Plus GX **/ #include "shared.h" #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<>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 ] >> 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<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<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<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<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<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<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<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<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<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)>>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)>>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<>= 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; i0.0) 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]; } return 1; } static void OPLL_initalize(void) { int i; /* YM2413 always running at original frequency */ double 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<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]; SLOT->wavetable = ((v&0x10)>>4)*SIN_LEN; v >>= 6; /* 0 / 1.5 / 3.0 / 6.0 dB/OCT */ SLOT->ksl = v ? 3-v : 31; SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl); } /* 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; chanSLOT[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) { UINT8 block; 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; 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(void) { init_tables(); /* clear */ memset(&ym2413,0,sizeof(YM2413)); /* 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&2) ) { if( !(a&1) ) { /* address port */ ym2413.address = v & 0xff; } else { /* data port */ OPLLWriteReg(ym2413.address,v); } } else { /* latched bit (Master System specific) */ ym2413.status = v & 0x01; } } unsigned int YM2413Read(unsigned int a) { /* D0=latched bit, D1-D2 need to be zero (Master System specific) */ return 0xF8 | ym2413.status; } void YM2413Update(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 & amplification (latched bit controls FM output) */ out = (output[0] + (output[1] * 2)) * 2 * ym2413.status; /* 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); }