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Diffstat (limited to 'src/chips/mame/mame_fmopl.cpp')
| -rw-r--r-- | src/chips/mame/mame_fmopl.cpp | 1852 |
1 files changed, 1852 insertions, 0 deletions
diff --git a/src/chips/mame/mame_fmopl.cpp b/src/chips/mame/mame_fmopl.cpp new file mode 100644 index 0000000..c1dbada --- /dev/null +++ b/src/chips/mame/mame_fmopl.cpp @@ -0,0 +1,1852 @@ +// license:GPL-2.0+ +// copyright-holders:Jarek Burczynski,Tatsuyuki Satoh +/* + +This file is based on fmopl.c from MAME. The non-YM3816 parts have been +ripped out in the interest of making this simpler, since Doom music doesn't +need them. I also made it render the sound a voice at a time instead of a +sample at a time, so unused voices don't waste time being calculated. If all +voices are playing, it's not much difference, but it does offer a big +improvement when only a few voices are playing. + + + +** +** File: fmopl.c - software implementation of FM sound generator +** types OPL and OPL2 +** +** Copyright Jarek Burczynski (bujar at mame dot net) +** Copyright Tatsuyuki Satoh , MultiArcadeMachineEmulator development +** +** Version 0.72 +** + +Revision History: + +04-08-2003 Jarek Burczynski: + - removed BFRDY hack. BFRDY is busy flag, and it should be 0 only when the chip + handles memory read/write or during the adpcm synthesis when the chip + requests another byte of ADPCM data. + +24-07-2003 Jarek Burczynski: + - added a small hack for Y8950 status BFRDY flag (bit 3 should be set after + some (unknown) delay). Right now it's always set. + +14-06-2003 Jarek Burczynski: + - implemented all of the status register flags in Y8950 emulation + - renamed y8950_set_delta_t_memory() parameters from _rom_ to _mem_ since + they can be either RAM or ROM + +08-10-2002 Jarek Burczynski (thanks to Dox for the YM3526 chip) + - corrected ym3526_read() to always set bit 2 and bit 1 + to HIGH state - identical to ym3812_read (verified on real YM3526) + +04-28-2002 Jarek Burczynski: + - binary exact Envelope Generator (verified on real YM3812); + compared to YM2151: the EG clock is equal to internal_clock, + rates are 2 times slower and volume resolution is one bit less + - modified interface functions (they no longer return pointer - + that's internal to the emulator now): + - new wrapper functions for OPLCreate: ym3526_init(), ym3812_init() and y8950_init() + - corrected 'off by one' error in feedback calculations (when feedback is off) + - enabled waveform usage (credit goes to Vlad Romascanu and zazzal22) + - speeded up noise generator calculations (Nicola Salmoria) + +03-24-2002 Jarek Burczynski (thanks to Dox for the YM3812 chip) + Complete rewrite (all verified on real YM3812): + - corrected sin_tab and tl_tab data + - corrected operator output calculations + - corrected waveform_select_enable register; + simply: ignore all writes to waveform_select register when + waveform_select_enable == 0 and do not change the waveform previously selected. + - corrected KSR handling + - corrected Envelope Generator: attack shape, Sustain mode and + Percussive/Non-percussive modes handling + - Envelope Generator rates are two times slower now + - LFO amplitude (tremolo) and phase modulation (vibrato) + - rhythm sounds phase generation + - white noise generator (big thanks to Olivier Galibert for mentioning Berlekamp-Massey algorithm) + - corrected key on/off handling (the 'key' signal is ORed from three sources: FM, rhythm and CSM) + - funky details (like ignoring output of operator 1 in BD rhythm sound when connect == 1) + +12-28-2001 Acho A. Tang + - reflected Delta-T EOS status on Y8950 status port. + - fixed subscription range of attack/decay tables + + + To do: + add delay before key off in CSM mode (see CSMKeyControll) + verify volume of the FM part on the Y8950 +*/ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <math.h> +#include <stdint.h> +#include <string> +//#include "driver.h" /* use M.A.M.E. */ +#include "opl.h" + +/* compiler dependence */ +#ifndef OSD_CPU_H +#define OSD_CPU_H +#endif + +#ifndef PI +#define PI 3.14159265358979323846 +#endif + +#ifdef _MSC_VER +#pragma warning (disable: 4244) +#endif + + +#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 TIMER_SH 16 /* 16.16 fixed point (timers 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-1))-1) /*511*/ +#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_ATT 4 +#define EG_DEC 3 +#define EG_SUS 2 +#define EG_REL 1 +#define EG_OFF 0 + + +#define OPL_CLOCK 3579545 // master clock (Hz) +#define OPL_RATE 49716 // sampling rate (Hz) +#define OPL_TIMERBASE (OPL_CLOCK / 72.0) // Timer base time (==sampling time) +#define OPL_FREQBASE (OPL_TIMERBASE / OPL_RATE) // frequency base + + +/* Saving is necessary for member of the 'R' mark for suspend/resume */ + +struct OPL_SLOT +{ + uint32_t ar; /* attack rate: AR<<2 */ + uint32_t dr; /* decay rate: DR<<2 */ + uint32_t rr; /* release rate:RR<<2 */ + uint8_t KSR; /* key scale rate */ + uint8_t ksl; /* keyscale level */ + uint8_t ksr; /* key scale rate: kcode>>KSR */ + uint8_t mul; /* multiple: mul_tab[ML] */ + + /* Phase Generator */ + uint32_t Cnt; /* frequency counter */ + uint32_t Incr; /* frequency counter step */ + uint8_t FB; /* feedback shift value */ + int32_t *connect1; /* slot1 output pointer */ + int32_t op1_out[2]; /* slot1 output for feedback */ + uint8_t CON; /* connection (algorithm) type */ + + /* Envelope Generator */ + uint8_t eg_type; /* percussive/non-percussive mode */ + uint8_t state; /* phase type */ + uint32_t TL; /* total level: TL << 2 */ + int32_t TLL; /* adjusted now TL */ + int32_t volume; /* envelope counter */ + uint32_t sl; /* sustain level: sl_tab[SL] */ + uint8_t eg_sh_ar; /* (attack state) */ + uint8_t eg_sel_ar; /* (attack state) */ + uint8_t eg_sh_dr; /* (decay state) */ + uint8_t eg_sel_dr; /* (decay state) */ + uint8_t eg_sh_rr; /* (release state) */ + uint8_t eg_sel_rr; /* (release state) */ + uint32_t key; /* 0 = KEY OFF, >0 = KEY ON */ + + /* LFO */ + uint32_t AMmask; /* LFO Amplitude Modulation enable mask */ + uint8_t vib; /* LFO Phase Modulation enable flag (active high)*/ + + /* waveform select */ + uint16_t wavetable; +}; + +struct OPL_CH +{ + OPL_SLOT SLOT[2]; + /* phase generator state */ + uint32_t block_fnum; /* block+fnum */ + uint32_t fc; /* Freq. Increment base */ + uint32_t ksl_base; /* KeyScaleLevel Base step */ + uint8_t kcode; /* key code (for key scaling) */ + float LeftVol; /* volumes for stereo panning */ + float RightVol; +}; + +/* OPL state */ +struct FM_OPL +{ + /* FM channel slots */ + OPL_CH P_CH[9]; /* OPL/OPL2 chips have 9 channels*/ + + uint32_t eg_cnt; /* global envelope generator counter */ + uint32_t eg_timer; /* global envelope generator counter works at frequency = chipclock/72 */ + uint32_t eg_timer_add; /* step of eg_timer */ + uint32_t eg_timer_overflow; /* envelope generator timer overflows every 1 sample (on real chip) */ + + uint8_t rhythm; /* Rhythm mode */ + + uint32_t fn_tab[1024]; /* fnumber->increment counter */ + + /* LFO */ + + uint8_t lfo_am_depth; + uint8_t lfo_pm_depth_range; + uint32_t lfo_am_cnt; + uint32_t lfo_am_inc; + uint32_t lfo_pm_cnt; + uint32_t lfo_pm_inc; + + uint32_t noise_rng; /* 23 bit noise shift register */ + uint32_t noise_p; /* current noise 'phase' */ + uint32_t noise_f; /* current noise period */ + + uint8_t wavesel; /* waveform select enable flag */ + + int T[2]; /* timer counters */ + uint8_t st[2]; /* timer enable */ + + + uint8_t address; /* address register */ + uint8_t status; /* status flag */ + uint8_t statusmask; /* status mask */ + uint8_t mode; /* Reg.08 : CSM,notesel,etc. */ + + bool IsStereo; /* Write stereo output */ +}; + + + +/* mapping of register number (offset) to slot number used by the emulator */ +static const int slot_array[32]= +{ + 0, 2, 4, 1, 3, 5,-1,-1, + 6, 8,10, 7, 9,11,-1,-1, + 12,14,16,13,15,17,-1,-1, + -1,-1,-1,-1,-1,-1,-1,-1 +}; + +/* 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 (0.1875/2.0) +static const uint32_t ksl_tab[8*16]= +{ + /* OCT 0 */ + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + /* OCT 1 */ + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + uint32_t(0.000/DV), uint32_t(0.750/DV), uint32_t(1.125/DV), uint32_t(1.500/DV), + uint32_t(1.875/DV), uint32_t(2.250/DV), uint32_t(2.625/DV), uint32_t(3.000/DV), + /* OCT 2 */ + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), + uint32_t(0.000/DV), uint32_t(1.125/DV), uint32_t(1.875/DV), uint32_t(2.625/DV), + uint32_t(3.000/DV), uint32_t(3.750/DV), uint32_t(4.125/DV), uint32_t(4.500/DV), + uint32_t(4.875/DV), uint32_t(5.250/DV), uint32_t(5.625/DV), uint32_t(6.000/DV), + /* OCT 3 */ + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(1.875/DV), + uint32_t(3.000/DV), uint32_t(4.125/DV), uint32_t(4.875/DV), uint32_t(5.625/DV), + uint32_t(6.000/DV), uint32_t(6.750/DV), uint32_t(7.125/DV), uint32_t(7.500/DV), + uint32_t(7.875/DV), uint32_t(8.250/DV), uint32_t(8.625/DV), uint32_t(9.000/DV), + /* OCT 4 */ + uint32_t(0.000/DV), uint32_t(0.000/DV), uint32_t(3.000/DV), uint32_t(4.875/DV), + uint32_t(6.000/DV), uint32_t(7.125/DV), uint32_t(7.875/DV), uint32_t(8.625/DV), + uint32_t(9.000/DV), uint32_t(9.750/DV),uint32_t(10.125/DV),uint32_t(10.500/DV), + uint32_t(10.875/DV),uint32_t(11.250/DV),uint32_t(11.625/DV),uint32_t(12.000/DV), + /* OCT 5 */ + uint32_t(0.000/DV), uint32_t(3.000/DV), uint32_t(6.000/DV), uint32_t(7.875/DV), + uint32_t(9.000/DV),uint32_t(10.125/DV),uint32_t(10.875/DV),uint32_t(11.625/DV), + uint32_t(12.000/DV),uint32_t(12.750/DV),uint32_t(13.125/DV),uint32_t(13.500/DV), + uint32_t(13.875/DV),uint32_t(14.250/DV),uint32_t(14.625/DV),uint32_t(15.000/DV), + /* OCT 6 */ + uint32_t(0.000/DV), uint32_t(6.000/DV), uint32_t(9.000/DV),uint32_t(10.875/DV), + uint32_t(12.000/DV),uint32_t(13.125/DV),uint32_t(13.875/DV),uint32_t(14.625/DV), + uint32_t(15.000/DV),uint32_t(15.750/DV),uint32_t(16.125/DV),uint32_t(16.500/DV), + uint32_t(16.875/DV),uint32_t(17.250/DV),uint32_t(17.625/DV),uint32_t(18.000/DV), + /* OCT 7 */ + uint32_t(0.000/DV), uint32_t(9.000/DV),uint32_t(12.000/DV),uint32_t(13.875/DV), + uint32_t(15.000/DV),uint32_t(16.125/DV),uint32_t(16.875/DV),uint32_t(17.625/DV), + uint32_t(18.000/DV),uint32_t(18.750/DV),uint32_t(19.125/DV),uint32_t(19.500/DV), + uint32_t(19.875/DV),uint32_t(20.250/DV),uint32_t(20.625/DV),uint32_t(21.000/DV) +}; +#undef DV + +/* 0 / 3.0 / 1.5 / 6.0 dB/OCT */ +static const uint32_t ksl_shift[4] = { 31, 1, 2, 0 }; + + +/* sustain level table (3dB per step) */ +/* 0 - 15: 0, 3, 6, 9,12,15,18,21,24,27,30,33,36,39,42,93 (dB)*/ +#define SC(db) (uint32_t) ( db * (2.0/ENV_STEP) ) +static const uint32_t 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(31) +}; +#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 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 0, 0 */ +/*mask 4095, 2047, 1023, 511, 255, 127, 63, 31, 15, 7, 3, 1, 0, 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(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), +O( 0),O( 0),O( 0),O( 0), + +/* 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_t mul_tab[16]= { +/* 1/2, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,10,12,12,15,15 */ + uint8_t(0.50*ML), uint8_t(1.00*ML), uint8_t(2.00*ML), uint8_t(3.00*ML), uint8_t(4.00*ML), uint8_t(5.00*ML), uint8_t(6.00*ML), uint8_t(7.00*ML), + uint8_t(8.00*ML), uint8_t(9.00*ML),uint8_t(10.00*ML),uint8_t(10.00*ML),uint8_t(12.00*ML),uint8_t(12.00*ML),uint8_t(15.00*ML),uint8_t(15.00*ML) +}; +#undef ML + +/* TL_TAB_LEN is calculated as: +* 12 - sinus amplitude bits (Y axis) +* 2 - sinus sign bit (Y axis) +* TL_RES_LEN - sinus resolution (X axis) +*/ +#define TL_TAB_LEN (12*2*TL_RES_LEN) +static signed int tl_tab[TL_TAB_LEN]; + +#define ENV_QUIET (TL_TAB_LEN>>4) + +/* sin waveform table in 'decibel' scale */ +/* four waveforms on OPL2 type chips */ +static unsigned int sin_tab[SIN_LEN * 4]; + + +/* 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. + + When AM = 1 data is used directly + When AM = 0 data is divided by 4 before being used (losing precision is important) +*/ + +#define LFO_AM_TAB_ELEMENTS 210 + +static const uint8_t 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 YM3812) */ +static const int8_t lfo_pm_table[8*8*2] = { +/* FNUM2/FNUM = 00 0xxxxxxx (0x0000) */ +0, 0, 0, 0, 0, 0, 0, 0, /*LFO PM depth = 0*/ +0, 0, 0, 0, 0, 0, 0, 0, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 00 1xxxxxxx (0x0080) */ +0, 0, 0, 0, 0, 0, 0, 0, /*LFO PM depth = 0*/ +1, 0, 0, 0,-1, 0, 0, 0, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 01 0xxxxxxx (0x0100) */ +1, 0, 0, 0,-1, 0, 0, 0, /*LFO PM depth = 0*/ +2, 1, 0,-1,-2,-1, 0, 1, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 01 1xxxxxxx (0x0180) */ +1, 0, 0, 0,-1, 0, 0, 0, /*LFO PM depth = 0*/ +3, 1, 0,-1,-3,-1, 0, 1, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 10 0xxxxxxx (0x0200) */ +2, 1, 0,-1,-2,-1, 0, 1, /*LFO PM depth = 0*/ +4, 2, 0,-2,-4,-2, 0, 2, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 10 1xxxxxxx (0x0280) */ +2, 1, 0,-1,-2,-1, 0, 1, /*LFO PM depth = 0*/ +5, 2, 0,-2,-5,-2, 0, 2, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 11 0xxxxxxx (0x0300) */ +3, 1, 0,-1,-3,-1, 0, 1, /*LFO PM depth = 0*/ +6, 3, 0,-3,-6,-3, 0, 3, /*LFO PM depth = 1*/ + +/* FNUM2/FNUM = 11 1xxxxxxx (0x0380) */ +3, 1, 0,-1,-3,-1, 0, 1, /*LFO PM depth = 0*/ +7, 3, 0,-3,-7,-3, 0, 3 /*LFO PM depth = 1*/ +}; + + + +/* work table */ +struct FM_WorkTable +{ + signed int phase_modulation; /* phase modulation input (SLOT 2) */ + signed int output; + + uint32_t LFO_AM; + int32_t LFO_PM; +}; + +static bool CalcVoice (FM_WorkTable *wt, FM_OPL *OPL, int voice, float *buffer, int length); +static bool CalcVoice (FM_WorkTable *wt, FM_OPL *OPL, int voice, short *buffer, int length); +static bool CalcRhythm (FM_WorkTable *wt, FM_OPL *OPL, float *buffer, int length); +static bool CalcRhythm (FM_WorkTable *wt, FM_OPL *OPL, short *buffer, int length); + + + +/* status set and IRQ handling */ +static inline void OPL_STATUS_SET(FM_OPL *OPL,int flag) +{ + /* set status flag */ + OPL->status |= flag; + if(!(OPL->status & 0x80)) + { + if(OPL->status & OPL->statusmask) + { /* IRQ on */ + OPL->status |= 0x80; + } + } +} + +/* status reset and IRQ handling */ +static inline void OPL_STATUS_RESET(FM_OPL *OPL,int flag) +{ + /* reset status flag */ + OPL->status &=~flag; + if((OPL->status & 0x80)) + { + if (!(OPL->status & OPL->statusmask) ) + { + OPL->status &= 0x7f; + } + } +} + +/* IRQ mask set */ +static inline void OPL_STATUSMASK_SET(FM_OPL *OPL,int flag) +{ + OPL->statusmask = flag; + /* IRQ handling check */ + OPL_STATUS_SET(OPL,0); + OPL_STATUS_RESET(OPL,0); +} + + +/* advance LFO to next sample */ +static inline void advance_lfo(FM_WorkTable *wt, FM_OPL *OPL) +{ + uint8_t tmp; + + /* LFO */ + OPL->lfo_am_cnt += OPL->lfo_am_inc; + if (OPL->lfo_am_cnt >= (uint32_t)(LFO_AM_TAB_ELEMENTS<<LFO_SH) ) /* lfo_am_table is 210 elements long */ + OPL->lfo_am_cnt -= (LFO_AM_TAB_ELEMENTS<<LFO_SH); + + tmp = lfo_am_table[ OPL->lfo_am_cnt >> LFO_SH ]; + + if (OPL->lfo_am_depth) + wt->LFO_AM = tmp; + else + wt->LFO_AM = tmp>>2; + + OPL->lfo_pm_cnt += OPL->lfo_pm_inc; + wt->LFO_PM = ((OPL->lfo_pm_cnt>>LFO_SH) & 7) | OPL->lfo_pm_depth_range; +} + +/* advance to next sample */ +static inline void advance(FM_WorkTable *wt, FM_OPL *OPL, int loch, int hich) +{ + OPL_CH *CH; + OPL_SLOT *op; + int i; + + OPL->eg_timer += OPL->eg_timer_add; + loch *= 2; + hich *= 2; + + while (OPL->eg_timer >= OPL->eg_timer_overflow) + { + OPL->eg_timer -= OPL->eg_timer_overflow; + + OPL->eg_cnt++; + + for (i = loch; i <= hich + 1; i++) + { + CH = &OPL->P_CH[i/2]; + op = &CH->SLOT[i&1]; + + /* Envelope Generator */ + switch(op->state) + { + case EG_ATT: /* attack phase */ + if ( !(OPL->eg_cnt & ((1<<op->eg_sh_ar)-1) ) ) + { + op->volume += (~op->volume * + (eg_inc[op->eg_sel_ar + ((OPL->eg_cnt>>op->eg_sh_ar)&7)]) + ) >>3; + + if (op->volume <= MIN_ATT_INDEX) + { + op->volume = MIN_ATT_INDEX; + op->state = EG_DEC; + } + + } + break; + + case EG_DEC: /* decay phase */ + if ( !(OPL->eg_cnt & ((1<<op->eg_sh_dr)-1) ) ) + { + op->volume += eg_inc[op->eg_sel_dr + ((OPL->eg_cnt>>op->eg_sh_dr)&7)]; + + if ( op->volume >= (int32_t)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 */ + { + /* do nothing */ + } + else /* percussive mode */ + { + /* during sustain phase chip adds Release Rate (in percussive mode) */ + if ( !(OPL->eg_cnt & ((1<<op->eg_sh_rr)-1) ) ) + { + op->volume += eg_inc[op->eg_sel_rr + ((OPL->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 */ + if ( !(OPL->eg_cnt & ((1<<op->eg_sh_rr)-1) ) ) + { + op->volume += eg_inc[op->eg_sel_rr + ((OPL->eg_cnt>>op->eg_sh_rr)&7)]; + + if ( op->volume >= MAX_ATT_INDEX ) + { + op->volume = MAX_ATT_INDEX; + op->state = EG_OFF; + } + + } + break; + + default: + break; + } + + /* Phase Generator */ + if(op->vib) + { + uint8_t block; + unsigned int block_fnum = CH->block_fnum; + + unsigned int fnum_lfo = (block_fnum&0x0380) >> 7; + + signed int lfo_fn_table_index_offset = lfo_pm_table[wt->LFO_PM + 16*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->Cnt += (OPL->fn_tab[block_fnum&0x03ff] >> (7-block)) * op->mul; + } + else /* LFO phase modulation = zero */ + { + op->Cnt += op->Incr; + } + } + else /* LFO phase modulation disabled for this operator */ + { + op->Cnt += op->Incr; + } + } + } +} + +static inline void advance_noise(FM_OPL *OPL) +{ + int i; + + /* 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. + */ + + OPL->noise_p += OPL->noise_f; + i = OPL->noise_p >> FREQ_SH; /* number of events (shifts of the shift register) */ + OPL->noise_p &= FREQ_MASK; + while (i) + { + /* + uint32_t j; + j = ( (OPL->noise_rng) ^ (OPL->noise_rng>>14) ^ (OPL->noise_rng>>15) ^ (OPL->noise_rng>>22) ) & 1; + OPL->noise_rng = (j<<22) | (OPL->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 (OPL->noise_rng & 1) OPL->noise_rng ^= 0x800302; + OPL->noise_rng >>= 1; + + i--; + } +} + + +static inline signed int op_calc(uint32_t phase, unsigned int env, signed int pm, unsigned int wave_tab) +{ + uint32_t p; + + p = (env<<4) + sin_tab[wave_tab + ((((signed int)((phase & ~FREQ_MASK) + (pm<<16))) >> FREQ_SH ) & SIN_MASK) ]; + + if (p >= TL_TAB_LEN) + return 0; + return tl_tab[p]; +} + +static inline signed int op_calc1(uint32_t phase, unsigned int env, signed int pm, unsigned int wave_tab) +{ + uint32_t p; + + p = (env<<4) + 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_t)(OP)->volume) + (wt->LFO_AM & (OP)->AMmask)) + +/* calculate output */ +static inline float OPL_CALC_CH( FM_WorkTable *wt, OPL_CH *CH ) +{ + OPL_SLOT *SLOT; + unsigned int env; + signed int out; + + wt->phase_modulation = 0; + + /* 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]; + *SLOT->connect1 += SLOT->op1_out[0]; + SLOT->op1_out[1] = 0; + if( env < ENV_QUIET ) + { + if (!SLOT->FB) + out = 0; + SLOT->op1_out[1] = op_calc1(SLOT->Cnt, env, (out<<SLOT->FB), SLOT->wavetable ); + } + + /* SLOT 2 */ + SLOT++; + env = volume_calc(SLOT); + if( env < ENV_QUIET ) + { + wt->output += op_calc(SLOT->Cnt, env, wt->phase_modulation, SLOT->wavetable); + /* [RH] Convert to floating point. */ + return float(wt->output) / 10240; + } + return 0; +} + +static inline short OPL_CALC_CH_S( FM_WorkTable *wt, OPL_CH *CH ) +{ + OPL_SLOT *SLOT; + unsigned int env; + signed int out; + + wt->phase_modulation = 0; + + /* 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]; + *SLOT->connect1 += SLOT->op1_out[0]; + SLOT->op1_out[1] = 0; + if( env < ENV_QUIET ) + { + if (!SLOT->FB) + out = 0; + SLOT->op1_out[1] = op_calc1(SLOT->Cnt, env, (out<<SLOT->FB), SLOT->wavetable ); + } + + /* SLOT 2 */ + SLOT++; + env = volume_calc(SLOT); + if( env < ENV_QUIET ) + { + wt->output += op_calc(SLOT->Cnt, env, wt->phase_modulation, SLOT->wavetable); + return wt->output; + } + return 0; +} + +/* + 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 */ + +static inline void OPL_CALC_RH( FM_WorkTable *wt, OPL_CH *CH, unsigned int noise ) +{ + OPL_SLOT *SLOT; + signed int out; + unsigned int env; + + + /* 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 + */ + + wt->phase_modulation = 0; + /* 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]; + + if (!SLOT->CON) + wt->phase_modulation = SLOT->op1_out[0]; + /* else ignore output of operator 1 */ + + SLOT->op1_out[1] = 0; + if( env < ENV_QUIET ) + { + if (!SLOT->FB) + out = 0; + SLOT->op1_out[1] = op_calc1(SLOT->Cnt, env, (out<<SLOT->FB), SLOT->wavetable ); + } + + /* SLOT 2 */ + SLOT++; + env = volume_calc(SLOT); + if( env < ENV_QUIET ) + wt->output += op_calc(SLOT->Cnt, env, wt->phase_modulation, SLOT->wavetable) * 2; + + + /* 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].Cnt>>FREQ_SH)>>7)&1; + unsigned char bit3 = ((CH[7].SLOT[SLOT1].Cnt>>FREQ_SH)>>3)&1; + unsigned char bit2 = ((CH[7].SLOT[SLOT1].Cnt>>FREQ_SH)>>2)&1; + + unsigned char res1 = (bit2 ^ bit7) | bit3; + + /* when res1 = 0 phase = 0x000 | 0xd0; */ + /* when res1 = 1 phase = 0x200 | (0xd0>>2); */ + uint32_t phase = res1 ? (0x200|(0xd0>>2)) : 0xd0; + + /* enable gate based on frequency of operator 2 in channel 8 */ + unsigned char bit5e= ((CH[8].SLOT[SLOT2].Cnt>>FREQ_SH)>>5)&1; + unsigned char bit3e= ((CH[8].SLOT[SLOT2].Cnt>>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; + } + + wt->output += op_calc(phase<<FREQ_SH, env, 0, CH[7].SLOT[SLOT1].wavetable) * 2; + } + + /* 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].Cnt>>FREQ_SH)>>8)&1; + + /* when bit8 = 0 phase = 0x100; */ + /* when bit8 = 1 phase = 0x200; */ + uint32_t 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; + + wt->output += op_calc(phase<<FREQ_SH, env, 0, CH[7].SLOT[SLOT2].wavetable) * 2; + } + + /* Tom Tom (verified on real YM3812) */ + env = volume_calc(&CH[8].SLOT[SLOT1]); + if( env < ENV_QUIET ) + wt->output += op_calc(CH[8].SLOT[SLOT1].Cnt, env, 0, CH[8].SLOT[SLOT2].wavetable) * 2; + + /* Top Cymbal (verified on real YM3812) */ + 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].Cnt>>FREQ_SH)>>7)&1; + unsigned char bit3 = ((CH[7].SLOT[SLOT1].Cnt>>FREQ_SH)>>3)&1; + unsigned char bit2 = ((CH[7].SLOT[SLOT1].Cnt>>FREQ_SH)>>2)&1; + + unsigned char res1 = (bit2 ^ bit7) | bit3; + + /* when res1 = 0 phase = 0x000 | 0x100; */ + /* when res1 = 1 phase = 0x200 | 0x100; */ + uint32_t phase = res1 ? 0x300 : 0x100; + + /* enable gate based on frequency of operator 2 in channel 8 */ + unsigned char bit5e= ((CH[8].SLOT[SLOT2].Cnt>>FREQ_SH)>>5)&1; + unsigned char bit3e= ((CH[8].SLOT[SLOT2].Cnt>>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; + + wt->output += op_calc(phase<<FREQ_SH, env, 0, CH[8].SLOT[SLOT2].wavetable) * 2; + } +} + + +/* generic table initialize */ +static void init_tables(void) +{ + signed int i,x; + signed int n; + double o,m; + + /* We only need to do this once. */ + static bool did_init = false; + + if (did_init) + { + return; + } + + for (x=0; x<TL_RES_LEN; x++) + { + m = (1<<16) / pow(2.0, (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 */ + n = (n+1)>>1; /* round to nearest */ + /* 11 bits here (rounded) */ + n <<= 1; /* 12 bits here (as in real chip) */ + tl_tab[ x*2 + 0 ] = n; + tl_tab[ x*2 + 1 ] = -tl_tab[ x*2 + 0 ]; + + for (i=1; i<12; 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; + } + } + + for (i=0; i<SIN_LEN; i++) + { + /* non-standard sinus */ + m = sin( ((i*2)+1) * 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(2.0); /* convert to 'decibels' */ + else + o = 8*log(-1.0/m)/log(2.0); /* 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; + + sin_tab[ i ] = n*2 + (m>=0.0? 0: 1 ); + } + + for (i=0; i<SIN_LEN; i++) + { + /* 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]; + + /* waveform 2: __ __ __ __ */ + /* / \/ \/ \/ \*/ + /* abs(sin) */ + + sin_tab[2*SIN_LEN+i] = sin_tab[i & (SIN_MASK>>1) ]; + + /* waveform 3: _ _ _ _ */ + /* / |_/ |_/ |_/ |_*/ + /* abs(output only first quarter of the sinus waveform) */ + + if (i & (1<<(SIN_BITS-2)) ) + sin_tab[3*SIN_LEN+i] = TL_TAB_LEN; + else + sin_tab[3*SIN_LEN+i] = sin_tab[i & (SIN_MASK>>2)]; + } + + did_init = true; +} + +static void OPL_initalize(FM_OPL *OPL) +{ + int i; + + /* make fnumber -> increment counter table */ + for( i=0 ; i < 1024 ; i++ ) + { + /* opn phase increment counter = 20bit */ + OPL->fn_tab[i] = (uint32_t)( (double)i * 64 * OPL_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 */ + OPL->lfo_am_inc = uint32_t((1.0 / 64.0 ) * (1<<LFO_SH) * OPL_FREQBASE); + + /* Vibrato: 8 output levels (triangle waveform); 1 level takes 1024 samples */ + OPL->lfo_pm_inc = uint32_t((1.0 / 1024.0) * (1<<LFO_SH) * OPL_FREQBASE); + + OPL->eg_timer_add = uint32_t((1<<EG_SH) * OPL_FREQBASE); + OPL->eg_timer_overflow = uint32_t(( 1 ) * (1<<EG_SH)); + + // [RH] Support full MIDI panning. (But default to mono and center panning.) + OPL->IsStereo = false; + for (int i = 0; i < 9; ++i) + { + OPL->P_CH[i].LeftVol = (float)CENTER_PANNING_POWER; + OPL->P_CH[i].RightVol = (float)CENTER_PANNING_POWER; + } +} + +static inline void FM_KEYON(OPL_SLOT *SLOT, uint32_t key_set) +{ + if( !SLOT->key ) + { + /* restart Phase Generator */ + SLOT->Cnt = 0; + /* phase -> Attack */ + SLOT->state = EG_ATT; + } + SLOT->key |= key_set; +} + +static inline void FM_KEYOFF(OPL_SLOT *SLOT, uint32_t 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) */ +static inline void CALC_FCSLOT(OPL_CH *CH,OPL_SLOT *SLOT) +{ + int ksr; + + /* (frequency) phase increment counter */ + SLOT->Incr = 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 ]; + } +} + +/* set multi,am,vib,EG-TYP,KSR,mul */ +static inline void set_mul(FM_OPL *OPL,int slot,int v) +{ + OPL_CH *CH = &OPL->P_CH[slot/2]; + OPL_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 */ +static inline void set_ksl_tl(FM_OPL *OPL,int slot,int v) +{ + OPL_CH *CH = &OPL->P_CH[slot/2]; + OPL_SLOT *SLOT = &CH->SLOT[slot&1]; + + SLOT->ksl = ksl_shift[v >> 6]; + SLOT->TL = (v&0x3f)<<(ENV_BITS-1-7); /* 7 bits TL (bit 6 = always 0) */ + + SLOT->TLL = SLOT->TL + (CH->ksl_base>>SLOT->ksl); +} + +/* set attack rate & decay rate */ +static inline void set_ar_dr(FM_OPL *OPL,int slot,int v) +{ + OPL_CH *CH = &OPL->P_CH[slot/2]; + OPL_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 */ +static inline void set_sl_rr(FM_OPL *OPL,int slot,int v) +{ + OPL_CH *CH = &OPL->P_CH[slot/2]; + OPL_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 ]; +} + + +/* write a value v to register r on OPL chip */ +static void WriteRegister(FM_WorkTable *wt, FM_OPL *OPL, int r, int v) +{ + OPL_CH *CH; + int slot; + int block_fnum; + + /* adjust bus to 8 bits */ + r &= 0xff; + v &= 0xff; + + switch(r&0xe0) + { + case 0x00: /* 00-1f:control */ + switch(r&0x1f) + { + case 0x01: /* waveform select enable */ + OPL->wavesel = v&0x20; + break; + case 0x02: /* Timer 1 */ + OPL->T[0] = (256-v)*4; + break; + case 0x03: /* Timer 2 */ + OPL->T[1] = (256-v)*16; + break; + case 0x04: /* IRQ clear / mask and Timer enable */ + if(v&0x80) + { /* IRQ flag clear */ + OPL_STATUS_RESET(OPL,0x7f-0x08); /* don't reset BFRDY flag or we will have to call deltat module to set the flag */ + } + else + { /* set IRQ mask ,timer enable*/ + uint8_t st1 = v&1; + uint8_t st2 = (v>>1)&1; + + /* IRQRST,T1MSK,t2MSK,EOSMSK,BRMSK,x,ST2,ST1 */ + OPL_STATUS_RESET(OPL, v & (0x78-0x08) ); + OPL_STATUSMASK_SET(OPL, (~v) & 0x78 ); + + /* timer 2 */ + if(OPL->st[1] != st2) + { + OPL->st[1] = st2; + } + /* timer 1 */ + if(OPL->st[0] != st1) + { + OPL->st[0] = st1; + } + } + break; + case 0x08: /* MODE,DELTA-T control 2 : CSM,NOTESEL,x,x,smpl,da/ad,64k,rom */ + OPL->mode = v; + break; + } + break; + case 0x20: /* am ON, vib ON, ksr, eg_type, mul */ + slot = slot_array[r&0x1f]; + if(slot < 0) return; + set_mul(OPL,slot,v); + break; + case 0x40: + slot = slot_array[r&0x1f]; + if(slot < 0) return; + set_ksl_tl(OPL,slot,v); + break; + case 0x60: + slot = slot_array[r&0x1f]; + if(slot < 0) return; + set_ar_dr(OPL,slot,v); + break; + case 0x80: + slot = slot_array[r&0x1f]; + if(slot < 0) return; + set_sl_rr(OPL,slot,v); + break; + case 0xa0: + if (r == 0xbd) /* am depth, vibrato depth, r,bd,sd,tom,tc,hh */ + { + OPL->lfo_am_depth = v & 0x80; + OPL->lfo_pm_depth_range = (v&0x40) ? 8 : 0; + + OPL->rhythm = v&0x3f; + + if(OPL->rhythm&0x20) + { + /* BD key on/off */ + if(v&0x10) + { + FM_KEYON (&OPL->P_CH[6].SLOT[SLOT1], 2); + FM_KEYON (&OPL->P_CH[6].SLOT[SLOT2], 2); + } + else + { + FM_KEYOFF(&OPL->P_CH[6].SLOT[SLOT1],~2); + FM_KEYOFF(&OPL->P_CH[6].SLOT[SLOT2],~2); + } + /* HH key on/off */ + if(v&0x01) FM_KEYON (&OPL->P_CH[7].SLOT[SLOT1], 2); + else FM_KEYOFF(&OPL->P_CH[7].SLOT[SLOT1],~2); + /* SD key on/off */ + if(v&0x08) FM_KEYON (&OPL->P_CH[7].SLOT[SLOT2], 2); + else FM_KEYOFF(&OPL->P_CH[7].SLOT[SLOT2],~2); + /* TOM key on/off */ + if(v&0x04) FM_KEYON (&OPL->P_CH[8].SLOT[SLOT1], 2); + else FM_KEYOFF(&OPL->P_CH[8].SLOT[SLOT1],~2); + /* TOP-CY key on/off */ + if(v&0x02) FM_KEYON (&OPL->P_CH[8].SLOT[SLOT2], 2); + else FM_KEYOFF(&OPL->P_CH[8].SLOT[SLOT2],~2); + } + else + { + /* BD key off */ + FM_KEYOFF(&OPL->P_CH[6].SLOT[SLOT1],~2); + FM_KEYOFF(&OPL->P_CH[6].SLOT[SLOT2],~2); + /* HH key off */ + FM_KEYOFF(&OPL->P_CH[7].SLOT[SLOT1],~2); + /* SD key off */ + FM_KEYOFF(&OPL->P_CH[7].SLOT[SLOT2],~2); + /* TOM key off */ + FM_KEYOFF(&OPL->P_CH[8].SLOT[SLOT1],~2); + /* TOP-CY off */ + FM_KEYOFF(&OPL->P_CH[8].SLOT[SLOT2],~2); + } + return; + } + /* keyon,block,fnum */ + if( (r&0x0f) > 8) return; + CH = &OPL->P_CH[r&0x0f]; + if(!(r&0x10)) + { /* a0-a8 */ + block_fnum = (CH->block_fnum&0x1f00) | v; + } + else + { /* b0-b8 */ + block_fnum = ((v&0x1f)<<8) | (CH->block_fnum&0xff); + + if(v&0x20) + { + FM_KEYON (&CH->SLOT[SLOT1], 1); + FM_KEYON (&CH->SLOT[SLOT2], 1); + } + else + { + FM_KEYOFF(&CH->SLOT[SLOT1],~1); + FM_KEYOFF(&CH->SLOT[SLOT2],~1); + } + } + /* update */ + if(CH->block_fnum != (uint32_t)block_fnum) + { + uint8_t block = block_fnum >> 10; + + CH->block_fnum = block_fnum; + + CH->ksl_base = ksl_tab[block_fnum>>6]; + CH->fc = OPL->fn_tab[block_fnum&0x03ff] >> (7-block); + + /* BLK 2,1,0 bits -> bits 3,2,1 of kcode */ + CH->kcode = (CH->block_fnum&0x1c00)>>9; + + /* the info below is actually opposite to what is stated in the Manuals (verifed on real YM3812) */ + /* if notesel == 0 -> lsb of kcode is bit 10 (MSB) of fnum */ + /* if notesel == 1 -> lsb of kcode is bit 9 (MSB-1) of fnum */ + if (OPL->mode&0x40) + CH->kcode |= (CH->block_fnum&0x100)>>8; /* notesel == 1 */ + else + CH->kcode |= (CH->block_fnum&0x200)>>9; /* notesel == 0 */ + + /* 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 0xc0: + /* FB,C */ + if( (r&0x0f) > 8) return; + CH = &OPL->P_CH[r&0x0f]; + CH->SLOT[SLOT1].FB = (v>>1)&7 ? ((v>>1)&7) + 7 : 0; + CH->SLOT[SLOT1].CON = v&1; + CH->SLOT[SLOT1].connect1 = CH->SLOT[SLOT1].CON ? &wt->output : &wt->phase_modulation; + break; + case 0xe0: /* waveform select */ + /* simply ignore write to the waveform select register if selecting not enabled in test register */ + if(OPL->wavesel) + { + slot = slot_array[r&0x1f]; + if(slot < 0) return; + CH = &OPL->P_CH[slot/2]; + + CH->SLOT[slot&1].wavetable = (v&0x03)*SIN_LEN; + } + break; + } +} + +static void OPLResetChip(FM_WorkTable *wt, FM_OPL *OPL) +{ + int c,s; + int i; + + OPL->eg_timer = 0; + OPL->eg_cnt = 0; + + OPL->noise_rng = 1; /* noise shift register */ + OPL->mode = 0; /* normal mode */ + OPL_STATUS_RESET(OPL,0x7f); + + /* reset with register write */ + WriteRegister(wt,OPL,0x01,0); /* wavesel disable */ + WriteRegister(wt,OPL,0x02,0); /* Timer1 */ + WriteRegister(wt,OPL,0x03,0); /* Timer2 */ + WriteRegister(wt,OPL,0x04,0); /* IRQ mask clear */ + for(i = 0xff ; i >= 0x20 ; i-- ) WriteRegister(wt,OPL,i,0); + + /* reset operator parameters */ + for( c = 0 ; c < 9 ; c++ ) + { + OPL_CH *CH = &OPL->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; + } + } +} + + +class YM3812 : public OPLEmul +{ +private: + FM_OPL Chip; + FM_WorkTable WorkTable; + +public: + /* Create one of virtual YM3812 */ + YM3812(bool stereo) + { + memset(&WorkTable, 0, sizeof(WorkTable)); + init_tables(); + + /* clear */ + memset(&Chip, 0, sizeof(Chip)); + + /* init global tables */ + OPL_initalize(&Chip); + + Chip.IsStereo = stereo; + + Reset(); + } + + /* YM3812 I/O interface */ + void WriteReg(int reg, int v) + { + WriteRegister(&WorkTable, &Chip, reg & 0xff, v); + } + + void Reset() + { + OPLResetChip(&WorkTable, &Chip); + } + + /* [RH] Full support for MIDI panning */ + void SetPanning(int c, float left, float right) + { + Chip.P_CH[c].LeftVol = left; + Chip.P_CH[c].RightVol = right; + } + + + /* + ** Generate samples for one of the YM3812's + ** + ** '*buffer' is the output buffer pointer + ** 'length' is the number of samples that should be generated + */ + void Update(float *buffer, int length) + { + int i; + + uint8_t rhythm = Chip.rhythm&0x20; + + uint32_t lfo_am_cnt_bak = Chip.lfo_am_cnt; + uint32_t eg_timer_bak = Chip.eg_timer; + uint32_t eg_cnt_bak = Chip.eg_cnt; + + uint32_t lfo_am_cnt_out = lfo_am_cnt_bak; + uint32_t eg_timer_out = eg_timer_bak; + uint32_t eg_cnt_out = eg_cnt_bak; + + for (i = 0; i <= (rhythm ? 5 : 8); ++i) + { + Chip.lfo_am_cnt = lfo_am_cnt_bak; + Chip.eg_timer = eg_timer_bak; + Chip.eg_cnt = eg_cnt_bak; + if (CalcVoice (&WorkTable, &Chip, i, buffer, length)) + { + lfo_am_cnt_out = Chip.lfo_am_cnt; + eg_timer_out = Chip.eg_timer; + eg_cnt_out = Chip.eg_cnt; + } + } + + Chip.lfo_am_cnt = lfo_am_cnt_out; + Chip.eg_timer = eg_timer_out; + Chip.eg_cnt = eg_cnt_out; + + if (rhythm) /* Rhythm part */ + { + Chip.lfo_am_cnt = lfo_am_cnt_bak; + Chip.eg_timer = eg_timer_bak; + Chip.eg_cnt = eg_cnt_bak; + CalcRhythm (&WorkTable, &Chip, buffer, length); + } + } + + void UpdateS(short *buffer, int length) + { + int i; + + uint8_t rhythm = Chip.rhythm&0x20; + + uint32_t lfo_am_cnt_bak = Chip.lfo_am_cnt; + uint32_t eg_timer_bak = Chip.eg_timer; + uint32_t eg_cnt_bak = Chip.eg_cnt; + + uint32_t lfo_am_cnt_out = lfo_am_cnt_bak; + uint32_t eg_timer_out = eg_timer_bak; + uint32_t eg_cnt_out = eg_cnt_bak; + + for (i = 0; i <= (rhythm ? 5 : 8); ++i) + { + Chip.lfo_am_cnt = lfo_am_cnt_bak; + Chip.eg_timer = eg_timer_bak; + Chip.eg_cnt = eg_cnt_bak; + if (CalcVoice (&WorkTable, &Chip, i, buffer, length)) + { + lfo_am_cnt_out = Chip.lfo_am_cnt; + eg_timer_out = Chip.eg_timer; + eg_cnt_out = Chip.eg_cnt; + } + } + + Chip.lfo_am_cnt = lfo_am_cnt_out; + Chip.eg_timer = eg_timer_out; + Chip.eg_cnt = eg_cnt_out; + + if (rhythm) /* Rhythm part */ + { + Chip.lfo_am_cnt = lfo_am_cnt_bak; + Chip.eg_timer = eg_timer_bak; + Chip.eg_cnt = eg_cnt_bak; + CalcRhythm (&WorkTable, &Chip, buffer, length); + } + } + + std::string GetVoiceString(void *chip) + { + FM_OPL *OPL = (FM_OPL *)chip; + char out[9*3]; + + for (int i = 0; i <= 8; ++i) + { + int color; + + if (OPL != NULL && (OPL->P_CH[i].SLOT[0].state != EG_OFF || OPL->P_CH[i].SLOT[1].state != EG_OFF)) + { + color = 'D'; // Green means in use + } + else + { + color = 'A'; // Brick means free + } + out[i*3+0] = '\x1c'; + out[i*3+1] = color; + out[i*3+2] = '*'; + } + return std::string (out, 9*3); + } +}; + +OPLEmul *YM3812Create(bool stereo) +{ + /* emulator create */ + return new YM3812(stereo); +} + +// [RH] Render a whole voice at once. If nothing else, it lets us avoid +// wasting a lot of time on voices that aren't playing anything. + +static bool CalcVoice (FM_WorkTable *wt, FM_OPL *OPL, int voice, float *buffer, int length) +{ + OPL_CH *const CH = &OPL->P_CH[voice]; + int i; + + if (CH->SLOT[0].state == EG_OFF && CH->SLOT[1].state == EG_OFF) + { // Voice is not playing, so don't do anything for it + return false; + } + + for (i = 0; i < length; ++i) + { + advance_lfo(wt, OPL); + + wt->output = 0; + float sample = OPL_CALC_CH(wt, CH); + if (!OPL->IsStereo) + { + buffer[i] += sample; + } + else + { + buffer[i*2] += sample * CH->LeftVol; + buffer[i*2+1] += sample * CH->RightVol; + } + + advance(wt, OPL, voice, voice); + } + return true; +} + +static bool CalcVoice (FM_WorkTable *wt, FM_OPL *OPL, int voice, short *buffer, int length) +{ + OPL_CH *const CH = &OPL->P_CH[voice]; + int i; + + if (CH->SLOT[0].state == EG_OFF && CH->SLOT[1].state == EG_OFF) + { // Voice is not playing, so don't do anything for it + return false; + } + + for (i = 0; i < length; ++i) + { + advance_lfo(wt, OPL); + + wt->output = 0; + short sample = OPL_CALC_CH_S(wt, CH) / 2; + + if (!OPL->IsStereo) + { + buffer[i] += sample; + } + else + { + buffer[i*2] += sample * CH->LeftVol; + buffer[i*2+1] += sample * CH->RightVol; + } + + advance(wt, OPL, voice, voice); + } + return true; +} + +static bool CalcRhythm (FM_WorkTable *wt, FM_OPL *OPL, float *buffer, int length) +{ + int i; + + for (i = 0; i < length; ++i) + { + advance_lfo(wt, OPL); + + wt->output = 0; + OPL_CALC_RH(wt, &OPL->P_CH[0], OPL->noise_rng & 1); + /* [RH] Convert to floating point. */ + float sample = float(wt->output) / 10240; + if (!OPL->IsStereo) + { + buffer[i] += sample; + } + else + { + // [RH] Always use center panning for rhythm. + // The MIDI player doesn't use the rhythm section anyway. + buffer[i*2] += sample * CENTER_PANNING_POWER; + buffer[i*2+1] += sample * CENTER_PANNING_POWER; + } + + advance(wt, OPL, 6, 8); + advance_noise(OPL); + } + return true; +} + +static bool CalcRhythm (FM_WorkTable *wt, FM_OPL *OPL, short *buffer, int length) +{ + int i; + + for (i = 0; i < length; ++i) + { + advance_lfo(wt, OPL); + + wt->output = 0; + OPL_CALC_RH(wt, &OPL->P_CH[0], OPL->noise_rng & 1); + + if (!OPL->IsStereo) + { + buffer[i] += wt->output / 2; + } + else + { + // [RH] Always use center panning for rhythm. + // The MIDI player doesn't use the rhythm section anyway. + buffer[i*2] += (wt->output / 2) * CENTER_PANNING_POWER; + buffer[i*2+1] += (wt->output / 2) * CENTER_PANNING_POWER; + } + + advance(wt, OPL, 6, 8); + advance_noise(OPL); + } + return true; +} |