// license:GPL-2.0+
// copyright-holders:Jarek Burczynski,Tatsuyuki Satoh
/*
**
** File: fm.c -- software implementation of Yamaha FM sound generator
**
** Copyright Jarek Burczynski (bujar at mame dot net)
** Copyright Tatsuyuki Satoh , MultiArcadeMachineEmulator development
**
** Version 1.4.2 (final beta)
**
*/

/*
** History:
**
** 2018 Jean Pierre Cimalando (libOPNMIDI)
** - rewrote pooled memory allocations as ordinary new and delete
**
** 2006-2008 Eke-Eke (Genesis Plus GX), MAME backport by R. Belmont.
**  - implemented PG overflow, aka "detune bug" (Ariel, Comix Zone, Shaq Fu, Spiderman,...), credits to Nemesis
**  - fixed SSG-EG support, credits to Nemesis and additional fixes from Alone Coder
**  - modified EG rates and frequency, tested by Nemesis on real hardware
**  - implemented LFO phase update for CH3 special mode (Warlock birds, Alladin bug sound)
**  - fixed Attack Rate update (Batman & Robin intro)
**  - fixed attenuation level at the start of Substain (Gynoug explosions)
**  - fixed EG decay->substain transition to handle special cases, like SL=0 and Decay rate is very slow (Mega Turrican tracks 03,09...)
**
** 06-23-2007 Zsolt Vasvari:
**  - changed the timing not to require the use of floating point calculations
**
** 03-08-2003 Jarek Burczynski:
**  - fixed YM2608 initial values (after the reset)
**  - fixed flag and irqmask handling (YM2608)
**  - fixed BUFRDY flag handling (YM2608)
**
** 14-06-2003 Jarek Burczynski:
**  - implemented all of the YM2608 status register flags
**  - implemented support for external memory read/write via YM2608
**  - implemented support for deltat memory limit register in YM2608 emulation
**
** 22-05-2003 Jarek Burczynski:
**  - fixed LFO PM calculations (copy&paste bugfix)
**
** 08-05-2003 Jarek Burczynski:
**  - fixed SSG support
**
** 22-04-2003 Jarek Burczynski:
**  - implemented 100% correct LFO generator (verified on real YM2610 and YM2608)
**
** 15-04-2003 Jarek Burczynski:
**  - added support for YM2608's register 0x110 - status mask
**
** 01-12-2002 Jarek Burczynski:
**  - fixed register addressing in YM2608, YM2610, YM2610B chips. (verified on real YM2608)
**    The addressing patch used for early Neo-Geo games can be removed now.
**
** 26-11-2002 Jarek Burczynski, Nicola Salmoria:
**  - recreated YM2608 ADPCM ROM using data from real YM2608's output which leads to:
**  - added emulation of YM2608 drums.
**  - output of YM2608 is two times lower now - same as YM2610 (verified on real YM2608)
**
** 16-08-2002 Jarek Burczynski:
**  - binary exact Envelope Generator (verified on real YM2203);
**    identical to YM2151
**  - corrected 'off by one' error in feedback calculations (when feedback is off)
**  - corrected connection (algorithm) calculation (verified on real YM2203 and YM2610)
**
** 18-12-2001 Jarek Burczynski:
**  - added SSG-EG support (verified on real YM2203)
**
** 12-08-2001 Jarek Burczynski:
**  - corrected sin_tab and tl_tab data (verified on real chip)
**  - corrected feedback calculations (verified on real chip)
**  - corrected phase generator calculations (verified on real chip)
**  - corrected envelope generator calculations (verified on real chip)
**  - corrected FM volume level (YM2610 and YM2610B).
**  - changed YMxxxUpdateOne() functions (YM2203, YM2608, YM2610, YM2610B, YM2612) :
**    this was needed to calculate YM2610 FM channels output correctly.
**    (Each FM channel is calculated as in other chips, but the output of the channel
**    gets shifted right by one *before* sending to accumulator. That was impossible to do
**    with previous implementation).
**
** 23-07-2001 Jarek Burczynski, Nicola Salmoria:
**  - corrected YM2610 ADPCM type A algorithm and tables (verified on real chip)
**
** 11-06-2001 Jarek Burczynski:
**  - corrected end of sample bug in ADPCMA_calc_cha().
**    Real YM2610 checks for equality between current and end addresses (only 20 LSB bits).
**
** 08-12-98 hiro-shi:
** rename ADPCMA -> ADPCMB, ADPCMB -> ADPCMA
** move ROM limit check.(CALC_CH? -> 2610Write1/2)
** test program (ADPCMB_TEST)
** move ADPCM A/B end check.
** ADPCMB repeat flag(no check)
** change ADPCM volume rate (8->16) (32->48).
**
** 09-12-98 hiro-shi:
** change ADPCM volume. (8->16, 48->64)
** replace ym2610 ch0/3 (YM-2610B)
** change ADPCM_SHIFT (10->8) missing bank change 0x4000-0xffff.
** add ADPCM_SHIFT_MASK
** change ADPCMA_DECODE_MIN/MAX.
*/




/************************************************************************/
/*    comment of hiro-shi(Hiromitsu Shioya)                             */
/*    YM2610(B) = OPN-B                                                 */
/*    YM2610  : PSG:3ch FM:4ch ADPCM(18.5KHz):6ch DeltaT ADPCM:1ch      */
/*    YM2610B : PSG:3ch FM:6ch ADPCM(18.5KHz):6ch DeltaT ADPCM:1ch      */
/************************************************************************/

#include "emu.h"

#define YM2610B_WARNING
#include "fm.h"


/* include external DELTA-T unit (when needed) */
#if (BUILD_YM2608||BUILD_YM2610||BUILD_YM2610B)
	#include "ymdeltat.h"
#endif


#if BUILD_YM2203
#include "2203intf.h"
#endif /* BUILD_YM2203 */

#if BUILD_YM2608
#include "2608intf.h"
#endif /* BUILD_YM2608 */

#if (BUILD_YM2610||BUILD_YM2610B)
#include "2610intf.h"
#endif /* (BUILD_YM2610||BUILD_YM2610B) */


/* shared function building option */
#define BUILD_OPN (BUILD_YM2203||BUILD_YM2608||BUILD_YM2610||BUILD_YM2610B)
#define BUILD_OPN_PRESCALER (BUILD_YM2203||BUILD_YM2608)


/* globals */
#define TYPE_SSG    0x01    /* SSG support          */
#define TYPE_LFOPAN 0x02    /* OPN type LFO and PAN */
#define TYPE_6CH    0x04    /* FM 6CH / 3CH         */
#define TYPE_DAC    0x08    /* YM2612's DAC device  */
#define TYPE_ADPCM  0x10    /* two ADPCM units      */
#define TYPE_2610   0x20    /* bogus flag to differentiate 2608 from 2610 */


#define TYPE_YM2203 (TYPE_SSG)
#define TYPE_YM2608 (TYPE_SSG |TYPE_LFOPAN |TYPE_6CH |TYPE_ADPCM)
#define TYPE_YM2610 (TYPE_SSG |TYPE_LFOPAN |TYPE_6CH |TYPE_ADPCM |TYPE_2610)



#define FREQ_SH         16  /* 16.16 fixed point (frequency calculations) */
#define EG_SH           16  /* 16.16 fixed point (envelope generator 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)

#define ENV_BITS        10
#define ENV_LEN         (1<<ENV_BITS)
#define ENV_STEP        (128.0/ENV_LEN)

#define MAX_ATT_INDEX   (ENV_LEN-1) /* 1023 */
#define MIN_ATT_INDEX   (0)         /* 0 */

#define EG_ATT          4
#define EG_DEC          3
#define EG_SUS          2
#define EG_REL          1
#define EG_OFF          0

#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) */


#if (FM_SAMPLE_BITS==16)
	#define FINAL_SH    (0)
	#define MAXOUT      (+32767)
	#define MINOUT      (-32768)
#else
	#define FINAL_SH    (8)
	#define MAXOUT      (+127)
	#define MINOUT      (-128)
#endif


/*  TL_TAB_LEN is calculated as:
*   13 - sinus amplitude bits     (Y axis)
*   2  - sinus sign bit           (Y axis)
*   TL_RES_LEN - sinus resolution (X axis)
*/
#define TL_TAB_LEN (13*2*TL_RES_LEN)
static signed int tl_tab[TL_TAB_LEN];

#define ENV_QUIET       (TL_TAB_LEN>>3)

/* sin waveform table in 'decibel' scale */
static unsigned int sin_tab[SIN_LEN];

/* sustain level table (3dB per step) */
/* bit0, bit1, bit2, bit3, bit4, bit5, bit6 */
/* 1,    2,    4,    8,    16,   32,   64   (value)*/
/* 0.75, 1.5,  3,    6,    12,   24,   48   (dB)*/

/* 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 * (4.0/ENV_STEP) )
static const uint32_t sl_table[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 uint8_t eg_inc[19*RATE_STEPS]={
/*cycle:0 1  2 3  4 5  6 7*/

/* 0 */ 0,1, 0,1, 0,1, 0,1, /* rates 00..11 0 (increment by 0 or 1) */
/* 1 */ 0,1, 0,1, 1,1, 0,1, /* rates 00..11 1 */
/* 2 */ 0,1, 1,1, 0,1, 1,1, /* rates 00..11 2 */
/* 3 */ 0,1, 1,1, 1,1, 1,1, /* rates 00..11 3 */

/* 4 */ 1,1, 1,1, 1,1, 1,1, /* rate 12 0 (increment by 1) */
/* 5 */ 1,1, 1,2, 1,1, 1,2, /* rate 12 1 */
/* 6 */ 1,2, 1,2, 1,2, 1,2, /* rate 12 2 */
/* 7 */ 1,2, 2,2, 1,2, 2,2, /* rate 12 3 */

/* 8 */ 2,2, 2,2, 2,2, 2,2, /* rate 13 0 (increment by 2) */
/* 9 */ 2,2, 2,4, 2,2, 2,4, /* rate 13 1 */
/*10 */ 2,4, 2,4, 2,4, 2,4, /* rate 13 2 */
/*11 */ 2,4, 4,4, 2,4, 4,4, /* rate 13 3 */

/*12 */ 4,4, 4,4, 4,4, 4,4, /* rate 14 0 (increment by 4) */
/*13 */ 4,4, 4,8, 4,4, 4,8, /* rate 14 1 */
/*14 */ 4,8, 4,8, 4,8, 4,8, /* rate 14 2 */
/*15 */ 4,8, 8,8, 4,8, 8,8, /* rate 14 3 */

/*16 */ 8,8, 8,8, 8,8, 8,8, /* rates 15 0, 15 1, 15 2, 15 3 (increment by 8) */
/*17 */ 16,16,16,16,16,16,16,16, /* rates 15 2, 15 3 for attack */
/*18 */ 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(17) in this table - it's directly in the code */
static const uint8_t eg_rate_select[32+64+32]={   /* Envelope Generator rates (32 + 64 rates + 32 RKS) */
/* 32 infinite time rates */
O(18),O(18),O(18),O(18),O(18),O(18),O(18),O(18),
O(18),O(18),O(18),O(18),O(18),O(18),O(18),O(18),
O(18),O(18),O(18),O(18),O(18),O(18),O(18),O(18),
O(18),O(18),O(18),O(18),O(18),O(18),O(18),O(18),

/* rates 00-11 */
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 12 */
O( 4),O( 5),O( 6),O( 7),

/* rate 13 */
O( 8),O( 9),O(10),O(11),

/* rate 14 */
O(12),O(13),O(14),O(15),

/* rate 15 */
O(16),O(16),O(16),O(16),

/* 32 dummy rates (same as 15 3) */
O(16),O(16),O(16),O(16),O(16),O(16),O(16),O(16),
O(16),O(16),O(16),O(16),O(16),O(16),O(16),O(16),
O(16),O(16),O(16),O(16),O(16),O(16),O(16),O(16),
O(16),O(16),O(16),O(16),O(16),O(16),O(16),O(16)

};

#undef O

/*rate  0,    1,    2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15*/
/*shift 11,  10,  9,  8,  7,  6,  5,  4,  3,  2, 1,  0,  0,  0,  0,  0 */
/*mask  2047, 1023, 511, 255, 127, 63, 31, 15, 7,  3, 1,  0,  0,  0,  0,  0 */

#define O(a) (a*1)
static const uint8_t eg_rate_shift[32+64+32]={    /* Envelope Generator counter shifts (32 + 64 rates + 32 RKS) */
/* 32 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),
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 00-11 */
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 12 */
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),

/* 32 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),
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

static const uint8_t dt_tab[4 * 32]={
/* this is YM2151 and YM2612 phase increment data (in 10.10 fixed point format)*/
/* FD=0 */
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* FD=1 */
	0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2,
	2, 3, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7, 8, 8, 8, 8,
/* FD=2 */
	1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5,
	5, 6, 6, 7, 8, 8, 9,10,11,12,13,14,16,16,16,16,
/* FD=3 */
	2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7,
	8 , 8, 9,10,11,12,13,14,16,17,19,20,22,22,22,22
};


/* OPN key frequency number -> key code follow table */
/* fnum higher 4bit -> keycode lower 2bit */
static const uint8_t opn_fktable[16] = {0,0,0,0,0,0,0,1,2,3,3,3,3,3,3,3};


/* 8 LFO speed parameters */
/* each value represents number of samples that one LFO level will last for */
static const uint32_t lfo_samples_per_step[8] = {108, 77, 71, 67, 62, 44, 8, 5};



/*There are 4 different LFO AM depths available, they are:
  0 dB, 1.4 dB, 5.9 dB, 11.8 dB
  Here is how it is generated (in EG steps):

  11.8 dB = 0, 2, 4, 6, 8, 10,12,14,16...126,126,124,122,120,118,....4,2,0
   5.9 dB = 0, 1, 2, 3, 4, 5, 6, 7, 8....63, 63, 62, 61, 60, 59,.....2,1,0
   1.4 dB = 0, 0, 0, 0, 1, 1, 1, 1, 2,...15, 15, 15, 15, 14, 14,.....0,0,0

  (1.4 dB is losing precision as you can see)

  It's implemented as generator from 0..126 with step 2 then a shift
  right N times, where N is:
    8 for 0 dB
    3 for 1.4 dB
    1 for 5.9 dB
    0 for 11.8 dB
*/
static const uint8_t lfo_ams_depth_shift[4] = {8, 3, 1, 0};



/*There are 8 different LFO PM depths available, they are:
  0, 3.4, 6.7, 10, 14, 20, 40, 80 (cents)

  Modulation level at each depth depends on F-NUMBER bits: 4,5,6,7,8,9,10
  (bits 8,9,10 = FNUM MSB from OCT/FNUM register)

  Here we store only first quarter (positive one) of full waveform.
  Full table (lfo_pm_table) containing all 128 waveforms is build
  at run (init) time.

  One value in table below represents 4 (four) basic LFO steps
  (1 PM step = 4 AM steps).

  For example:
   at LFO SPEED=0 (which is 108 samples per basic LFO step)
   one value from "lfo_pm_output" table lasts for 432 consecutive
   samples (4*108=432) and one full LFO waveform cycle lasts for 13824
   samples (32*432=13824; 32 because we store only a quarter of whole
            waveform in the table below)
*/
static const uint8_t lfo_pm_output[7*8][8]={ /* 7 bits meaningful (of F-NUMBER), 8 LFO output levels per one depth (out of 32), 8 LFO depths */
/* FNUM BIT 4: 000 0001xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 2 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 3 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 4 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 5 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 6 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 7 */ {0,   0,   0,   0,   1,   1,   1,   1},

/* FNUM BIT 5: 000 0010xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 2 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 3 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 4 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 5 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 6 */ {0,   0,   0,   0,   1,   1,   1,   1},
/* DEPTH 7 */ {0,   0,   1,   1,   2,   2,   2,   3},

/* FNUM BIT 6: 000 0100xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 2 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 3 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 4 */ {0,   0,   0,   0,   0,   0,   0,   1},
/* DEPTH 5 */ {0,   0,   0,   0,   1,   1,   1,   1},
/* DEPTH 6 */ {0,   0,   1,   1,   2,   2,   2,   3},
/* DEPTH 7 */ {0,   0,   2,   3,   4,   4,   5,   6},

/* FNUM BIT 7: 000 1000xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 2 */ {0,   0,   0,   0,   0,   0,   1,   1},
/* DEPTH 3 */ {0,   0,   0,   0,   1,   1,   1,   1},
/* DEPTH 4 */ {0,   0,   0,   1,   1,   1,   1,   2},
/* DEPTH 5 */ {0,   0,   1,   1,   2,   2,   2,   3},
/* DEPTH 6 */ {0,   0,   2,   3,   4,   4,   5,   6},
/* DEPTH 7 */ {0,   0,   4,   6,   8,   8, 0xa, 0xc},

/* FNUM BIT 8: 001 0000xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   1,   1,   1,   1},
/* DEPTH 2 */ {0,   0,   0,   1,   1,   1,   2,   2},
/* DEPTH 3 */ {0,   0,   1,   1,   2,   2,   3,   3},
/* DEPTH 4 */ {0,   0,   1,   2,   2,   2,   3,   4},
/* DEPTH 5 */ {0,   0,   2,   3,   4,   4,   5,   6},
/* DEPTH 6 */ {0,   0,   4,   6,   8,   8, 0xa, 0xc},
/* DEPTH 7 */ {0,   0,   8, 0xc,0x10,0x10,0x14,0x18},

/* FNUM BIT 9: 010 0000xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   2,   2,   2,   2},
/* DEPTH 2 */ {0,   0,   0,   2,   2,   2,   4,   4},
/* DEPTH 3 */ {0,   0,   2,   2,   4,   4,   6,   6},
/* DEPTH 4 */ {0,   0,   2,   4,   4,   4,   6,   8},
/* DEPTH 5 */ {0,   0,   4,   6,   8,   8, 0xa, 0xc},
/* DEPTH 6 */ {0,   0,   8, 0xc,0x10,0x10,0x14,0x18},
/* DEPTH 7 */ {0,   0,0x10,0x18,0x20,0x20,0x28,0x30},

/* FNUM BIT10: 100 0000xxxx */
/* DEPTH 0 */ {0,   0,   0,   0,   0,   0,   0,   0},
/* DEPTH 1 */ {0,   0,   0,   0,   4,   4,   4,   4},
/* DEPTH 2 */ {0,   0,   0,   4,   4,   4,   8,   8},
/* DEPTH 3 */ {0,   0,   4,   4,   8,   8, 0xc, 0xc},
/* DEPTH 4 */ {0,   0,   4,   8,   8,   8, 0xc,0x10},
/* DEPTH 5 */ {0,   0,   8, 0xc,0x10,0x10,0x14,0x18},
/* DEPTH 6 */ {0,   0,0x10,0x18,0x20,0x20,0x28,0x30},
/* DEPTH 7 */ {0,   0,0x20,0x30,0x40,0x40,0x50,0x60},

};

/* all 128 LFO PM waveforms */
static int32_t lfo_pm_table[128*8*32]; /* 128 combinations of 7 bits meaningful (of F-NUMBER), 8 LFO depths, 32 LFO output levels per one depth */


// libOPNMIDI: pan law table
static const uint16_t panlawtable[] =
{
    65535, 65529, 65514, 65489, 65454, 65409, 65354, 65289,
    65214, 65129, 65034, 64929, 64814, 64689, 64554, 64410,
    64255, 64091, 63917, 63733, 63540, 63336, 63123, 62901,
    62668, 62426, 62175, 61914, 61644, 61364, 61075, 60776,
    60468, 60151, 59825, 59489, 59145, 58791, 58428, 58057,
    57676, 57287, 56889, 56482, 56067, 55643, 55211, 54770,
    54320, 53863, 53397, 52923, 52441, 51951, 51453, 50947,
    50433, 49912, 49383, 48846, 48302, 47750, 47191,
    46340, /* Center left */
    46340, /* Center right */
    45472, 44885, 44291, 43690, 43083, 42469, 41848, 41221,
    40588, 39948, 39303, 38651, 37994, 37330, 36661, 35986,
    35306, 34621, 33930, 33234, 32533, 31827, 31116, 30400,
    29680, 28955, 28225, 27492, 26754, 26012, 25266, 24516,
    23762, 23005, 22244, 21480, 20713, 19942, 19169, 18392,
    17613, 16831, 16046, 15259, 14469, 13678, 12884, 12088,
    11291, 10492, 9691, 8888, 8085, 7280, 6473, 5666,
    4858, 4050, 3240, 2431, 1620, 810, 0
};


/* register number to channel number , slot offset */
#define OPN_CHAN(N) (N&3)
#define OPN_SLOT(N) ((N>>2)&3)

/* slot number */
#define SLOT1 0
#define SLOT2 2
#define SLOT3 1
#define SLOT4 3

/* bit0 = Right enable , bit1 = Left enable */
#define OUTD_RIGHT  1
#define OUTD_LEFT   2
#define OUTD_CENTER 3


/* save output as raw 16-bit sample */
/* #define SAVE_SAMPLE */

#ifdef SAVE_SAMPLE
static FILE *sample[1];
	#if 1   /*save to MONO file */
		#define SAVE_ALL_CHANNELS \
		{   signed int pom = lt; \
			fputc((unsigned short)pom&0xff,sample[0]); \
			fputc(((unsigned short)pom>>8)&0xff,sample[0]); \
		}
	#else   /*save to STEREO file */
		#define SAVE_ALL_CHANNELS \
		{   signed int pom = lt; \
			fputc((unsigned short)pom&0xff,sample[0]); \
			fputc(((unsigned short)pom>>8)&0xff,sample[0]); \
			pom = rt; \
			fputc((unsigned short)pom&0xff,sample[0]); \
			fputc(((unsigned short)pom>>8)&0xff,sample[0]); \
		}
	#endif
#endif


/* struct describing a single operator (SLOT) */
struct FM_SLOT
{
	int32_t   *DT;        /* detune          :dt_tab[DT] */
	uint8_t   KSR;        /* key scale rate  :3-KSR */
	uint32_t  ar;         /* attack rate  */
	uint32_t  d1r;        /* decay rate   */
	uint32_t  d2r;        /* sustain rate */
	uint32_t  rr;         /* release rate */
	uint8_t   ksr;        /* key scale rate  :kcode>>(3-KSR) */
	uint32_t  mul;        /* multiple        :ML_TABLE[ML] */

	/* Phase Generator */
	uint32_t  phase;      /* phase counter */
	int32_t   Incr;       /* phase step */

	/* Envelope Generator */
	uint8_t   state;      /* phase type */
	uint32_t  tl;         /* total level: TL << 3 */
	int32_t   volume;     /* envelope counter */
	uint32_t  sl;         /* sustain level:sl_table[SL] */
	uint32_t  vol_out;    /* current output from EG circuit (without AM from LFO) */

	uint8_t   eg_sh_ar;   /*  (attack state) */
	uint8_t   eg_sel_ar;  /*  (attack state) */
	uint8_t   eg_sh_d1r;  /*  (decay state) */
	uint8_t   eg_sel_d1r; /*  (decay state) */
	uint8_t   eg_sh_d2r;  /*  (sustain state) */
	uint8_t   eg_sel_d2r; /*  (sustain state) */
	uint8_t   eg_sh_rr;   /*  (release state) */
	uint8_t   eg_sel_rr;  /*  (release state) */

	uint8_t   ssg;        /* SSG-EG waveform */
	uint8_t   ssgn;       /* SSG-EG negated output */

	uint32_t  key;        /* 0=last key was KEY OFF, 1=KEY ON */

	/* LFO */
	uint32_t  AMmask;     /* AM enable flag */

};

struct FM_CH
{
	FM_SLOT SLOT[4];    /* four SLOTs (operators) */

	uint8_t   ALGO;       /* algorithm */
	uint8_t   FB;         /* feedback shift */
	int32_t   op1_out[2]; /* op1 output for feedback */

	int32_t   *connect1;  /* SLOT1 output pointer */
	int32_t   *connect3;  /* SLOT3 output pointer */
	int32_t   *connect2;  /* SLOT2 output pointer */
	int32_t   *connect4;  /* SLOT4 output pointer */

	int32_t   *mem_connect;/* where to put the delayed sample (MEM) */
	int32_t   mem_value;  /* delayed sample (MEM) value */

	int32_t   pms;        /* channel PMS */
	uint8_t   ams;        /* channel AMS */

	uint32_t  fc;         /* fnum,blk:adjusted to sample rate */
	uint8_t   kcode;      /* key code:                        */
	uint32_t  block_fnum; /* current blk/fnum value for this slot (can be different betweeen slots of one channel in 3slot mode) */

	int32_t pan_volume_l; /* libOPNMIDI: left panning amount */
	int32_t pan_volume_r; /* libOPNMIDI: right panning amount */
};


struct FM_ST
{
	device_t *device;
	int         clock;              /* master clock  (Hz)   */
	int         rate;               /* sampling rate (Hz)   */
	double      freqbase;           /* frequency base       */
	int         timer_prescaler;    /* timer prescaler      */
#if FM_BUSY_FLAG_SUPPORT
	TIME_TYPE   busy_expiry_time;   /* expiry time of the busy status */
#endif
	uint8_t       address;            /* address register     */
	uint8_t       irq;                /* interrupt level      */
	uint8_t       irqmask;            /* irq mask             */
	uint8_t       status;             /* status flag          */
	uint32_t      mode;               /* mode  CSM / 3SLOT    */
	uint8_t       prescaler_sel;      /* prescaler selector   */
	uint8_t       fn_h;               /* freq latch           */
	int32_t       TA;                 /* timer a              */
	int32_t       TAC;                /* timer a counter      */
	uint8_t       TB;                 /* timer b              */
	int32_t       TBC;                /* timer b counter      */
	/* local time tables */
	int32_t       dt_tab[8][32];      /* DeTune table         */
	/* Extention Timer and IRQ handler */
	FM_TIMERHANDLER timer_handler;
	FM_IRQHANDLER   IRQ_Handler;
	const ssg_callbacks *SSG;
};



/***********************************************************/
/* OPN unit                                                */
/***********************************************************/

/* OPN 3slot struct */
struct FM_3SLOT
{
	uint32_t  fc[3];          /* fnum3,blk3: calculated */
	uint8_t   fn_h;           /* freq3 latch */
	uint8_t   kcode[3];       /* key code */
	uint32_t  block_fnum[3];  /* current fnum value for this slot (can be different betweeen slots of one channel in 3slot mode) */
};

/* OPN/A/B common state */
struct FM_OPN
{
	uint8_t   type;           /* chip type */
	FM_ST   ST;             /* general state */
	FM_3SLOT SL3;           /* 3 slot mode state */
	FM_CH   *P_CH;          /* pointer of CH */
	unsigned int pan[6*2];  /* fm channels output masks (0xffffffff = enable) */

	uint32_t  eg_cnt;         /* global envelope generator counter */
	uint32_t  eg_timer;       /* global envelope generator counter works at frequency = chipclock/64/3 */
	uint32_t  eg_timer_add;   /* step of eg_timer */
	uint32_t  eg_timer_overflow;/* envelope generator timer overflows every 3 samples (on real chip) */


	/* there are 2048 FNUMs that can be generated using FNUM/BLK registers
	    but LFO works with one more bit of a precision so we really need 4096 elements */

	uint32_t  fn_table[4096]; /* fnumber->increment counter */
	uint32_t fn_max;    /* maximal phase increment (used for phase overflow) */

	/* LFO */
	uint32_t  LFO_AM;         /* runtime LFO calculations helper */
	int32_t   LFO_PM;         /* runtime LFO calculations helper */

	uint32_t  lfo_cnt;
	uint32_t  lfo_inc;

	uint32_t  lfo_freq[8];    /* LFO FREQ table */

	int32_t   m2,c1,c2;       /* Phase Modulation input for operators 2,3,4 */
	int32_t   mem;            /* one sample delay memory */

	int32_t   out_fm[8];      /* outputs of working channels */

#if (BUILD_YM2608||BUILD_YM2610||BUILD_YM2610B)
	int32_t   out_adpcm[4];   /* channel output NONE,LEFT,RIGHT or CENTER for YM2608/YM2610 ADPCM */
	int32_t   out_delta[4];   /* channel output NONE,LEFT,RIGHT or CENTER for YM2608/YM2610 DELTAT*/
#endif
};



/* current chip state */

/* log output level */
#define LOG_ERR  3      /* ERROR       */
#define LOG_WAR  2      /* WARNING     */
#define LOG_INF  1      /* INFORMATION */
#define LOG_LEVEL LOG_INF

#ifndef __RAINE__
#define LOG(d,n,x) do { if( (n)>=LOG_LEVEL ) d->logerror x; } while (0)
#endif

/* limitter */
#define Limit(val, max,min) { \
	if ( val > max )      val = max; \
	else if ( val < min ) val = min; \
}


/* status set and IRQ handling */
static inline void FM_STATUS_SET(FM_ST *ST,int flag)
{
	/* set status flag */
	ST->status |= flag;
	if ( !(ST->irq) && (ST->status & ST->irqmask) )
	{
		ST->irq = 1;
		/* callback user interrupt handler (IRQ is OFF to ON) */
		if(ST->IRQ_Handler) (ST->IRQ_Handler)(ST->device,1);
	}
}

/* status reset and IRQ handling */
static inline void FM_STATUS_RESET(FM_ST *ST,int flag)
{
	/* reset status flag */
	ST->status &=~flag;
	if ( (ST->irq) && !(ST->status & ST->irqmask) )
	{
		ST->irq = 0;
		/* callback user interrupt handler (IRQ is ON to OFF) */
		if(ST->IRQ_Handler) (ST->IRQ_Handler)(ST->device,0);
	}
}

/* IRQ mask set */
static inline void FM_IRQMASK_SET(FM_ST *ST,int flag)
{
	ST->irqmask = flag;
	/* IRQ handling check */
	FM_STATUS_SET(ST,0);
	FM_STATUS_RESET(ST,0);
}

/* OPN Mode Register Write */
static inline void set_timers( FM_ST *ST, device_t *n, int v )
{
	/* b7 = CSM MODE */
	/* b6 = 3 slot mode */
	/* b5 = reset b */
	/* b4 = reset a */
	/* b3 = timer enable b */
	/* b2 = timer enable a */
	/* b1 = load b */
	/* b0 = load a */
	ST->mode = v;

	/* reset Timer b flag */
	if( v & 0x20 )
		FM_STATUS_RESET(ST,0x02);
	/* reset Timer a flag */
	if( v & 0x10 )
		FM_STATUS_RESET(ST,0x01);
	/* load b */
	if( v & 0x02 )
	{
		if( ST->TBC == 0 )
		{
			ST->TBC = ( 256-ST->TB)<<4;
			/* External timer handler */
			if (ST->timer_handler) (ST->timer_handler)(n,1,ST->TBC * ST->timer_prescaler,ST->clock);
		}
	}
	else
	{   /* stop timer b */
		if( ST->TBC != 0 )
		{
			ST->TBC = 0;
			if (ST->timer_handler) (ST->timer_handler)(n,1,0,ST->clock);
		}
	}
	/* load a */
	if( v & 0x01 )
	{
		if( ST->TAC == 0 )
		{
			ST->TAC = (1024-ST->TA);
			/* External timer handler */
			if (ST->timer_handler) (ST->timer_handler)(n,0,ST->TAC * ST->timer_prescaler,ST->clock);
		}
	}
	else
	{   /* stop timer a */
		if( ST->TAC != 0 )
		{
			ST->TAC = 0;
			if (ST->timer_handler) (ST->timer_handler)(n,0,0,ST->clock);
		}
	}
}


/* Timer A Overflow */
static inline void TimerAOver(FM_ST *ST)
{
	/* set status (if enabled) */
	if(ST->mode & 0x04) FM_STATUS_SET(ST,0x01);
	/* clear or reload the counter */
	ST->TAC = (1024-ST->TA);
	if (ST->timer_handler) (ST->timer_handler)(ST->device,0,ST->TAC * ST->timer_prescaler,ST->clock);
}
/* Timer B Overflow */
static inline void TimerBOver(FM_ST *ST)
{
	/* set status (if enabled) */
	if(ST->mode & 0x08) FM_STATUS_SET(ST,0x02);
	/* clear or reload the counter */
	ST->TBC = ( 256-ST->TB)<<4;
	if (ST->timer_handler) (ST->timer_handler)(ST->device,1,ST->TBC * ST->timer_prescaler,ST->clock);
}


#if FM_INTERNAL_TIMER
/* ----- internal timer mode , update timer */

/* ---------- calculate timer A ---------- */
	#define INTERNAL_TIMER_A(ST,CSM_CH)                 \
	{                                                   \
		if( ST->TAC &&  (ST->timer_handler==0) )        \
			if( (ST->TAC -= (int)(ST->freqbase*4096)) <= 0 )    \
			{                                           \
				TimerAOver( ST );                       \
				/* CSM mode total level latch and auto key on */    \
				if( ST->mode & 0x80 )                   \
					CSMKeyControll( CSM_CH );           \
			}                                           \
	}
/* ---------- calculate timer B ---------- */
	#define INTERNAL_TIMER_B(ST,step)                       \
	{                                                       \
		if( ST->TBC && (ST->timer_handler==0) )             \
			if( (ST->TBC -= (int)(ST->freqbase*4096*step)) <= 0 )   \
				TimerBOver( ST );                           \
	}
#else /* FM_INTERNAL_TIMER */
/* external timer mode */
#define INTERNAL_TIMER_A(ST,CSM_CH)
#define INTERNAL_TIMER_B(ST,step)
#endif /* FM_INTERNAL_TIMER */



#if FM_BUSY_FLAG_SUPPORT
#define FM_BUSY_CLEAR(ST) ((ST)->busy_expiry_time = UNDEFINED_TIME)
static inline uint8_t FM_STATUS_FLAG(FM_ST *ST)
{
	if( COMPARE_TIMES(ST->busy_expiry_time, UNDEFINED_TIME) != 0 )
	{
		if (COMPARE_TIMES(ST->busy_expiry_time, FM_GET_TIME_NOW(&ST->device->machine())) > 0)
			return ST->status | 0x80;   /* with busy */
		/* expire */
		FM_BUSY_CLEAR(ST);
	}
	return ST->status;
}
static inline void FM_BUSY_SET(FM_ST *ST,int busyclock )
{
	TIME_TYPE expiry_period = MULTIPLY_TIME_BY_INT(attotime::from_hz(ST->clock), busyclock * ST->timer_prescaler);
	ST->busy_expiry_time = ADD_TIMES(FM_GET_TIME_NOW(&ST->device->machine()), expiry_period);
}
#else
#define FM_STATUS_FLAG(ST) ((ST)->status)
#define FM_BUSY_SET(ST,bclock) {}
#define FM_BUSY_CLEAR(ST) {}
#endif




static inline void FM_KEYON(uint8_t type, FM_CH *CH , int s )
{
	FM_SLOT *SLOT = &CH->SLOT[s];
	(void)type;
	if( !SLOT->key )
	{
		SLOT->key = 1;
		SLOT->phase = 0;        /* restart Phase Generator */
		SLOT->ssgn = (SLOT->ssg & 0x04) >> 1;
		SLOT->state = EG_ATT;
	}
}

static inline void FM_KEYOFF(FM_CH *CH , int s )
{
	FM_SLOT *SLOT = &CH->SLOT[s];
	if( SLOT->key )
	{
		SLOT->key = 0;
		if (SLOT->state>EG_REL)
			SLOT->state = EG_REL;/* phase -> Release */
	}
}

/* set algorithm connection */
static void setup_connection( FM_OPN *OPN, FM_CH *CH, int ch )
{
	int32_t *carrier = &OPN->out_fm[ch];

	int32_t **om1 = &CH->connect1;
	int32_t **om2 = &CH->connect3;
	int32_t **oc1 = &CH->connect2;

	int32_t **memc = &CH->mem_connect;

	switch( CH->ALGO )
	{
	case 0:
		/* M1---C1---MEM---M2---C2---OUT */
		*om1 = &OPN->c1;
		*oc1 = &OPN->mem;
		*om2 = &OPN->c2;
		*memc= &OPN->m2;
		break;
	case 1:
		/* M1------+-MEM---M2---C2---OUT */
		/*      C1-+                     */
		*om1 = &OPN->mem;
		*oc1 = &OPN->mem;
		*om2 = &OPN->c2;
		*memc= &OPN->m2;
		break;
	case 2:
		/* M1-----------------+-C2---OUT */
		/*      C1---MEM---M2-+          */
		*om1 = &OPN->c2;
		*oc1 = &OPN->mem;
		*om2 = &OPN->c2;
		*memc= &OPN->m2;
		break;
	case 3:
		/* M1---C1---MEM------+-C2---OUT */
		/*                 M2-+          */
		*om1 = &OPN->c1;
		*oc1 = &OPN->mem;
		*om2 = &OPN->c2;
		*memc= &OPN->c2;
		break;
	case 4:
		/* M1---C1-+-OUT */
		/* M2---C2-+     */
		/* MEM: not used */
		*om1 = &OPN->c1;
		*oc1 = carrier;
		*om2 = &OPN->c2;
		*memc= &OPN->mem;   /* store it anywhere where it will not be used */
		break;
	case 5:
		/*    +----C1----+     */
		/* M1-+-MEM---M2-+-OUT */
		/*    +----C2----+     */
		*om1 = NULLPTR;   /* special mark */
		*oc1 = carrier;
		*om2 = carrier;
		*memc= &OPN->m2;
		break;
	case 6:
		/* M1---C1-+     */
		/*      M2-+-OUT */
		/*      C2-+     */
		/* MEM: not used */
		*om1 = &OPN->c1;
		*oc1 = carrier;
		*om2 = carrier;
		*memc= &OPN->mem;   /* store it anywhere where it will not be used */
		break;
	case 7:
		/* M1-+     */
		/* C1-+-OUT */
		/* M2-+     */
		/* C2-+     */
		/* MEM: not used*/
		*om1 = carrier;
		*oc1 = carrier;
		*om2 = carrier;
		*memc= &OPN->mem;   /* store it anywhere where it will not be used */
		break;
	}

	CH->connect4 = carrier;
}

/* set detune & multiple */
static inline void set_det_mul(FM_ST *ST,FM_CH *CH,FM_SLOT *SLOT,int v)
{
	SLOT->mul = (v&0x0f)? (v&0x0f)*2 : 1;
	SLOT->DT  = ST->dt_tab[(v>>4)&7];
	CH->SLOT[SLOT1].Incr=-1;
}

/* set total level */
static inline void set_tl(FM_CH *CH,FM_SLOT *SLOT , int v)
{
	(void)CH;
	SLOT->tl = (v&0x7f)<<(ENV_BITS-7); /* 7bit TL */
}

/* set attack rate & key scale  */
static inline void set_ar_ksr(uint8_t type, FM_CH *CH,FM_SLOT *SLOT,int v)
{
	uint8_t old_KSR = SLOT->KSR;
	(void)type;

	SLOT->ar = (v&0x1f) ? 32 + ((v&0x1f)<<1) : 0;

	SLOT->KSR = 3-(v>>6);
	if (SLOT->KSR != old_KSR)
	{
		CH->SLOT[SLOT1].Incr=-1;
	}

	/* refresh Attack rate */
	if ((SLOT->ar + SLOT->ksr) < 32+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 = 17*RATE_STEPS;
	}
}

/* set decay rate */
static inline void set_dr(uint8_t type, FM_SLOT *SLOT,int v)
{
	(void)type;
	SLOT->d1r = (v&0x1f) ? 32 + ((v&0x1f)<<1) : 0;

	SLOT->eg_sh_d1r = eg_rate_shift [SLOT->d1r + SLOT->ksr];
	SLOT->eg_sel_d1r= eg_rate_select[SLOT->d1r + SLOT->ksr];
}

/* set sustain rate */
static inline void set_sr(uint8_t type, FM_SLOT *SLOT,int v)
{
	(void)type;
	SLOT->d2r = (v&0x1f) ? 32 + ((v&0x1f)<<1) : 0;

	SLOT->eg_sh_d2r = eg_rate_shift [SLOT->d2r + SLOT->ksr];
	SLOT->eg_sel_d2r= eg_rate_select[SLOT->d2r + SLOT->ksr];
}

/* set release rate */
static inline void set_sl_rr(uint8_t type, FM_SLOT *SLOT,int v)
{
	(void)type;
	SLOT->sl = sl_table[ v>>4 ];

	SLOT->rr  = 34 + ((v&0x0f)<<2);

	SLOT->eg_sh_rr  = eg_rate_shift [SLOT->rr  + SLOT->ksr];
	SLOT->eg_sel_rr = eg_rate_select[SLOT->rr  + SLOT->ksr];
}



static inline signed int op_calc(uint32_t phase, unsigned int env, signed int pm)
{
	uint32_t p;

	p = (env<<3) + sin_tab[ ( ((signed int)((phase & ~FREQ_MASK) + (pm<<15))) >> 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)
{
	uint32_t p;

	p = (env<<3) + sin_tab[ ( ((signed int)((phase & ~FREQ_MASK) + pm      )) >> FREQ_SH ) & SIN_MASK ];

	if (p >= TL_TAB_LEN)
		return 0;
	return tl_tab[p];
}

/* advance LFO to next sample */
static inline void advance_lfo(FM_OPN *OPN)
{
	uint8_t pos;

	if (OPN->lfo_inc)   /* LFO enabled ? */
	{
		OPN->lfo_cnt += OPN->lfo_inc;

		pos = (OPN->lfo_cnt >> LFO_SH) & 127;


		/* update AM when LFO output changes */

		/* actually I can't optimize is this way without rewriting chan_calc()
		to use chip->lfo_am instead of global lfo_am */
		{
			/* triangle */
			/* AM: 0 to 126 step +2, 126 to 0 step -2 */
			if (pos<64)
				OPN->LFO_AM = (pos&63) * 2;
			else
				OPN->LFO_AM = 126 - ((pos&63) * 2);
		}

		/* PM works with 4 times slower clock */
		pos >>= 2;
		/* update PM when LFO output changes */
		/*if (prev_pos != pos)*/ /* can't use global lfo_pm for this optimization, must be chip->lfo_pm instead*/
		{
			OPN->LFO_PM = pos;
		}

	}
	else
	{
		OPN->LFO_AM = 0;
		OPN->LFO_PM = 0;
	}
}

/* changed from static inline to static here to work around gcc 4.2.1 codegen bug */
static void advance_eg_channel(FM_OPN *OPN, FM_SLOT *SLOT)
{
	unsigned int out;
	unsigned int swap_flag;
	unsigned int i;


	i = 4; /* four operators per channel */
	do
	{
		/* reset SSG-EG swap flag */
		swap_flag = 0;

		switch(SLOT->state)
		{
		case EG_ATT:        /* attack phase */
			if ( !(OPN->eg_cnt & ((1<<SLOT->eg_sh_ar)-1) ) )
			{
				SLOT->volume += (~SLOT->volume *
									(eg_inc[SLOT->eg_sel_ar + ((OPN->eg_cnt>>SLOT->eg_sh_ar)&7)])
								) >>4;

				if (SLOT->volume <= MIN_ATT_INDEX)
				{
					SLOT->volume = MIN_ATT_INDEX;
					SLOT->state = EG_DEC;
				}
			}
		break;

		case EG_DEC:    /* decay phase */
			{
				if (SLOT->ssg&0x08) /* SSG EG type envelope selected */
				{
					if ( !(OPN->eg_cnt & ((1<<SLOT->eg_sh_d1r)-1) ) )
					{
						SLOT->volume += 4 * eg_inc[SLOT->eg_sel_d1r + ((OPN->eg_cnt>>SLOT->eg_sh_d1r)&7)];

						if ( SLOT->volume >= (int32_t)(SLOT->sl) )
							SLOT->state = EG_SUS;
					}
				}
				else
				{
					if ( !(OPN->eg_cnt & ((1<<SLOT->eg_sh_d1r)-1) ) )
					{
						SLOT->volume += eg_inc[SLOT->eg_sel_d1r + ((OPN->eg_cnt>>SLOT->eg_sh_d1r)&7)];

						if ( SLOT->volume >= (int32_t)(SLOT->sl) )
							SLOT->state = EG_SUS;
					}
				}
			}
		break;

		case EG_SUS:    /* sustain phase */
			if (SLOT->ssg&0x08) /* SSG EG type envelope selected */
			{
				if ( !(OPN->eg_cnt & ((1<<SLOT->eg_sh_d2r)-1) ) )
				{
					SLOT->volume += 4 * eg_inc[SLOT->eg_sel_d2r + ((OPN->eg_cnt>>SLOT->eg_sh_d2r)&7)];

					if ( SLOT->volume >= ENV_QUIET )
					{
						SLOT->volume = MAX_ATT_INDEX;

						if (SLOT->ssg&0x01) /* bit 0 = hold */
						{
							if (SLOT->ssgn&1)   /* have we swapped once ??? */
							{
								/* yes, so do nothing, just hold current level */
							}
							else
								swap_flag = (SLOT->ssg&0x02) | 1 ; /* bit 1 = alternate */

						}
						else
						{
							/* same as KEY-ON operation */

							/* restart of the Phase Generator should be here */
							SLOT->phase = 0;

							{
								/* phase -> Attack */
								SLOT->volume = 511;
								SLOT->state = EG_ATT;
							}

							swap_flag = (SLOT->ssg&0x02); /* bit 1 = alternate */
						}
					}
				}
			}
			else
			{
				if ( !(OPN->eg_cnt & ((1<<SLOT->eg_sh_d2r)-1) ) )
				{
					SLOT->volume += eg_inc[SLOT->eg_sel_d2r + ((OPN->eg_cnt>>SLOT->eg_sh_d2r)&7)];

					if ( SLOT->volume >= MAX_ATT_INDEX )
					{
						SLOT->volume = MAX_ATT_INDEX;
						/* do not change SLOT->state (verified on real chip) */
					}
				}

			}
		break;

		case EG_REL:    /* release phase */
				if ( !(OPN->eg_cnt & ((1<<SLOT->eg_sh_rr)-1) ) )
				{
					/* SSG-EG affects Release phase also (Nemesis) */
					SLOT->volume += eg_inc[SLOT->eg_sel_rr + ((OPN->eg_cnt>>SLOT->eg_sh_rr)&7)];

					if ( SLOT->volume >= MAX_ATT_INDEX )
					{
						SLOT->volume = MAX_ATT_INDEX;
						SLOT->state = EG_OFF;
					}
				}
		break;

		}


		out = ((uint32_t)SLOT->volume);

				/* negate output (changes come from alternate bit, init comes from attack bit) */
		if ((SLOT->ssg&0x08) && (SLOT->ssgn&2) && (SLOT->state > EG_REL))
			out ^= MAX_ATT_INDEX;

		/* we need to store the result here because we are going to change ssgn
		    in next instruction */
		SLOT->vol_out = out + SLOT->tl;

				/* reverse SLOT inversion flag */
		SLOT->ssgn ^= swap_flag;

		SLOT++;
		i--;
	}while (i);

}



#define volume_calc(OP) ((OP)->vol_out + (AM & (OP)->AMmask))

static inline void update_phase_lfo_slot(FM_OPN *OPN, FM_SLOT *SLOT, int32_t pms, uint32_t block_fnum)
{
	uint32_t fnum_lfo  = ((block_fnum & 0x7f0) >> 4) * 32 * 8;
	int32_t  lfo_fn_table_index_offset = lfo_pm_table[ fnum_lfo + pms + OPN->LFO_PM ];

	if (lfo_fn_table_index_offset)    /* LFO phase modulation active */
	{
		uint8_t blk;
		uint32_t fn;
		int kc, fc;

		block_fnum = block_fnum*2 + lfo_fn_table_index_offset;

		blk = (block_fnum&0x7000) >> 12;
		fn  = block_fnum & 0xfff;

		/* keyscale code */
		kc = (blk<<2) | opn_fktable[fn >> 8];

		/* phase increment counter */
		fc = (OPN->fn_table[fn]>>(7-blk)) + SLOT->DT[kc];

		/* detects frequency overflow (credits to Nemesis) */
		if (fc < 0) fc += OPN->fn_max;

		/* update phase */
		SLOT->phase += (fc * SLOT->mul) >> 1;
	}
	else    /* LFO phase modulation  = zero */
	{
		SLOT->phase += SLOT->Incr;
	}
}

static inline void update_phase_lfo_channel(FM_OPN *OPN, FM_CH *CH)
{
	uint32_t block_fnum = CH->block_fnum;

	uint32_t fnum_lfo  = ((block_fnum & 0x7f0) >> 4) * 32 * 8;
	int32_t  lfo_fn_table_index_offset = lfo_pm_table[ fnum_lfo + CH->pms + OPN->LFO_PM ];

	if (lfo_fn_table_index_offset)    /* LFO phase modulation active */
	{
			uint8_t blk;
			uint32_t fn;
		int kc, fc, finc;

		block_fnum = block_fnum*2 + lfo_fn_table_index_offset;

			blk = (block_fnum&0x7000) >> 12;
			fn  = block_fnum & 0xfff;

		/* keyscale code */
			kc = (blk<<2) | opn_fktable[fn >> 8];

			/* phase increment counter */
		fc = (OPN->fn_table[fn]>>(7-blk));

		/* detects frequency overflow (credits to Nemesis) */
		finc = fc + CH->SLOT[SLOT1].DT[kc];

		if (finc < 0) finc += OPN->fn_max;
		CH->SLOT[SLOT1].phase += (finc*CH->SLOT[SLOT1].mul) >> 1;

		finc = fc + CH->SLOT[SLOT2].DT[kc];
		if (finc < 0) finc += OPN->fn_max;
		CH->SLOT[SLOT2].phase += (finc*CH->SLOT[SLOT2].mul) >> 1;

		finc = fc + CH->SLOT[SLOT3].DT[kc];
		if (finc < 0) finc += OPN->fn_max;
		CH->SLOT[SLOT3].phase += (finc*CH->SLOT[SLOT3].mul) >> 1;

		finc = fc + CH->SLOT[SLOT4].DT[kc];
		if (finc < 0) finc += OPN->fn_max;
		CH->SLOT[SLOT4].phase += (finc*CH->SLOT[SLOT4].mul) >> 1;
	}
	else    /* LFO phase modulation  = zero */
	{
			CH->SLOT[SLOT1].phase += CH->SLOT[SLOT1].Incr;
			CH->SLOT[SLOT2].phase += CH->SLOT[SLOT2].Incr;
			CH->SLOT[SLOT3].phase += CH->SLOT[SLOT3].Incr;
			CH->SLOT[SLOT4].phase += CH->SLOT[SLOT4].Incr;
	}
}

static inline void chan_calc(FM_OPN *OPN, FM_CH *CH, int chnum)
{
	unsigned int eg_out;

	uint32_t AM = OPN->LFO_AM >> CH->ams;


	OPN->m2 = OPN->c1 = OPN->c2 = OPN->mem = 0;

	*CH->mem_connect = CH->mem_value;   /* restore delayed sample (MEM) value to m2 or c2 */

	eg_out = volume_calc(&CH->SLOT[SLOT1]);
	{
		int32_t out = CH->op1_out[0] + CH->op1_out[1];
		CH->op1_out[0] = CH->op1_out[1];

		if( !CH->connect1 )
		{
			/* algorithm 5  */
			OPN->mem = OPN->c1 = OPN->c2 = CH->op1_out[0];
		}
		else
		{
			/* other algorithms */
			*CH->connect1 += CH->op1_out[0];
		}

		CH->op1_out[1] = 0;
		if( eg_out < ENV_QUIET )    /* SLOT 1 */
		{
			if (!CH->FB)
				out=0;

			CH->op1_out[1] = op_calc1(CH->SLOT[SLOT1].phase, eg_out, (out<<CH->FB) );
		}
	}

	eg_out = volume_calc(&CH->SLOT[SLOT3]);
	if( eg_out < ENV_QUIET )        /* SLOT 3 */
		*CH->connect3 += op_calc(CH->SLOT[SLOT3].phase, eg_out, OPN->m2);

	eg_out = volume_calc(&CH->SLOT[SLOT2]);
	if( eg_out < ENV_QUIET )        /* SLOT 2 */
		*CH->connect2 += op_calc(CH->SLOT[SLOT2].phase, eg_out, OPN->c1);

	eg_out = volume_calc(&CH->SLOT[SLOT4]);
	if( eg_out < ENV_QUIET )        /* SLOT 4 */
		*CH->connect4 += op_calc(CH->SLOT[SLOT4].phase, eg_out, OPN->c2);


	/* store current MEM */
	CH->mem_value = OPN->mem;

	/* update phase counters AFTER output calculations */
	if(CH->pms)
	{
		/* add support for 3 slot mode */
		if ((OPN->ST.mode & 0xC0) && (chnum == 2))
		{
				update_phase_lfo_slot(OPN, &CH->SLOT[SLOT1], CH->pms, OPN->SL3.block_fnum[1]);
				update_phase_lfo_slot(OPN, &CH->SLOT[SLOT2], CH->pms, OPN->SL3.block_fnum[2]);
				update_phase_lfo_slot(OPN, &CH->SLOT[SLOT3], CH->pms, OPN->SL3.block_fnum[0]);
				update_phase_lfo_slot(OPN, &CH->SLOT[SLOT4], CH->pms, CH->block_fnum);
		}
		else update_phase_lfo_channel(OPN, CH);
	}
	else    /* no LFO phase modulation */
	{
		CH->SLOT[SLOT1].phase += CH->SLOT[SLOT1].Incr;
		CH->SLOT[SLOT2].phase += CH->SLOT[SLOT2].Incr;
		CH->SLOT[SLOT3].phase += CH->SLOT[SLOT3].Incr;
		CH->SLOT[SLOT4].phase += CH->SLOT[SLOT4].Incr;
	}
}

/* update phase increment and envelope generator */
static inline void refresh_fc_eg_slot(FM_OPN *OPN, FM_SLOT *SLOT , int fc , int kc )
{
	int ksr = kc >> SLOT->KSR;

	fc += SLOT->DT[kc];

	/* detects frequency overflow (credits to Nemesis) */
	if (fc < 0) fc += OPN->fn_max;

	/* (frequency) phase increment counter */
	SLOT->Incr = (fc * SLOT->mul) >> 1;

	if( SLOT->ksr != ksr )
	{
		SLOT->ksr = ksr;

		/* calculate envelope generator rates */
		if ((SLOT->ar + SLOT->ksr) < 32+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 = 17*RATE_STEPS;
		}

		SLOT->eg_sh_d1r = eg_rate_shift [SLOT->d1r + SLOT->ksr];
		SLOT->eg_sh_d2r = eg_rate_shift [SLOT->d2r + SLOT->ksr];
		SLOT->eg_sh_rr  = eg_rate_shift [SLOT->rr  + SLOT->ksr];

		SLOT->eg_sel_d1r= eg_rate_select[SLOT->d1r + SLOT->ksr];
		SLOT->eg_sel_d2r= eg_rate_select[SLOT->d2r + SLOT->ksr];
		SLOT->eg_sel_rr = eg_rate_select[SLOT->rr  + SLOT->ksr];
	}
}

/* update phase increment counters */
/* Changed from static inline to static to work around gcc 4.2.1 codegen bug */
static void refresh_fc_eg_chan(FM_OPN *OPN, FM_CH *CH )
{
	if( CH->SLOT[SLOT1].Incr==-1)
	{
		int fc = CH->fc;
		int kc = CH->kcode;
		refresh_fc_eg_slot(OPN, &CH->SLOT[SLOT1] , fc , kc );
		refresh_fc_eg_slot(OPN, &CH->SLOT[SLOT2] , fc , kc );
		refresh_fc_eg_slot(OPN, &CH->SLOT[SLOT3] , fc , kc );
		refresh_fc_eg_slot(OPN, &CH->SLOT[SLOT4] , fc , kc );
	}
}

/* initialize time tables */
static void init_timetables( FM_ST *ST , const uint8_t *dttable )
{
	int i,d;
	double rate;

#if 0
	logerror("FM.C: samplerate=%8i chip clock=%8i  freqbase=%f  \n",
				ST->rate, ST->clock, ST->freqbase );
#endif

	/* DeTune table */
	for (d = 0;d <= 3;d++)
	{
		for (i = 0;i <= 31;i++)
		{
			rate = ((double)dttable[d*32 + i]) * SIN_LEN  * ST->freqbase  * (1<<FREQ_SH) / ((double)(1<<20));
			ST->dt_tab[d][i]   = (int32_t) rate;
			ST->dt_tab[d+4][i] = -ST->dt_tab[d][i];
#if 0
			logerror("FM.C: DT [%2i %2i] = %8x  \n", d, i, ST->dt_tab[d][i] );
#endif
		}
	}

}


static void reset_channels( FM_ST *ST , FM_CH *CH , int num )
{
	int c,s;

	ST->mode   = 0; /* normal mode */
	ST->TA     = 0;
	ST->TAC    = 0;
	ST->TB     = 0;
	ST->TBC    = 0;

	for( c = 0 ; c < num ; c++ )
	{
		CH[c].fc = 0;
		for(s = 0 ; s < 4 ; s++ )
		{
			CH[c].SLOT[s].ssg = 0;
			CH[c].SLOT[s].ssgn = 0;
			CH[c].SLOT[s].state= EG_OFF;
			CH[c].SLOT[s].volume = MAX_ATT_INDEX;
			CH[c].SLOT[s].vol_out= MAX_ATT_INDEX;
		}
	}
}

/* initialize generic tables */
static int init_tables(void)
{
	signed int i,x;
	signed int n;
	double o,m;

	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) */
		n <<= 2;        /* 13 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<13; 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 ];
		}
	#if 0
			logerror("tl %04i", x);
			for (i=0; i<13; i++)
				logerror(", [%02i] %4x", i*2, tl_tab[ x*2 /*+1*/ + i*2*TL_RES_LEN ]);
			logerror("\n");
	#endif
	}
	/*logerror("FM.C: TL_TAB_LEN = %i elements (%i bytes)\n",TL_TAB_LEN, (int)sizeof(tl_tab));*/


	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(2.0);  /* 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 );
		/*logerror("FM.C: sin [%4i]= %4i (tl_tab value=%5i)\n", i, sin_tab[i],tl_tab[sin_tab[i]]);*/
	}

	/*logerror("FM.C: ENV_QUIET= %08x\n",ENV_QUIET );*/


	/* build LFO PM modulation table */
	for(i = 0; i < 8; i++) /* 8 PM depths */
	{
		uint8_t fnum;
		for (fnum=0; fnum<128; fnum++) /* 7 bits meaningful of F-NUMBER */
		{
			uint8_t value;
			uint8_t step;
			uint32_t offset_depth = i;
			uint32_t offset_fnum_bit;
			uint32_t bit_tmp;

			for (step=0; step<8; step++)
			{
				value = 0;
				for (bit_tmp=0; bit_tmp<7; bit_tmp++) /* 7 bits */
				{
					if (fnum & (1<<bit_tmp)) /* only if bit "bit_tmp" is set */
					{
						offset_fnum_bit = bit_tmp * 8;
						value += lfo_pm_output[offset_fnum_bit + offset_depth][step];
					}
				}
				lfo_pm_table[(fnum*32*8) + (i*32) + step   + 0] = value;
				lfo_pm_table[(fnum*32*8) + (i*32) +(step^7)+ 8] = value;
				lfo_pm_table[(fnum*32*8) + (i*32) + step   +16] = -value;
				lfo_pm_table[(fnum*32*8) + (i*32) +(step^7)+24] = -value;
			}
#if 0
			logerror("LFO depth=%1x FNUM=%04x (<<4=%4x): ", i, fnum, fnum<<4);
			for (step=0; step<16; step++) /* dump only positive part of waveforms */
				logerror("%02x ", lfo_pm_table[(fnum*32*8) + (i*32) + step] );
			logerror("\n");
#endif

		}
	}



#ifdef SAVE_SAMPLE
	sample[0]=fopen("sampsum.pcm","wb");
#endif

	return 1;

}



static void FMCloseTable( void )
{
#ifdef SAVE_SAMPLE
	fclose(sample[0]);
#endif
	return;
}


/* CSM Key Controll */
static inline void CSMKeyControll(uint8_t type, FM_CH *CH)
{
	/* all key on then off (only for operators which were OFF!) */
	if (!CH->SLOT[SLOT1].key)
	{
		FM_KEYON(type, CH,SLOT1);
		FM_KEYOFF(CH, SLOT1);
	}
	if (!CH->SLOT[SLOT2].key)
	{
		FM_KEYON(type, CH,SLOT2);
		FM_KEYOFF(CH, SLOT2);
	}
	if (!CH->SLOT[SLOT3].key)
	{
		FM_KEYON(type, CH,SLOT3);
		FM_KEYOFF(CH, SLOT3);
	}
	if (!CH->SLOT[SLOT4].key)
	{
		FM_KEYON(type, CH,SLOT4);
		FM_KEYOFF(CH, SLOT4);
	}
}

#ifdef MAME_EMU_SAVE_H
/* FM channel save , internal state only */
static void FMsave_state_channel(device_t *device,FM_CH *CH,int num_ch)
{
	int slot , ch;

	for(ch=0;ch<num_ch;ch++,CH++)
	{
		/* channel */
		device->save_item(NAME(CH->op1_out), ch);
		device->save_item(NAME(CH->fc), ch);
		/* slots */
		for(slot=0;slot<4;slot++)
		{
			FM_SLOT *SLOT = &CH->SLOT[slot];
			device->save_item(NAME(SLOT->phase), ch * 4 + slot);
			device->save_item(NAME(SLOT->state), ch * 4 + slot);
			device->save_item(NAME(SLOT->volume), ch * 4 + slot);
		}
	}
}

static void FMsave_state_st(device_t *device,FM_ST *ST)
{
#if FM_BUSY_FLAG_SUPPORT
	device->save_item(NAME(ST->busy_expiry_time) );
#endif
	device->save_item(NAME(ST->address) );
	device->save_item(NAME(ST->irq)     );
	device->save_item(NAME(ST->irqmask) );
	device->save_item(NAME(ST->status)  );
	device->save_item(NAME(ST->mode)    );
	device->save_item(NAME(ST->prescaler_sel) );
	device->save_item(NAME(ST->fn_h) );
	device->save_item(NAME(ST->TA)   );
	device->save_item(NAME(ST->TAC)  );
	device->save_item(NAME(ST->TB)  );
	device->save_item(NAME(ST->TBC)  );
}
#endif /* MAME_EMU_SAVE_H */

#if BUILD_OPN



/* prescaler set (and make time tables) */
static void OPNSetPres(FM_OPN *OPN, int pres, int timer_prescaler, int SSGpres)
{
	int i;

	/* frequency base */
	OPN->ST.freqbase = (OPN->ST.rate) ? ((double)OPN->ST.clock / OPN->ST.rate) / pres : 0;

#if 0
	OPN->ST.rate = (double)OPN->ST.clock / pres;
	OPN->ST.freqbase = 1.0;
#endif

	OPN->eg_timer_add  = (uint32_t)((1<<EG_SH) * OPN->ST.freqbase);
	OPN->eg_timer_overflow = ( 3 ) * (1<<EG_SH);


	/* Timer base time */
	OPN->ST.timer_prescaler = timer_prescaler;

	/* SSG part  prescaler set */
	if( SSGpres ) (*OPN->ST.SSG->set_clock)( OPN->ST.device, OPN->ST.clock * 2 / SSGpres );

	/* make time tables */
	init_timetables( &OPN->ST, dt_tab );

	/* there are 2048 FNUMs that can be generated using FNUM/BLK registers
	    but LFO works with one more bit of a precision so we really need 4096 elements */
	/* calculate fnumber -> increment counter table */
	for(i = 0; i < 4096; i++)
	{
		/* freq table for octave 7 */
		/* OPN phase increment counter = 20bit */
		OPN->fn_table[i] = (uint32_t)( (double)i * 32 * OPN->ST.freqbase * (1<<(FREQ_SH-10)) ); /* -10 because chip works with 10.10 fixed point, while we use 16.16 */
#if 0
		logerror("FM.C: fn_table[%4i] = %08x (dec=%8i)\n",
					i, OPN->fn_table[i]>>6,OPN->fn_table[i]>>6 );
#endif
	}

	/* maximal frequency is required for Phase overflow calculation, register size is 17 bits (Nemesis) */
	OPN->fn_max = (uint32_t)( (double)0x20000 * OPN->ST.freqbase * (1<<(FREQ_SH-10)) );

	/* LFO freq. table */
	for(i = 0; i < 8; i++)
	{
		/* Amplitude modulation: 64 output levels (triangle waveform); 1 level lasts for one of "lfo_samples_per_step" samples */
		/* Phase modulation: one entry from lfo_pm_output lasts for one of 4 * "lfo_samples_per_step" samples  */
		OPN->lfo_freq[i] = (uint32_t)((1.0 / lfo_samples_per_step[i]) * (1<<LFO_SH) * OPN->ST.freqbase);
#if 0
		logerror("FM.C: lfo_freq[%i] = %08x (dec=%8i)\n",
					i, OPN->lfo_freq[i],OPN->lfo_freq[i] );
#endif
	}
}



/* write a OPN mode register 0x20-0x2f */
static void OPNWriteMode(FM_OPN *OPN, int r, int v)
{
	uint8_t c;
	FM_CH *CH;

	switch(r)
	{
	case 0x21:  /* Test */
		break;
	case 0x22:  /* LFO FREQ (YM2608/YM2610/YM2610B/YM2612) */
		if( OPN->type & TYPE_LFOPAN )
		{
			if (v&0x08) /* LFO enabled ? */
			{
				OPN->lfo_inc = OPN->lfo_freq[v&7];
			}
			else
			{
				OPN->lfo_inc = 0;
			}
		}
		break;
	case 0x24:  /* timer A High 8*/
		OPN->ST.TA = (OPN->ST.TA & 0x03)|(((int)v)<<2);
		break;
	case 0x25:  /* timer A Low 2*/
		OPN->ST.TA = (OPN->ST.TA & 0x3fc)|(v&3);
		break;
	case 0x26:  /* timer B */
		OPN->ST.TB = v;
		break;
	case 0x27:  /* mode, timer control */
		set_timers( &(OPN->ST),OPN->ST.device,v );
		break;
	case 0x28:  /* key on / off */
		c = v & 0x03;
		if( c == 3 ) break;
		if( (v&0x04) && (OPN->type & TYPE_6CH) ) c+=3;
		CH = OPN->P_CH;
		CH = &CH[c];
		if(v&0x10) FM_KEYON(OPN->type,CH,SLOT1); else FM_KEYOFF(CH,SLOT1);
		if(v&0x20) FM_KEYON(OPN->type,CH,SLOT2); else FM_KEYOFF(CH,SLOT2);
		if(v&0x40) FM_KEYON(OPN->type,CH,SLOT3); else FM_KEYOFF(CH,SLOT3);
		if(v&0x80) FM_KEYON(OPN->type,CH,SLOT4); else FM_KEYOFF(CH,SLOT4);
		break;
	}
}

/* write a OPN register (0x30-0xff) */
static void OPNWriteReg(FM_OPN *OPN, int r, int v)
{
	FM_CH *CH;
	FM_SLOT *SLOT;

	uint8_t c = OPN_CHAN(r);

	if (c == 3) return; /* 0xX3,0xX7,0xXB,0xXF */

	if (r >= 0x100) c+=3;

	CH = OPN->P_CH;
	CH = &CH[c];

	SLOT = &(CH->SLOT[OPN_SLOT(r)]);

	switch( r & 0xf0 )
	{
	case 0x30:  /* DET , MUL */
		set_det_mul(&OPN->ST,CH,SLOT,v);
		break;

	case 0x40:  /* TL */
		set_tl(CH,SLOT,v);
		break;

	case 0x50:  /* KS, AR */
		set_ar_ksr(OPN->type,CH,SLOT,v);
		break;

	case 0x60:  /* bit7 = AM ENABLE, DR */
		set_dr(OPN->type, SLOT,v);

		if(OPN->type & TYPE_LFOPAN) /* YM2608/2610/2610B/2612 */
		{
			SLOT->AMmask = (v&0x80) ? ~0 : 0;
		}
		break;

	case 0x70:  /*     SR */
		set_sr(OPN->type,SLOT,v);
		break;

	case 0x80:  /* SL, RR */
		set_sl_rr(OPN->type,SLOT,v);
		break;

	case 0x90:  /* SSG-EG */
		SLOT->ssg  =  v&0x0f;
		SLOT->ssgn = (v&0x04)>>1; /* bit 1 in ssgn = attack */

		/* SSG-EG envelope shapes :

		E AtAlH
		1 0 0 0  \\\\

		1 0 0 1  \___

		1 0 1 0  \/\/
		          ___
		1 0 1 1  \

		1 1 0 0  ////
		          ___
		1 1 0 1  /

		1 1 1 0  /\/\

		1 1 1 1  /___


		E = SSG-EG enable


		The shapes are generated using Attack, Decay and Sustain phases.

		Each single character in the diagrams above represents this whole
		sequence:

		- when KEY-ON = 1, normal Attack phase is generated (*without* any
		  difference when compared to normal mode),

		- later, when envelope level reaches minimum level (max volume),
		  the EG switches to Decay phase (which works with bigger steps
		  when compared to normal mode - see below),

		- later when envelope level passes the SL level,
		  the EG swithes to Sustain phase (which works with bigger steps
		  when compared to normal mode - see below),

		- finally when envelope level reaches maximum level (min volume),
		  the EG switches to Attack phase again (depends on actual waveform).

		Important is that when switch to Attack phase occurs, the phase counter
		of that operator will be zeroed-out (as in normal KEY-ON) but not always.
		(I havent found the rule for that - perhaps only when the output level is low)

		The difference (when compared to normal Envelope Generator mode) is
		that the resolution in Decay and Sustain phases is 4 times lower;
		this results in only 256 steps instead of normal 1024.
		In other words:
		when SSG-EG is disabled, the step inside of the EG is one,
		when SSG-EG is enabled, the step is four (in Decay and Sustain phases).

		Times between the level changes are the same in both modes.


		Important:
		Decay 1 Level (so called SL) is compared to actual SSG-EG output, so
		it is the same in both SSG and no-SSG modes, with this exception:

		when the SSG-EG is enabled and is generating raising levels
		(when the EG output is inverted) the SL will be found at wrong level !!!
		For example, when SL=02:
		    0 -6 = -6dB in non-inverted EG output
		    96-6 = -90dB in inverted EG output
		Which means that EG compares its level to SL as usual, and that the
		output is simply inverted afterall.


		The Yamaha's manuals say that AR should be set to 0x1f (max speed).
		That is not necessary, but then EG will be generating Attack phase.

		*/


		break;

	case 0xa0:
		switch( OPN_SLOT(r) )
		{
		case 0:     /* 0xa0-0xa2 : FNUM1 */
			{
				uint32_t fn = (((uint32_t)( (OPN->ST.fn_h)&7))<<8) + v;
				uint8_t blk = OPN->ST.fn_h>>3;
				/* keyscale code */
				CH->kcode = (blk<<2) | opn_fktable[fn >> 7];
				/* phase increment counter */
				CH->fc = OPN->fn_table[fn*2]>>(7-blk);

				/* store fnum in clear form for LFO PM calculations */
				CH->block_fnum = (blk<<11) | fn;

				CH->SLOT[SLOT1].Incr=-1;
			}
			break;
		case 1:     /* 0xa4-0xa6 : FNUM2,BLK */
			OPN->ST.fn_h = v&0x3f;
			break;
		case 2:     /* 0xa8-0xaa : 3CH FNUM1 */
			if(r < 0x100)
			{
				uint32_t fn = (((uint32_t)(OPN->SL3.fn_h&7))<<8) + v;
				uint8_t blk = OPN->SL3.fn_h>>3;
				/* keyscale code */
				OPN->SL3.kcode[c]= (blk<<2) | opn_fktable[fn >> 7];
				/* phase increment counter */
				OPN->SL3.fc[c] = OPN->fn_table[fn*2]>>(7-blk);
				OPN->SL3.block_fnum[c] = (blk<<11) | fn;
				(OPN->P_CH)[2].SLOT[SLOT1].Incr=-1;
			}
			break;
		case 3:     /* 0xac-0xae : 3CH FNUM2,BLK */
			if(r < 0x100)
				OPN->SL3.fn_h = v&0x3f;
			break;
		}
		break;

	case 0xb0:
		switch( OPN_SLOT(r) )
		{
		case 0:     /* 0xb0-0xb2 : FB,ALGO */
			{
				int feedback = (v>>3)&7;
				CH->ALGO = v&7;
				CH->FB   = feedback ? feedback+6 : 0;
				setup_connection( OPN, CH, c );
			}
			break;
		case 1:     /* 0xb4-0xb6 : L , R , AMS , PMS (YM2612/YM2610B/YM2610/YM2608) */
			if( OPN->type & TYPE_LFOPAN)
			{
				/* b0-2 PMS */
				CH->pms = (v & 7) * 32; /* CH->pms = PM depth * 32 (index in lfo_pm_table) */

				/* b4-5 AMS */
				CH->ams = lfo_ams_depth_shift[(v>>4) & 0x03];

				/* PAN :  b7 = L, b6 = R */
				OPN->pan[ c*2   ] = (v & 0x80) ? ~0 : 0;
				OPN->pan[ c*2+1 ] = (v & 0x40) ? ~0 : 0;

			}
			break;
		}
		break;
	}
}

#endif /* BUILD_OPN */

#if BUILD_OPN_PRESCALER
/*
  prescaler circuit (best guess to verified chip behaviour)

               +--------------+  +-sel2-+
               |              +--|in20  |
         +---+ |  +-sel1-+       |      |
M-CLK -+-|1/2|-+--|in10  | +---+ |   out|--INT_CLOCK
       | +---+    |   out|-|1/3|-|in21  |
       +----------|in11  | +---+ +------+
                  +------+

reg.2d : sel2 = in21 (select sel2)
reg.2e : sel1 = in11 (select sel1)
reg.2f : sel1 = in10 , sel2 = in20 (clear selector)
reset  : sel1 = in11 , sel2 = in21 (clear both)

*/
static void OPNPrescaler_w(FM_OPN *OPN , int addr, int pre_divider)
{
	static const int opn_pres[4] = { 2*12 , 2*12 , 6*12 , 3*12 };
	static const int ssg_pres[4] = { 1    ,    1 ,    4 ,    2 };
	int sel;

	switch(addr)
	{
	case 0:     /* when reset */
		OPN->ST.prescaler_sel = 2;
		break;
	case 1:     /* when postload */
		break;
	case 0x2d:  /* divider sel : select 1/1 for 1/3line    */
		OPN->ST.prescaler_sel |= 0x02;
		break;
	case 0x2e:  /* divider sel , select 1/3line for output */
		OPN->ST.prescaler_sel |= 0x01;
		break;
	case 0x2f:  /* divider sel , clear both selector to 1/2,1/2 */
		OPN->ST.prescaler_sel = 0;
		break;
	}
	sel = OPN->ST.prescaler_sel & 3;
	/* update prescaler */
	OPNSetPres( OPN,    opn_pres[sel]*pre_divider,
						opn_pres[sel]*pre_divider,
						ssg_pres[sel]*pre_divider );
}
#endif /* BUILD_OPN_PRESCALER */

#if BUILD_YM2203
/*****************************************************************************/
/*      YM2203 local section                                                 */
/*****************************************************************************/

/* here's the virtual YM2203(OPN) */
namespace {
struct ym2203_state
{
	uint8_t REGS[256];        /* registers         */
	FM_OPN OPN;             /* OPN state         */
	FM_CH CH[3];            /* channel state     */
};
} // anonymous namespace

/* Generate samples for one of the YM2203s */
void ym2203_update_one(void *chip, FMSAMPLE *buffer, int length)
{
	ym2203_state *F2203 = (ym2203_state *)chip;
	FM_OPN *OPN =   &F2203->OPN;
	int i;
	FMSAMPLE *buf = buffer;
	FM_CH   *cch[3];

	cch[0]   = &F2203->CH[0];
	cch[1]   = &F2203->CH[1];
	cch[2]   = &F2203->CH[2];


	/* refresh PG and EG */
	refresh_fc_eg_chan( OPN, cch[0] );
	refresh_fc_eg_chan( OPN, cch[1] );
	if( (F2203->OPN.ST.mode & 0xc0) )
	{
		/* 3SLOT MODE */
		if( cch[2]->SLOT[SLOT1].Incr==-1)
		{
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT1] , OPN->SL3.fc[1] , OPN->SL3.kcode[1] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT2] , OPN->SL3.fc[2] , OPN->SL3.kcode[2] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT3] , OPN->SL3.fc[0] , OPN->SL3.kcode[0] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT4] , cch[2]->fc , cch[2]->kcode );
		}
	}
	else
		refresh_fc_eg_chan( OPN, cch[2] );


	/* YM2203 doesn't have LFO so we must keep these globals at 0 level */
	OPN->LFO_AM = 0;
	OPN->LFO_PM = 0;

	/* buffering */
	for (i=0; i < length ; i++)
	{
		/* clear outputs */
		OPN->out_fm[0] = 0;
		OPN->out_fm[1] = 0;
		OPN->out_fm[2] = 0;

		/* advance envelope generator */
		OPN->eg_timer += OPN->eg_timer_add;
		while (OPN->eg_timer >= OPN->eg_timer_overflow)
		{
			OPN->eg_timer -= OPN->eg_timer_overflow;
			OPN->eg_cnt++;

			advance_eg_channel(OPN, &cch[0]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[1]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[2]->SLOT[SLOT1]);
		}

		/* calculate FM */
		chan_calc(OPN, cch[0], 0 );
		chan_calc(OPN, cch[1], 1 );
		chan_calc(OPN, cch[2], 2 );

		/* buffering */
		{
			int lt;

			lt = OPN->out_fm[0] + OPN->out_fm[1] + OPN->out_fm[2];

			lt >>= FINAL_SH;

			Limit( lt , MAXOUT, MINOUT );

			#ifdef SAVE_SAMPLE
				SAVE_ALL_CHANNELS
			#endif

			/* buffering */
			buf[i] = lt;
		}

		/* timer A control */
		INTERNAL_TIMER_A( &F2203->OPN.ST , cch[2] )
	}
	INTERNAL_TIMER_B(&F2203->OPN.ST,length)
}

/* ---------- reset one of chip ---------- */
void ym2203_reset_chip(void *chip)
{
	int i;
	ym2203_state *F2203 = (ym2203_state *)chip;
	FM_OPN *OPN = &F2203->OPN;

	/* Reset Prescaler */
	OPNPrescaler_w(OPN, 0 , 1 );
	/* reset SSG section */
	(*OPN->ST.SSG->reset)(OPN->ST.device);
	/* status clear */
	FM_IRQMASK_SET(&OPN->ST,0x03);
	FM_BUSY_CLEAR(&OPN->ST);
	OPNWriteMode(OPN,0x27,0x30); /* mode 0 , timer reset */

	OPN->eg_timer = 0;
	OPN->eg_cnt   = 0;

	FM_STATUS_RESET(&OPN->ST, 0xff);

	reset_channels( &OPN->ST , F2203->CH , 3 );
	/* reset OPerator paramater */
	for(i = 0xb2 ; i >= 0x30 ; i-- ) OPNWriteReg(OPN,i,0);
	for(i = 0x26 ; i >= 0x20 ; i-- ) OPNWriteReg(OPN,i,0);
}

#ifdef MAME_EMU_SAVE_H
void ym2203_postload(void *chip)
{
	if (chip)
	{
		ym2203_state *F2203 = (ym2203_state *)chip;
		int r;

		/* prescaler */
		OPNPrescaler_w(&F2203->OPN,1,1);

		/* SSG registers */
		for(r=0;r<16;r++)
		{
			(*F2203->OPN.ST.SSG->write)(F2203->OPN.ST.device,0,r);
			(*F2203->OPN.ST.SSG->write)(F2203->OPN.ST.device,1,F2203->REGS[r]);
		}

		/* OPN registers */
		/* DT / MULTI , TL , KS / AR , AMON / DR , SR , SL / RR , SSG-EG */
		for(r=0x30;r<0x9e;r++)
			if((r&3) != 3)
				OPNWriteReg(&F2203->OPN,r,F2203->REGS[r]);
		/* FB / CONNECT , L / R / AMS / PMS */
		for(r=0xb0;r<0xb6;r++)
			if((r&3) != 3)
				OPNWriteReg(&F2203->OPN,r,F2203->REGS[r]);

		/* channels */
		/*FM_channel_postload(F2203->CH,3);*/
	}
}

static void YM2203_save_state(ym2203_state *F2203, device_t *device)
{
	device->save_item(NAME(F2203->REGS));
	FMsave_state_st(device,&F2203->OPN.ST);
	FMsave_state_channel(device,F2203->CH,3);
	/* 3slots */
	device->save_item (NAME(F2203->OPN.SL3.fc));
	device->save_item  (NAME(F2203->OPN.SL3.fn_h));
	device->save_item  (NAME(F2203->OPN.SL3.kcode));
}
#endif /* MAME_EMU_SAVE_H */

/* ----------  Initialize YM2203 emulator(s) ----------
   'num' is the number of virtual YM2203s to allocate
   'clock' is the chip clock in Hz
   'rate' is sampling rate
*/
void * ym2203_init(device_t *device, int clock, int rate, FM_TIMERHANDLER timer_handler,FM_IRQHANDLER IRQHandler, const ssg_callbacks *ssg)
{
	ym2203_state *F2203;

	/* allocate ym2203 state space */
	F2203 = new ym2203_state;
	memset(F2203, 0, sizeof(*F2203));

	if( !init_tables() )
	{
		delete F2203;
		return nullptr;
	}

	F2203->OPN.type = TYPE_YM2203;
	F2203->OPN.P_CH = F2203->CH;
	F2203->OPN.ST.device = device;
	F2203->OPN.ST.clock = clock;
	F2203->OPN.ST.rate = rate;

	F2203->OPN.ST.timer_handler = timer_handler;
	F2203->OPN.ST.IRQ_Handler   = IRQHandler;
	F2203->OPN.ST.SSG           = ssg;

	for (unsigned i = 0; i < 3; i++)
	{
		F2203->CH[i].pan_volume_l = 46340;
		F2203->CH[i].pan_volume_r = 46340;
	}

#ifdef MAME_EMU_SAVE_H
	YM2203_save_state(F2203, device);
#endif
	return F2203;
}

void ym2203_clock_changed(void *chip, int clock, int rate)
{
	ym2203_state *FM2203 = (ym2203_state *)chip;

	FM2203->OPN.ST.clock = clock;
	FM2203->OPN.ST.rate = rate;
}

/* shut down emulator */
void ym2203_shutdown(void *chip)
{
	ym2203_state *FM2203 = (ym2203_state *)chip;

	FMCloseTable();
	delete FM2203;
}

/* YM2203 I/O interface */
int ym2203_write(void *chip,int a,uint8_t v)
{
	ym2203_state *F2203 = (ym2203_state *)chip;
	FM_OPN *OPN = &F2203->OPN;

	if( !(a&1) )
	{   /* address port */
		OPN->ST.address = (v &= 0xff);

		/* Write register to SSG emulator */
		if( v < 16 ) (*OPN->ST.SSG->write)(OPN->ST.device,0,v);

		/* prescaler select : 2d,2e,2f  */
		if( v >= 0x2d && v <= 0x2f )
			OPNPrescaler_w(OPN , v , 1);
	}
	else
	{   /* data port */
		int addr = OPN->ST.address;
		F2203->REGS[addr] = v;
		switch( addr & 0xf0 )
		{
		case 0x00:  /* 0x00-0x0f : SSG section */
			/* Write data to SSG emulator */
			(*OPN->ST.SSG->write)(OPN->ST.device,a,v);
			break;
		case 0x20:  /* 0x20-0x2f : Mode section */
			ym2203_device::update_request(OPN->ST.device);
			/* write register */
			OPNWriteMode(OPN,addr,v);
			break;
		default:    /* 0x30-0xff : OPN section */
			ym2203_device::update_request(OPN->ST.device);
			/* write register */
			OPNWriteReg(OPN,addr,v);
		}
		FM_BUSY_SET(&OPN->ST,1);
	}
	return OPN->ST.irq;
}

uint8_t ym2203_read(void *chip,int a)
{
	ym2203_state *F2203 = (ym2203_state *)chip;
	int addr = F2203->OPN.ST.address;
	uint8_t ret = 0;

	if( !(a&1) )
	{   /* status port */
		ret = FM_STATUS_FLAG(&F2203->OPN.ST);
	}
	else
	{   /* data port (only SSG) */
		if( addr < 16 ) ret = (*F2203->OPN.ST.SSG->read)(F2203->OPN.ST.device);
	}
	return ret;
}

int ym2203_timer_over(void *chip,int c)
{
	ym2203_state *F2203 = (ym2203_state *)chip;

	if( c )
	{   /* Timer B */
		TimerBOver( &(F2203->OPN.ST) );
	}
	else
	{   /* Timer A */
		ym2203_device::update_request(F2203->OPN.ST.device);
		/* timer update */
		TimerAOver( &(F2203->OPN.ST) );
		/* CSM mode key,TL control */
		if( F2203->OPN.ST.mode & 0x80 )
		{   /* CSM mode auto key on */
			CSMKeyControll( F2203->OPN.type, &(F2203->CH[2]) );
		}
	}
	return F2203->OPN.ST.irq;
}
#endif /* BUILD_YM2203 */



#if (BUILD_YM2608||BUILD_YM2610||BUILD_YM2610B)

namespace {
/**** YM2610 ADPCM defines ****/
CONSTEXPR unsigned ADPCM_SHIFT          = 16;  /* frequency step rate   */
CONSTEXPR unsigned ADPCMA_ADDRESS_SHIFT = 8;   /* adpcm A address shift */

/* speedup purposes only */
static int jedi_table[ 49*16 ];

/* ADPCM type A channel struct */
struct ADPCM_CH
{
	uint8_t       flag;           /* port state               */
	uint8_t       flagMask;       /* arrived flag mask        */
	uint8_t       now_data;       /* current ROM data         */
	uint32_t      now_addr;       /* current ROM address      */
	uint32_t      now_step;
	uint32_t      step;
	uint32_t      start;          /* sample data start address*/
	uint32_t      end;            /* sample data end address  */
	uint8_t       IL;             /* Instrument Level         */
	int32_t       adpcm_acc;      /* accumulator              */
	int32_t       adpcm_step;     /* step                     */
	int32_t       adpcm_out;      /* (speedup) hiro-shi!!     */
	int8_t        vol_mul;        /* volume in "0.75dB" steps */
	uint8_t       vol_shift;      /* volume in "-6dB" steps   */
	int32_t       *pan;           /* &out_adpcm[OPN_xxxx]     */
};

/* here's the virtual YM2610 */
struct ym2610_state
{
	uint8_t       REGS[512];          /* registers            */
	FM_OPN      OPN;                /* OPN state            */
	FM_CH       CH[6];              /* channel state        */
	uint8_t       addr_A1;            /* address line A1      */

	/* ADPCM-A unit */
	FM_READBYTE   read_byte;
	uint8_t       adpcmTL;            /* adpcmA total level   */
	ADPCM_CH    adpcm[6];           /* adpcm channels       */
	uint32_t      adpcmreg[0x30];     /* registers            */
	uint8_t       adpcm_arrivedEndAddress;
	YM_DELTAT   deltaT;             /* Delta-T ADPCM unit   */

	uint8_t       flagmask;           /* YM2608 only */
	uint8_t       irqmask;            /* YM2608 only */

	device_t    *device;

	/* different from the usual ADPCM table */
	//static CONSTEXPR int step_inc[8] = { -1*16, -1*16, -1*16, -1*16, 2*16, 5*16, 7*16, 9*16 };
	static int step_inc[8];

	/* ADPCM A (Non control type) : calculate one channel output */
	inline void ADPCMA_calc_chan( ADPCM_CH *ch )
	{
		uint32_t step;
		uint8_t  data;


		ch->now_step += ch->step;
		if ( ch->now_step >= uint32_t(1<<ADPCM_SHIFT) )
		{
			step = ch->now_step >> ADPCM_SHIFT;
			ch->now_step &= (1<<ADPCM_SHIFT)-1;
			do{
				/* end check */
				/* 11-06-2001 JB: corrected comparison. Was > instead of == */
				/* YM2610 checks lower 20 bits only, the 4 MSB bits are sample bank */
				/* Here we use 1<<21 to compensate for nibble calculations */

				if (   (ch->now_addr & ((1<<21)-1)) == ((ch->end<<1) & ((1<<21)-1))    )
				{
					ch->flag = 0;
					adpcm_arrivedEndAddress |= ch->flagMask;
					return;
				}
#if 0
				if ( ch->now_addr > (pcmsizeA<<1) )
				{
					LOG(LOG_WAR,("YM2610: Attempting to play past adpcm rom size!\n" ));
					return;
				}
#endif
				if ( ch->now_addr&1 )
					data = ch->now_data & 0x0f;
				else
				{
					ch->now_data = read_byte(device, ch->now_addr>>1);
					data = (ch->now_data >> 4) & 0x0f;
				}

				ch->now_addr++;

				ch->adpcm_acc += jedi_table[ch->adpcm_step + data];

				/* extend 12-bit signed int */
				if (ch->adpcm_acc & ~0x7ff)
					ch->adpcm_acc |= ~0xfff;
				else
					ch->adpcm_acc &= 0xfff;

				ch->adpcm_step += step_inc[data & 7];
				Limit( ch->adpcm_step, 48*16, 0*16 );

			}while(--step);

			/* calc pcm * volume data */
			ch->adpcm_out = ((ch->adpcm_acc * ch->vol_mul) >> ch->vol_shift) & ~3;  /* multiply, shift and mask out 2 LSB bits */
		}

		/* output for work of output channels (out_adpcm[OPNxxxx])*/
		*(ch->pan) += ch->adpcm_out;
	}

	/* ADPCM type A Write */
	void FM_ADPCMAWrite(int r,int v)
	{
		uint8_t c = r&0x07;

		adpcmreg[r] = v&0xff; /* stock data */
		switch( r )
		{
		case 0x00: /* DM,--,C5,C4,C3,C2,C1,C0 */
			if( !(v&0x80) )
			{
				/* KEY ON */
				for( c = 0; c < 6; c++ )
				{
					if( (v>>c)&1 )
					{
						/**** start adpcm ****/
						adpcm[c].step      = (uint32_t)((float)(1<<ADPCM_SHIFT)*((float)OPN.ST.freqbase)/3.0f);
						adpcm[c].now_addr  = adpcm[c].start<<1;
						adpcm[c].now_step  = 0;
						adpcm[c].adpcm_acc = 0;
						adpcm[c].adpcm_step= 0;
						adpcm[c].adpcm_out = 0;
						adpcm[c].flag      = 1;
					}
				}
			}
			else
			{
				/* KEY OFF */
				for( c = 0; c < 6; c++ )
					if( (v>>c)&1 )
						adpcm[c].flag = 0;
			}
			break;
		case 0x01:  /* B0-5 = TL */
			adpcmTL = (v & 0x3f) ^ 0x3f;
			for( c = 0; c < 6; c++ )
			{
				int volume = adpcmTL + adpcm[c].IL;

				if ( volume >= 63 ) /* This is correct, 63 = quiet */
				{
					adpcm[c].vol_mul   = 0;
					adpcm[c].vol_shift = 0;
				}
				else
				{
					adpcm[c].vol_mul   = 15 - (volume & 7);     /* so called 0.75 dB */
					adpcm[c].vol_shift =  1 + (volume >> 3);    /* Yamaha engineers used the approximation: each -6 dB is close to divide by two (shift right) */
				}

				/* calc pcm * volume data */
				adpcm[c].adpcm_out = ((adpcm[c].adpcm_acc * adpcm[c].vol_mul) >> adpcm[c].vol_shift) & ~3;  /* multiply, shift and mask out low 2 bits */
			}
			break;
		default:
			c = r&0x07;
			if( c >= 0x06 ) return;
			switch( r&0x38 )
			{
			case 0x08:  /* B7=L,B6=R, B4-0=IL */
			{
				int volume;

				adpcm[c].IL = (v & 0x1f) ^ 0x1f;

				volume = adpcmTL + adpcm[c].IL;

				if ( volume >= 63 ) /* This is correct, 63 = quiet */
				{
					adpcm[c].vol_mul   = 0;
					adpcm[c].vol_shift = 0;
				}
				else
				{
					adpcm[c].vol_mul   = 15 - (volume & 7);     /* so called 0.75 dB */
					adpcm[c].vol_shift =  1 + (volume >> 3);    /* Yamaha engineers used the approximation: each -6 dB is close to divide by two (shift right) */
				}

				adpcm[c].pan    = &OPN.out_adpcm[(v>>6)&0x03];

				/* calc pcm * volume data */
				adpcm[c].adpcm_out = ((adpcm[c].adpcm_acc * adpcm[c].vol_mul) >> adpcm[c].vol_shift) & ~3;  /* multiply, shift and mask out low 2 bits */
			}
				break;
			case 0x10:
			case 0x18:
				adpcm[c].start  = ( (adpcmreg[0x18 + c]*0x0100 | adpcmreg[0x10 + c]) << ADPCMA_ADDRESS_SHIFT);
				break;
			case 0x20:
			case 0x28:
				adpcm[c].end    = ( (adpcmreg[0x28 + c]*0x0100 | adpcmreg[0x20 + c]) << ADPCMA_ADDRESS_SHIFT);
				adpcm[c].end   += (1<<ADPCMA_ADDRESS_SHIFT) - 1;
				break;
			}
		}
	}

};

int ym2610_state::step_inc[8] = { -1*16, -1*16, -1*16, -1*16, 2*16, 5*16, 7*16, 9*16 };

/* here is the virtual YM2608 */
typedef ym2610_state ym2608_state;


/* Algorithm and tables verified on real YM2608 and YM2610 */

/* usual ADPCM table (16 * 1.1^N) */
CONSTEXPR int steps[49] =
{
		16,  17,   19,   21,   23,   25,   28,
		31,  34,   37,   41,   45,   50,   55,
		60,  66,   73,   80,   88,   97,  107,
	118, 130,  143,  157,  173,  190,  209,
	230, 253,  279,  307,  337,  371,  408,
	449, 494,  544,  598,  658,  724,  796,
	876, 963, 1060, 1166, 1282, 1411, 1552
};


void Init_ADPCMATable()
{
	int step, nib;

	for (step = 0; step < 49; step++)
	{
		/* loop over all nibbles and compute the difference */
		for (nib = 0; nib < 16; nib++)
		{
			int value = (2*(nib & 0x07) + 1) * steps[step] / 8;
			jedi_table[step*16 + nib] = (nib&0x08) ? -value : value;
		}
	}
}

#ifdef MAME_EMU_SAVE_H
/* FM channel save , internal state only */
void FMsave_state_adpcma(device_t *device,ADPCM_CH *adpcm)
{
	int ch;

	for(ch=0;ch<6;ch++,adpcm++)
	{
		device->save_item(NAME(adpcm->flag), ch);
		device->save_item(NAME(adpcm->now_data), ch);
		device->save_item(NAME(adpcm->now_addr), ch);
		device->save_item(NAME(adpcm->now_step), ch);
		device->save_item(NAME(adpcm->adpcm_acc), ch);
		device->save_item(NAME(adpcm->adpcm_step), ch);
		device->save_item(NAME(adpcm->adpcm_out), ch);
	}
}
#endif /* MAME_EMU_SAVE_H */
} // anonymous namespace

#endif /* (BUILD_YM2608||BUILD_YM2610||BUILD_YM2610B) */


#if BUILD_YM2608
/*****************************************************************************/
/*      YM2608 local section                                                 */
/*****************************************************************************/



static const unsigned int YM2608_ADPCM_ROM_addr[2*6] = {
0x0000, 0x01bf, /* bass drum  */
0x01c0, 0x043f, /* snare drum */
0x0440, 0x1b7f, /* top cymbal */
0x1b80, 0x1cff, /* high hat */
0x1d00, 0x1f7f, /* tom tom  */
0x1f80, 0x1fff  /* rim shot */
};


/* flag enable control 0x110 */
static inline void YM2608IRQFlagWrite(FM_OPN *OPN, ym2608_state *F2608, int v)
{
	if( v & 0x80 )
	{   /* Reset IRQ flag */
		FM_STATUS_RESET(&OPN->ST, 0xf7); /* don't touch BUFRDY flag otherwise we'd have to call ymdeltat module to set the flag back */
	}
	else
	{   /* Set status flag mask */
		F2608->flagmask = (~(v&0x1f));
		FM_IRQMASK_SET(&OPN->ST, (F2608->irqmask & F2608->flagmask) );
	}
}

/* compatible mode & IRQ enable control 0x29 */
static inline void YM2608IRQMaskWrite(FM_OPN *OPN, ym2608_state *F2608, int v)
{
	/* SCH,xx,xxx,EN_ZERO,EN_BRDY,EN_EOS,EN_TB,EN_TA */

	/* extend 3ch. enable/disable */
	if(v&0x80)
		OPN->type |= TYPE_6CH;  /* OPNA mode - 6 FM channels */
	else
		OPN->type &= ~TYPE_6CH; /* OPN mode - 3 FM channels */

	/* IRQ MASK store and set */
	F2608->irqmask = v&0x1f;
	FM_IRQMASK_SET(&OPN->ST, (F2608->irqmask & F2608->flagmask) );
}

/* Generate samples for one of the YM2608s */
void ym2608_update_one(void *chip, FMSAMPLE **buffer, int length)
{
	ym2608_state *F2608 = (ym2608_state *)chip;
	FM_OPN *OPN   = &F2608->OPN;
	YM_DELTAT *DELTAT = &F2608->deltaT;
	int i,j;
	FMSAMPLE  *bufL,*bufR;
	FM_CH   *cch[6];
	int32_t *out_fm = OPN->out_fm;

	/* set bufer */
	bufL = buffer[0];
	bufR = buffer[1];

	cch[0]   = &F2608->CH[0];
	cch[1]   = &F2608->CH[1];
	cch[2]   = &F2608->CH[2];
	cch[3]   = &F2608->CH[3];
	cch[4]   = &F2608->CH[4];
	cch[5]   = &F2608->CH[5];

	/* refresh PG and EG */
	refresh_fc_eg_chan( OPN, cch[0] );
	refresh_fc_eg_chan( OPN, cch[1] );
	if( (OPN->ST.mode & 0xc0) )
	{
		/* 3SLOT MODE */
		if( cch[2]->SLOT[SLOT1].Incr==-1)
		{
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT1] , OPN->SL3.fc[1] , OPN->SL3.kcode[1] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT2] , OPN->SL3.fc[2] , OPN->SL3.kcode[2] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT3] , OPN->SL3.fc[0] , OPN->SL3.kcode[0] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT4] , cch[2]->fc , cch[2]->kcode );
		}
	}
	else
		refresh_fc_eg_chan( OPN, cch[2] );
	refresh_fc_eg_chan( OPN, cch[3] );
	refresh_fc_eg_chan( OPN, cch[4] );
	refresh_fc_eg_chan( OPN, cch[5] );


	/* buffering */
	for(i=0; i < length ; i++)
	{
		advance_lfo(OPN);

		/* clear output acc. */
		OPN->out_adpcm[OUTD_LEFT] = OPN->out_adpcm[OUTD_RIGHT] = OPN->out_adpcm[OUTD_CENTER] = 0;
		OPN->out_delta[OUTD_LEFT] = OPN->out_delta[OUTD_RIGHT] = OPN->out_delta[OUTD_CENTER] = 0;
		/* clear outputs */
		out_fm[0] = 0;
		out_fm[1] = 0;
		out_fm[2] = 0;
		out_fm[3] = 0;
		out_fm[4] = 0;
		out_fm[5] = 0;

		/* calculate FM */
		chan_calc(OPN, cch[0], 0 );
		chan_calc(OPN, cch[1], 1 );
		chan_calc(OPN, cch[2], 2 );
		chan_calc(OPN, cch[3], 3 );
		chan_calc(OPN, cch[4], 4 );
		chan_calc(OPN, cch[5], 5 );

		/* deltaT ADPCM */
		if( DELTAT->portstate&0x80 )
			DELTAT->ADPCM_CALC();

		/* ADPCMA */
		for( j = 0; j < 6; j++ )
		{
			if( F2608->adpcm[j].flag )
				F2608->ADPCMA_calc_chan( &F2608->adpcm[j]);
		}

		/* advance envelope generator */
		OPN->eg_timer += OPN->eg_timer_add;
		while (OPN->eg_timer >= OPN->eg_timer_overflow)
		{
			OPN->eg_timer -= OPN->eg_timer_overflow;
			OPN->eg_cnt++;

			advance_eg_channel(OPN, &cch[0]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[1]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[2]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[3]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[4]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[5]->SLOT[SLOT1]);
		}

		/* buffering */
		{
			int lt,rt;

			lt =  OPN->out_adpcm[OUTD_LEFT]  + OPN->out_adpcm[OUTD_CENTER];
			rt =  OPN->out_adpcm[OUTD_RIGHT] + OPN->out_adpcm[OUTD_CENTER];
			lt += (OPN->out_delta[OUTD_LEFT]  + OPN->out_delta[OUTD_CENTER])>>9;
			rt += (OPN->out_delta[OUTD_RIGHT] + OPN->out_delta[OUTD_CENTER])>>9;

			/* libOPNMIDI: 6-channels mixing  */
#define PANLAW_L(ch, chpan) (((out_fm[ch]>>1) * cch[ch]->pan_volume_l / 65535) & OPN->pan[chpan]);
#define PANLAW_R(ch, chpan) (((out_fm[ch]>>1) * cch[ch]->pan_volume_r / 65535) & OPN->pan[chpan]);
			lt  = PANLAW_L(0, 0);
			rt  = PANLAW_R(0, 1);
			lt += PANLAW_L(1, 2);
			rt += PANLAW_R(1, 3);
			lt += PANLAW_L(2, 4);
			rt += PANLAW_R(2, 5);
			lt += PANLAW_L(3, 6);
			rt += PANLAW_R(3, 7);
			lt += PANLAW_L(4, 8);
			rt += PANLAW_R(4, 9);
			lt += PANLAW_L(5, 10);
			rt += PANLAW_R(5, 11);
#undef PANLAW_L
#undef PANLAW_R

			lt >>= FINAL_SH;
			rt >>= FINAL_SH;

			Limit( lt, MAXOUT, MINOUT );
			Limit( rt, MAXOUT, MINOUT );
			/* buffering */
			bufL[i] = lt;
			bufR[i] = rt;

			#ifdef SAVE_SAMPLE
				SAVE_ALL_CHANNELS
			#endif

		}

		/* timer A control */
		INTERNAL_TIMER_A( &OPN->ST , cch[2] )
	}
	INTERNAL_TIMER_B(&OPN->ST,length)


	/* check IRQ for DELTA-T EOS */
	FM_STATUS_SET(&OPN->ST, 0);

}
#ifdef MAME_EMU_SAVE_H
void ym2608_postload(void *chip)
{
	if (chip)
	{
		ym2608_state *F2608 = (ym2608_state *)chip;
		int r;

		/* prescaler */
		OPNPrescaler_w(&F2608->OPN,1,2);
		F2608->deltaT.freqbase = F2608->OPN.ST.freqbase;
		/* IRQ mask / mode */
		YM2608IRQMaskWrite(&F2608->OPN, F2608, F2608->REGS[0x29]);
		/* SSG registers */
		for(r=0;r<16;r++)
		{
			(*F2608->OPN.ST.SSG->write)(F2608->OPN.ST.device,0,r);
			(*F2608->OPN.ST.SSG->write)(F2608->OPN.ST.device,1,F2608->REGS[r]);
		}

		/* OPN registers */
		/* DT / MULTI , TL , KS / AR , AMON / DR , SR , SL / RR , SSG-EG */
		for(r=0x30;r<0x9e;r++)
			if((r&3) != 3)
			{
				OPNWriteReg(&F2608->OPN,r,F2608->REGS[r]);
				OPNWriteReg(&F2608->OPN,r|0x100,F2608->REGS[r|0x100]);
			}
		/* FB / CONNECT , L / R / AMS / PMS */
		for(r=0xb0;r<0xb6;r++)
			if((r&3) != 3)
			{
				OPNWriteReg(&F2608->OPN,r,F2608->REGS[r]);
				OPNWriteReg(&F2608->OPN,r|0x100,F2608->REGS[r|0x100]);
			}
		/* FM channels */
		/*FM_channel_postload(F2608->CH,6);*/
		/* rhythm(ADPCMA) */
		F2608->FM_ADPCMAWrite(1,F2608->REGS[0x111]);
		for( r=0x08 ; r<0x0c ; r++)
			F2608->FM_ADPCMAWrite(r,F2608->REGS[r+0x110]);
		/* Delta-T ADPCM unit */
		F2608->deltaT.postload( &F2608->REGS[0x100] );
	}
}

static void YM2608_save_state(ym2608_state *F2608, device_t *device)
{
	device->save_item(NAME(F2608->REGS));
	FMsave_state_st(device,&F2608->OPN.ST);
	FMsave_state_channel(device,F2608->CH,6);
	/* 3slots */
	device->save_item(NAME(F2608->OPN.SL3.fc));
	device->save_item(NAME(F2608->OPN.SL3.fn_h));
	device->save_item(NAME(F2608->OPN.SL3.kcode));
	/* address register1 */
	device->save_item(NAME(F2608->addr_A1));
	/* rhythm(ADPCMA) */
	FMsave_state_adpcma(device,F2608->adpcm);
	/* Delta-T ADPCM unit */
	F2608->deltaT.savestate(device);
}
#endif /* MAME_EMU_SAVE_H */

static void YM2608_deltat_status_set(void *chip, uint8_t changebits)
{
	ym2608_state *F2608 = (ym2608_state *)chip;
	FM_STATUS_SET(&(F2608->OPN.ST), changebits);
}
static void YM2608_deltat_status_reset(void *chip, uint8_t changebits)
{
	ym2608_state *F2608 = (ym2608_state *)chip;
	FM_STATUS_RESET(&(F2608->OPN.ST), changebits);
}
/* YM2608(OPNA) */
void * ym2608_init(device_t *device, int clock, int rate,
	FM_READBYTE InternalReadByte,
	FM_READBYTE ExternalReadByte, FM_WRITEBYTE ExternalWriteByte,
	FM_TIMERHANDLER timer_handler,FM_IRQHANDLER IRQHandler, const ssg_callbacks *ssg)
{
	ym2608_state *F2608;

	/* allocate extend state space */
	F2608 = new ym2608_state;
	memset(F2608, 0, sizeof(*F2608));
	/* allocate total level table (128kb space) */
	if( !init_tables() )
	{
		delete F2608;
		return NULLPTR;
	}

	F2608->device = device;
	F2608->OPN.type = TYPE_YM2608;
	F2608->OPN.P_CH = F2608->CH;
	F2608->OPN.ST.device = device;
	F2608->OPN.ST.clock = clock;
	F2608->OPN.ST.rate = rate;

	/* External handlers */
	F2608->OPN.ST.timer_handler = timer_handler;
	F2608->OPN.ST.IRQ_Handler   = IRQHandler;
	F2608->OPN.ST.SSG           = ssg;

	/* DELTA-T */
	F2608->deltaT.read_byte = ExternalReadByte;
	F2608->deltaT.write_byte = ExternalWriteByte;

	/*F2608->deltaT.write_time = 20.0 / clock;*/    /* a single byte write takes 20 cycles of main clock */
	/*F2608->deltaT.read_time  = 18.0 / clock;*/    /* a single byte read takes 18 cycles of main clock */

	F2608->deltaT.status_set_handler = YM2608_deltat_status_set;
	F2608->deltaT.status_reset_handler = YM2608_deltat_status_reset;
	F2608->deltaT.status_change_which_chip = F2608;
	F2608->deltaT.status_change_EOS_bit = 0x04; /* status flag: set bit2 on End Of Sample */
	F2608->deltaT.status_change_BRDY_bit = 0x08;    /* status flag: set bit3 on BRDY */
	F2608->deltaT.status_change_ZERO_bit = 0x10;    /* status flag: set bit4 if silence continues for more than 290 milliseconds while recording the ADPCM */

	/* ADPCM Rhythm */
	F2608->read_byte = InternalReadByte;

	Init_ADPCMATable();

	for (unsigned i = 0; i < 6; i++)
	{
		F2608->CH[i].pan_volume_l = 46340;
		F2608->CH[i].pan_volume_r = 46340;
	}

#ifdef MAME_EMU_SAVE_H
	YM2608_save_state(F2608, device);
#endif
	return F2608;
}

void ym2608_clock_changed(void *chip, int clock, int rate)
{
	ym2608_state *F2608 = (ym2608_state *)chip;

	F2608->OPN.ST.clock = clock;
	F2608->OPN.ST.rate = rate;
}

/* shut down emulator */
void ym2608_shutdown(void *chip)
{
	ym2608_state *F2608 = (ym2608_state *)chip;

	FMCloseTable();
	delete F2608;
}

/* reset one of chips */
void ym2608_reset_chip(void *chip)
{
	int i;
	ym2608_state *F2608 = (ym2608_state *)chip;
	FM_OPN *OPN   = &F2608->OPN;
	YM_DELTAT *DELTAT = &F2608->deltaT;

	/* Reset Prescaler */
	OPNPrescaler_w(OPN , 0 , 2);
	F2608->deltaT.freqbase = OPN->ST.freqbase;
	/* reset SSG section */
	(*OPN->ST.SSG->reset)(OPN->ST.device);

	/* status clear */
	FM_BUSY_CLEAR(&OPN->ST);

	/* register 0x29 - default value after reset is:
	    enable only 3 FM channels and enable all the status flags */
	YM2608IRQMaskWrite(OPN, F2608, 0x1f );  /* default value for D4-D0 is 1 */

	/* register 0x10, A1=1 - default value is 1 for D4, D3, D2, 0 for the rest */
	YM2608IRQFlagWrite(OPN, F2608, 0x1c );  /* default: enable timer A and B, disable EOS, BRDY and ZERO */

	OPNWriteMode(OPN,0x27,0x30);    /* mode 0 , timer reset */

	OPN->eg_timer = 0;
	OPN->eg_cnt   = 0;

	FM_STATUS_RESET(&OPN->ST, 0xff);

	reset_channels( &OPN->ST , F2608->CH , 6 );
	/* reset OPerator paramater */
	for(i = 0xb6 ; i >= 0xb4 ; i-- )
	{
		OPNWriteReg(OPN,i      ,0xc0);
		OPNWriteReg(OPN,i|0x100,0xc0);
	}
	for(i = 0xb2 ; i >= 0x30 ; i-- )
	{
		OPNWriteReg(OPN,i      ,0);
		OPNWriteReg(OPN,i|0x100,0);
	}
	for(i = 0x26 ; i >= 0x20 ; i-- ) OPNWriteReg(OPN,i,0);

	/* ADPCM - percussion sounds */
	for( i = 0; i < 6; i++ )
	{
		if (i<=3)   /* channels 0,1,2,3 */
			F2608->adpcm[i].step      = (uint32_t)((float)(1<<ADPCM_SHIFT)*((float)F2608->OPN.ST.freqbase)/3.0f);
		else        /* channels 4 and 5 work with slower clock */
			F2608->adpcm[i].step      = (uint32_t)((float)(1<<ADPCM_SHIFT)*((float)F2608->OPN.ST.freqbase)/6.0f);

		F2608->adpcm[i].start     = YM2608_ADPCM_ROM_addr[i*2];
		F2608->adpcm[i].end       = YM2608_ADPCM_ROM_addr[i*2+1];

		F2608->adpcm[i].now_addr  = 0;
		F2608->adpcm[i].now_step  = 0;
		/* F2608->adpcm[i].delta     = 21866; */
		F2608->adpcm[i].vol_mul   = 0;
		F2608->adpcm[i].pan       = &OPN->out_adpcm[OUTD_CENTER]; /* default center */
		F2608->adpcm[i].flagMask  = 0;
		F2608->adpcm[i].flag      = 0;
		F2608->adpcm[i].adpcm_acc = 0;
		F2608->adpcm[i].adpcm_step= 0;
		F2608->adpcm[i].adpcm_out = 0;
	}
	F2608->adpcmTL = 0x3f;

	F2608->adpcm_arrivedEndAddress = 0; /* not used */

	/* DELTA-T unit */
	DELTAT->freqbase = OPN->ST.freqbase;
	DELTAT->output_pointer = OPN->out_delta;
	DELTAT->portshift = 5;      /* always 5bits shift */ /* ASG */
	DELTAT->output_range = 1<<23;
	DELTAT->ADPCM_Reset(OUTD_CENTER,YM_DELTAT::EMULATION_MODE_NORMAL,F2608->device);
}

/* YM2608 write */
/* n = number  */
/* a = address */
/* v = value   */
int ym2608_write(void *chip, int a,uint8_t v)
{
	ym2608_state *F2608 = (ym2608_state *)chip;
	FM_OPN *OPN   = &F2608->OPN;
	int addr;

	v &= 0xff;  /*adjust to 8 bit bus */


	switch(a&3)
	{
	case 0: /* address port 0 */
		OPN->ST.address = v;
		F2608->addr_A1 = 0;

		/* Write register to SSG emulator */
		if( v < 16 ) (*OPN->ST.SSG->write)(OPN->ST.device,0,v);
		/* prescaler selecter : 2d,2e,2f  */
		if( v >= 0x2d && v <= 0x2f )
		{
			OPNPrescaler_w(OPN , v , 2);
			F2608->deltaT.freqbase = OPN->ST.freqbase;
		}
		break;

	case 1: /* data port 0    */
		if (F2608->addr_A1 != 0)
			break;  /* verified on real YM2608 */

		addr = OPN->ST.address;
		F2608->REGS[addr] = v;
		switch(addr & 0xf0)
		{
		case 0x00:  /* SSG section */
			/* Write data to SSG emulator */
			(*OPN->ST.SSG->write)(OPN->ST.device,a,v);
			break;
		case 0x10:  /* 0x10-0x1f : Rhythm section */
			ym2608_device::update_request(OPN->ST.device);
			F2608->FM_ADPCMAWrite(addr-0x10,v);
			break;
		case 0x20:  /* Mode Register */
			switch(addr)
			{
			case 0x29:  /* SCH,xx,xxx,EN_ZERO,EN_BRDY,EN_EOS,EN_TB,EN_TA */
				YM2608IRQMaskWrite(OPN, F2608, v);
				break;
			default:
				ym2608_device::update_request(OPN->ST.device);
				OPNWriteMode(OPN,addr,v);
			}
			break;
		default:    /* OPN section */
			ym2608_device::update_request(OPN->ST.device);
			OPNWriteReg(OPN,addr,v);
		}
		break;

	case 2: /* address port 1 */
		OPN->ST.address = v;
		F2608->addr_A1 = 1;
		break;

	case 3: /* data port 1    */
		if (F2608->addr_A1 != 1)
			break;  /* verified on real YM2608 */

		addr = OPN->ST.address;
		F2608->REGS[addr | 0x100] = v;
		ym2608_device::update_request(OPN->ST.device);
		switch( addr & 0xf0 )
		{
		case 0x00:  /* DELTAT PORT */
			switch( addr )
			{
			case 0x0e:  /* DAC data */
				F2608->device->logerror("YM2608: write to DAC data (unimplemented) value=%02x\n",v);
				break;
			default:
				/* 0x00-0x0d */
				F2608->deltaT.ADPCM_Write(addr,v);
			}
			break;
		case 0x10:  /* IRQ Flag control */
			if( addr == 0x10 )
			{
				YM2608IRQFlagWrite(OPN, F2608, v);
			}
			break;
		default:
			OPNWriteReg(OPN,addr | 0x100,v);
		}
	}
	return OPN->ST.irq;
}

// libOPNMIDI: soft panning
void ym2608_write_pan(void *chip, int c, unsigned char v)
{
	ym2608_state *F2608 = (ym2608_state *)chip;
	assert((c >= 0) && (c < 6));
	F2608->CH[c].pan_volume_l = panlawtable[v & 0x7F];
	F2608->CH[c].pan_volume_r = panlawtable[0x7F - (v & 0x7F)];
}

uint8_t ym2608_read(void *chip,int a)
{
	ym2608_state *F2608 = (ym2608_state *)chip;
	int addr = F2608->OPN.ST.address;
	uint8_t ret = 0;

	switch( a&3 )
	{
	case 0: /* status 0 : YM2203 compatible */
		/* BUSY:x:x:x:x:x:FLAGB:FLAGA */
		ret = FM_STATUS_FLAG(&F2608->OPN.ST) & 0x83;
		break;

	case 1: /* status 0, ID  */
		if( addr < 16 ) ret = (*F2608->OPN.ST.SSG->read)(F2608->OPN.ST.device);
		else if(addr == 0xff) ret = 0x01; /* ID code */
		break;

	case 2: /* status 1 : status 0 + ADPCM status */
		/* BUSY : x : PCMBUSY : ZERO : BRDY : EOS : FLAGB : FLAGA */
		ret = (FM_STATUS_FLAG(&F2608->OPN.ST) & (F2608->flagmask|0x80)) | ((F2608->deltaT.PCM_BSY & 1)<<5) ;
		break;

	case 3:
		if(addr == 0x08)
		{
			ret = F2608->deltaT.ADPCM_Read();
		}
		else
		{
			if(addr == 0x0f)
			{
				F2608->device->logerror("YM2608 A/D conversion is accessed but not implemented !\n");
				ret = 0x80; /* 2's complement PCM data - result from A/D conversion */
			}
		}
		break;
	}
	return ret;
}

int ym2608_timer_over(void *chip,int c)
{
	ym2608_state *F2608 = (ym2608_state *)chip;

	switch(c)
	{
#if 0
	case 2:
		{   /* BUFRDY flag */
			F2608->deltaT.BRDY_callback();
		}
		break;
#endif
	case 1:
		{   /* Timer B */
			TimerBOver( &(F2608->OPN.ST) );
		}
		break;
	case 0:
		{   /* Timer A */
			ym2608_device::update_request(F2608->OPN.ST.device);
			/* timer update */
			TimerAOver( &(F2608->OPN.ST) );
			/* CSM mode key,TL controll */
			if( F2608->OPN.ST.mode & 0x80 )
			{   /* CSM mode total level latch and auto key on */
				CSMKeyControll( F2608->OPN.type, &(F2608->CH[2]) );
			}
		}
		break;
	default:
		break;
	}

	return F2608->OPN.ST.irq;
}

#endif /* BUILD_YM2608 */



#if (BUILD_YM2610||BUILD_YM2610B)
/* YM2610(OPNB) */

/* Generate samples for one of the YM2610s */
void ym2610_update_one(void *chip, FMSAMPLE **buffer, int length)
{
	ym2610_state *F2610 = (ym2610_state *)chip;
	FM_OPN *OPN   = &F2610->OPN;
	YM_DELTAT *DELTAT = &F2610->deltaT;
	int i,j;
	FMSAMPLE  *bufL,*bufR;
	FM_CH   *cch[4];
	int32_t *out_fm = OPN->out_fm;

	/* buffer setup */
	bufL = buffer[0];
	bufR = buffer[1];

	cch[0] = &F2610->CH[1];
	cch[1] = &F2610->CH[2];
	cch[2] = &F2610->CH[4];
	cch[3] = &F2610->CH[5];

#ifdef YM2610B_WARNING
#define FM_KEY_IS(SLOT) ((SLOT)->key)
#define FM_MSG_YM2610B "YM2610-%p.CH%d is playing,Check whether the type of the chip is YM2610B\n"
	/* Check YM2610B warning message */
	if( FM_KEY_IS(&F2610->CH[0].SLOT[3]) )
		LOG(F2610->device,LOG_WAR,(FM_MSG_YM2610B,F2610->OPN.ST.device,0));
	if( FM_KEY_IS(&F2610->CH[3].SLOT[3]) )
		LOG(F2610->device,LOG_WAR,(FM_MSG_YM2610B,F2610->OPN.ST.device,3));
#endif

	/* refresh PG and EG */
	refresh_fc_eg_chan( OPN, cch[0] );
	if( (OPN->ST.mode & 0xc0) )
	{
		/* 3SLOT MODE */
		if( cch[1]->SLOT[SLOT1].Incr==-1)
		{
			refresh_fc_eg_slot(OPN, &cch[1]->SLOT[SLOT1] , OPN->SL3.fc[1] , OPN->SL3.kcode[1] );
			refresh_fc_eg_slot(OPN, &cch[1]->SLOT[SLOT2] , OPN->SL3.fc[2] , OPN->SL3.kcode[2] );
			refresh_fc_eg_slot(OPN, &cch[1]->SLOT[SLOT3] , OPN->SL3.fc[0] , OPN->SL3.kcode[0] );
			refresh_fc_eg_slot(OPN, &cch[1]->SLOT[SLOT4] , cch[1]->fc , cch[1]->kcode );
		}
	}
	else
		refresh_fc_eg_chan( OPN, cch[1] );
	refresh_fc_eg_chan( OPN, cch[2] );
	refresh_fc_eg_chan( OPN, cch[3] );

	/* buffering */
	for(i=0; i < length ; i++)
	{
		advance_lfo(OPN);

		/* clear output acc. */
		OPN->out_adpcm[OUTD_LEFT] = OPN->out_adpcm[OUTD_RIGHT] = OPN->out_adpcm[OUTD_CENTER] = 0;
		OPN->out_delta[OUTD_LEFT] = OPN->out_delta[OUTD_RIGHT] = OPN->out_delta[OUTD_CENTER] = 0;
		/* clear outputs */
		out_fm[1] = 0;
		out_fm[2] = 0;
		out_fm[4] = 0;
		out_fm[5] = 0;

		/* advance envelope generator */
		OPN->eg_timer += OPN->eg_timer_add;
		while (OPN->eg_timer >= OPN->eg_timer_overflow)
		{
			OPN->eg_timer -= OPN->eg_timer_overflow;
			OPN->eg_cnt++;

			advance_eg_channel(OPN, &cch[0]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[1]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[2]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[3]->SLOT[SLOT1]);
		}

		/* calculate FM */
		chan_calc(OPN, cch[0], 1 ); /*remapped to 1*/
		chan_calc(OPN, cch[1], 2 ); /*remapped to 2*/
		chan_calc(OPN, cch[2], 4 ); /*remapped to 4*/
		chan_calc(OPN, cch[3], 5 ); /*remapped to 5*/

		/* deltaT ADPCM */
		if( DELTAT->portstate&0x80 )
			DELTAT->ADPCM_CALC();

		/* ADPCMA */
		for( j = 0; j < 6; j++ )
		{
			if( F2610->adpcm[j].flag )
				F2610->ADPCMA_calc_chan(&F2610->adpcm[j]);
		}

		/* buffering */
		{
			int lt,rt;

			lt =  OPN->out_adpcm[OUTD_LEFT]  + OPN->out_adpcm[OUTD_CENTER];
			rt =  OPN->out_adpcm[OUTD_RIGHT] + OPN->out_adpcm[OUTD_CENTER];
			lt += (OPN->out_delta[OUTD_LEFT]  + OPN->out_delta[OUTD_CENTER])>>9;
			rt += (OPN->out_delta[OUTD_RIGHT] + OPN->out_delta[OUTD_CENTER])>>9;


			lt += ((out_fm[1]>>1) & OPN->pan[2]);   /* the shift right was verified on real chip */
			rt += ((out_fm[1]>>1) & OPN->pan[3]);
			lt += ((out_fm[2]>>1) & OPN->pan[4]);
			rt += ((out_fm[2]>>1) & OPN->pan[5]);

			lt += ((out_fm[4]>>1) & OPN->pan[8]);
			rt += ((out_fm[4]>>1) & OPN->pan[9]);
			lt += ((out_fm[5]>>1) & OPN->pan[10]);
			rt += ((out_fm[5]>>1) & OPN->pan[11]);


			lt >>= FINAL_SH;
			rt >>= FINAL_SH;

			Limit( lt, MAXOUT, MINOUT );
			Limit( rt, MAXOUT, MINOUT );

			#ifdef SAVE_SAMPLE
				SAVE_ALL_CHANNELS
			#endif

			/* buffering */
			bufL[i] = lt;
			bufR[i] = rt;
		}

		/* timer A control */
		INTERNAL_TIMER_A( &OPN->ST , cch[1] )
	}
	INTERNAL_TIMER_B(&OPN->ST,length)

}

#if BUILD_YM2610B
/* Generate samples for one of the YM2610Bs */
void ym2610b_update_one(void *chip, FMSAMPLE **buffer, int length)
{
	ym2610_state *F2610 = (ym2610_state *)chip;
	FM_OPN *OPN   = &F2610->OPN;
	YM_DELTAT *DELTAT = &F2610->deltaT;
	int i,j;
	FMSAMPLE  *bufL,*bufR;
	FM_CH   *cch[6];
	int32_t *out_fm = OPN->out_fm;

	/* buffer setup */
	bufL = buffer[0];
	bufR = buffer[1];

	cch[0] = &F2610->CH[0];
	cch[1] = &F2610->CH[1];
	cch[2] = &F2610->CH[2];
	cch[3] = &F2610->CH[3];
	cch[4] = &F2610->CH[4];
	cch[5] = &F2610->CH[5];

	/* refresh PG and EG */
	refresh_fc_eg_chan( OPN, cch[0] );
	refresh_fc_eg_chan( OPN, cch[1] );
	if( (OPN->ST.mode & 0xc0) )
	{
		/* 3SLOT MODE */
		if( cch[2]->SLOT[SLOT1].Incr==-1)
		{
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT1] , OPN->SL3.fc[1] , OPN->SL3.kcode[1] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT2] , OPN->SL3.fc[2] , OPN->SL3.kcode[2] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT3] , OPN->SL3.fc[0] , OPN->SL3.kcode[0] );
			refresh_fc_eg_slot(OPN, &cch[2]->SLOT[SLOT4] , cch[2]->fc , cch[2]->kcode );
		}
	}
	else
		refresh_fc_eg_chan( OPN, cch[2] );
	refresh_fc_eg_chan( OPN, cch[3] );
	refresh_fc_eg_chan( OPN, cch[4] );
	refresh_fc_eg_chan( OPN, cch[5] );

	/* buffering */
	for(i=0; i < length ; i++)
	{
		advance_lfo(OPN);

		/* clear output acc. */
		OPN->out_adpcm[OUTD_LEFT] = OPN->out_adpcm[OUTD_RIGHT] = OPN->out_adpcm[OUTD_CENTER] = 0;
		OPN->out_delta[OUTD_LEFT] = OPN->out_delta[OUTD_RIGHT] = OPN->out_delta[OUTD_CENTER] = 0;
		/* clear outputs */
		out_fm[0] = 0;
		out_fm[1] = 0;
		out_fm[2] = 0;
		out_fm[3] = 0;
		out_fm[4] = 0;
		out_fm[5] = 0;

		/* advance envelope generator */
		OPN->eg_timer += OPN->eg_timer_add;
		while (OPN->eg_timer >= OPN->eg_timer_overflow)
		{
			OPN->eg_timer -= OPN->eg_timer_overflow;
			OPN->eg_cnt++;

			advance_eg_channel(OPN, &cch[0]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[1]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[2]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[3]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[4]->SLOT[SLOT1]);
			advance_eg_channel(OPN, &cch[5]->SLOT[SLOT1]);
		}

		/* calculate FM */
		chan_calc(OPN, cch[0], 0 );
		chan_calc(OPN, cch[1], 1 );
		chan_calc(OPN, cch[2], 2 );
		chan_calc(OPN, cch[3], 3 );
		chan_calc(OPN, cch[4], 4 );
		chan_calc(OPN, cch[5], 5 );

		/* deltaT ADPCM */
		if( DELTAT->portstate&0x80 )
			DELTAT->ADPCM_CALC();

		/* ADPCMA */
		for( j = 0; j < 6; j++ )
		{
			if( F2610->adpcm[j].flag )
				F2610->ADPCMA_calc_chan(&F2610->adpcm[j]);
		}

		/* buffering */
		{
			int lt,rt;

			lt =  OPN->out_adpcm[OUTD_LEFT]  + OPN->out_adpcm[OUTD_CENTER];
			rt =  OPN->out_adpcm[OUTD_RIGHT] + OPN->out_adpcm[OUTD_CENTER];
			lt += (OPN->out_delta[OUTD_LEFT]  + OPN->out_delta[OUTD_CENTER])>>9;
			rt += (OPN->out_delta[OUTD_RIGHT] + OPN->out_delta[OUTD_CENTER])>>9;

			lt += ((out_fm[0]>>1) & OPN->pan[0]);   /* the shift right is verified on YM2610 */
			rt += ((out_fm[0]>>1) & OPN->pan[1]);
			lt += ((out_fm[1]>>1) & OPN->pan[2]);
			rt += ((out_fm[1]>>1) & OPN->pan[3]);
			lt += ((out_fm[2]>>1) & OPN->pan[4]);
			rt += ((out_fm[2]>>1) & OPN->pan[5]);
			lt += ((out_fm[3]>>1) & OPN->pan[6]);
			rt += ((out_fm[3]>>1) & OPN->pan[7]);
			lt += ((out_fm[4]>>1) & OPN->pan[8]);
			rt += ((out_fm[4]>>1) & OPN->pan[9]);
			lt += ((out_fm[5]>>1) & OPN->pan[10]);
			rt += ((out_fm[5]>>1) & OPN->pan[11]);


			lt >>= FINAL_SH;
			rt >>= FINAL_SH;

			Limit( lt, MAXOUT, MINOUT );
			Limit( rt, MAXOUT, MINOUT );

			#ifdef SAVE_SAMPLE
				SAVE_ALL_CHANNELS
			#endif

			/* buffering */
			bufL[i] = lt;
			bufR[i] = rt;
		}

		/* timer A control */
		INTERNAL_TIMER_A( &OPN->ST , cch[2] )
	}
	INTERNAL_TIMER_B(&OPN->ST,length)

}
#endif /* BUILD_YM2610B */


#ifdef MAME_EMU_SAVE_H
void ym2610_postload(void *chip)
{
	if (chip)
	{
		ym2610_state *F2610 = (ym2610_state *)chip;
		int r;

		/* SSG registers */
		for(r=0;r<16;r++)
		{
			(*F2610->OPN.ST.SSG->write)(F2610->OPN.ST.device,0,r);
			(*F2610->OPN.ST.SSG->write)(F2610->OPN.ST.device,1,F2610->REGS[r]);
		}

		/* OPN registers */
		/* DT / MULTI , TL , KS / AR , AMON / DR , SR , SL / RR , SSG-EG */
		for(r=0x30;r<0x9e;r++)
			if((r&3) != 3)
			{
				OPNWriteReg(&F2610->OPN,r,F2610->REGS[r]);
				OPNWriteReg(&F2610->OPN,r|0x100,F2610->REGS[r|0x100]);
			}
		/* FB / CONNECT , L / R / AMS / PMS */
		for(r=0xb0;r<0xb6;r++)
			if((r&3) != 3)
			{
				OPNWriteReg(&F2610->OPN,r,F2610->REGS[r]);
				OPNWriteReg(&F2610->OPN,r|0x100,F2610->REGS[r|0x100]);
			}
		/* FM channels */
		/*FM_channel_postload(F2610->CH,6);*/

		/* rhythm(ADPCMA) */
		F2610->FM_ADPCMAWrite(1,F2610->REGS[0x101]);
		for( r=0 ; r<6 ; r++)
		{
			F2610->FM_ADPCMAWrite(r+0x08,F2610->REGS[r+0x108]);
			F2610->FM_ADPCMAWrite(r+0x10,F2610->REGS[r+0x110]);
			F2610->FM_ADPCMAWrite(r+0x18,F2610->REGS[r+0x118]);
			F2610->FM_ADPCMAWrite(r+0x20,F2610->REGS[r+0x120]);
			F2610->FM_ADPCMAWrite(r+0x28,F2610->REGS[r+0x128]);
		}
		/* Delta-T ADPCM unit */
		F2610->deltaT.postload( &F2610->REGS[0x010] );
	}
}

static void YM2610_save_state(ym2610_state *F2610, device_t *device)
{
	device->save_item(NAME(F2610->REGS));
	FMsave_state_st(device,&F2610->OPN.ST);
	FMsave_state_channel(device,F2610->CH,6);
	/* 3slots */
	device->save_item(NAME(F2610->OPN.SL3.fc));
	device->save_item(NAME(F2610->OPN.SL3.fn_h));
	device->save_item(NAME(F2610->OPN.SL3.kcode));
	/* address register1 */
	device->save_item(NAME(F2610->addr_A1));

	device->save_item(NAME(F2610->adpcm_arrivedEndAddress));
	/* rhythm(ADPCMA) */
	FMsave_state_adpcma(device,F2610->adpcm);
	/* Delta-T ADPCM unit */
	F2610->deltaT.savestate(device);
}
#endif /* MAME_EMU_SAVE_H */

static void YM2610_deltat_status_set(void *chip, uint8_t changebits)
{
	ym2610_state *F2610 = (ym2610_state *)chip;
	F2610->adpcm_arrivedEndAddress |= changebits;
}
static void YM2610_deltat_status_reset(void *chip, uint8_t changebits)
{
	ym2610_state *F2610 = (ym2610_state *)chip;
	F2610->adpcm_arrivedEndAddress &= (~changebits);
}

void *ym2610_init(device_t *device, int clock, int rate,
	FM_READBYTE adpcm_a_read_byte, FM_READBYTE adpcm_b_read_byte,
	FM_TIMERHANDLER timer_handler,FM_IRQHANDLER IRQHandler, const ssg_callbacks *ssg)
{
	ym2610_state *F2610;

	/* allocate extend state space */
	F2610 = new ym2610_state;
	memset(F2610, 0, sizeof(*F2610));
	/* allocate total level table (128kb space) */
	if( !init_tables() )
	{
		delete F2610;
		return nullptr;
	}

	F2610->device = device;
	/* FM */
	F2610->OPN.type = TYPE_YM2610;
	F2610->OPN.P_CH = F2610->CH;
	F2610->OPN.ST.device = device;
	F2610->OPN.ST.clock = clock;
	F2610->OPN.ST.rate = rate;
	/* Extend handler */
	F2610->OPN.ST.timer_handler = timer_handler;
	F2610->OPN.ST.IRQ_Handler   = IRQHandler;
	F2610->OPN.ST.SSG           = ssg;
	/* ADPCM */
	F2610->read_byte = adpcm_a_read_byte;
	/* DELTA-T */
	F2610->deltaT.read_byte = adpcm_b_read_byte;
	F2610->deltaT.write_byte = nullptr;

	F2610->deltaT.status_set_handler = YM2610_deltat_status_set;
	F2610->deltaT.status_reset_handler = YM2610_deltat_status_reset;
	F2610->deltaT.status_change_which_chip = F2610;
	F2610->deltaT.status_change_EOS_bit = 0x80; /* status flag: set bit7 on End Of Sample */

	Init_ADPCMATable();

	for (unsigned i = 0; i < 6; i++)
	{
		F2610->CH[i].pan_volume_l = 46340;
		F2610->CH[i].pan_volume_r = 46340;
	}

#ifdef MAME_EMU_SAVE_H
	YM2610_save_state(F2610, device);
#endif
	return F2610;
}

void ym2610_clock_changed(void *chip, int clock, int rate)
{
	ym2610_state *F2610 = (ym2610_state *)chip;

	F2610->OPN.ST.clock = clock;
	F2610->OPN.ST.rate = rate;
}

/* shut down emulator */
void ym2610_shutdown(void *chip)
{
	ym2610_state *F2610 = (ym2610_state *)chip;

	FMCloseTable();
	delete F2610;
}

/* reset one of chip */
void ym2610_reset_chip(void *chip)
{
	int i;
	ym2610_state *F2610 = (ym2610_state *)chip;
	FM_OPN *OPN   = &F2610->OPN;
	YM_DELTAT *DELTAT = &F2610->deltaT;

	device_t* dev = F2610->OPN.ST.device;
	std::string name(dev->tag());

	/* Reset Prescaler */
	OPNSetPres( OPN, 6*24, 6*24, 4*2); /* OPN 1/6 , SSG 1/4 */
	/* reset SSG section */
	(*OPN->ST.SSG->reset)(OPN->ST.device);
	/* status clear */
	FM_IRQMASK_SET(&OPN->ST,0x03);
	FM_BUSY_CLEAR(&OPN->ST);
	OPNWriteMode(OPN,0x27,0x30); /* mode 0 , timer reset */

	OPN->eg_timer = 0;
	OPN->eg_cnt   = 0;

	FM_STATUS_RESET(&OPN->ST, 0xff);

	reset_channels( &OPN->ST , F2610->CH , 6 );
	/* reset OPerator paramater */
	for(i = 0xb6 ; i >= 0xb4 ; i-- )
	{
		OPNWriteReg(OPN,i      ,0xc0);
		OPNWriteReg(OPN,i|0x100,0xc0);
	}
	for(i = 0xb2 ; i >= 0x30 ; i-- )
	{
		OPNWriteReg(OPN,i      ,0);
		OPNWriteReg(OPN,i|0x100,0);
	}
	for(i = 0x26 ; i >= 0x20 ; i-- ) OPNWriteReg(OPN,i,0);
	/**** ADPCM work initial ****/
	for( i = 0; i < 6 ; i++ )
	{
		F2610->adpcm[i].step      = (uint32_t)((float)(1<<ADPCM_SHIFT)*((float)F2610->OPN.ST.freqbase)/3.0f);
		F2610->adpcm[i].now_addr  = 0;
		F2610->adpcm[i].now_step  = 0;
		F2610->adpcm[i].start     = 0;
		F2610->adpcm[i].end       = 0;
		/* F2610->adpcm[i].delta     = 21866; */
		F2610->adpcm[i].vol_mul   = 0;
		F2610->adpcm[i].pan       = &OPN->out_adpcm[OUTD_CENTER]; /* default center */
		F2610->adpcm[i].flagMask  = 1<<i;
		F2610->adpcm[i].flag      = 0;
		F2610->adpcm[i].adpcm_acc = 0;
		F2610->adpcm[i].adpcm_step= 0;
		F2610->adpcm[i].adpcm_out = 0;
	}
	F2610->adpcmTL = 0x3f;

	F2610->adpcm_arrivedEndAddress = 0;

	/* DELTA-T unit */
	DELTAT->freqbase = OPN->ST.freqbase;
	DELTAT->output_pointer = OPN->out_delta;
	DELTAT->portshift = 8;      /* allways 8bits shift */
	DELTAT->output_range = 1<<23;
	DELTAT->ADPCM_Reset(OUTD_CENTER,YM_DELTAT::EMULATION_MODE_YM2610,F2610->device);
}

/* YM2610 write */
/* n = number  */
/* a = address */
/* v = value   */
int ym2610_write(void *chip, int a, uint8_t v)
{
	ym2610_state *F2610 = (ym2610_state *)chip;
	FM_OPN *OPN   = &F2610->OPN;
	int addr;
	int ch;

	v &= 0xff;  /* adjust to 8 bit bus */

	switch( a&3 )
	{
	case 0: /* address port 0 */
		OPN->ST.address = v;
		F2610->addr_A1 = 0;

		/* Write register to SSG emulator */
		if( v < 16 ) (*OPN->ST.SSG->write)(OPN->ST.device,0,v);
		break;

	case 1: /* data port 0    */
		if (F2610->addr_A1 != 0)
			break;  /* verified on real YM2608 */

		addr = OPN->ST.address;
		F2610->REGS[addr] = v;
		switch(addr & 0xf0)
		{
		case 0x00:  /* SSG section */
			/* Write data to SSG emulator */
			(*OPN->ST.SSG->write)(OPN->ST.device,a,v);
			break;
		case 0x10: /* DeltaT ADPCM */
			ym2610_device::update_request(OPN->ST.device);

			switch(addr)
			{
			case 0x10:  /* control 1 */
			case 0x11:  /* control 2 */
			case 0x12:  /* start address L */
			case 0x13:  /* start address H */
			case 0x14:  /* stop address L */
			case 0x15:  /* stop address H */

			case 0x19:  /* delta-n L */
			case 0x1a:  /* delta-n H */
			case 0x1b:  /* volume */
				{
					F2610->deltaT.ADPCM_Write(addr-0x10,v);
				}
				break;

			case 0x1c: /*  FLAG CONTROL : Extend Status Clear/Mask */
				{
					uint8_t statusmask = ~v;
					/* set arrived flag mask */
					for(ch=0;ch<6;ch++)
						F2610->adpcm[ch].flagMask = statusmask&(1<<ch);

					F2610->deltaT.status_change_EOS_bit = statusmask & 0x80;    /* status flag: set bit7 on End Of Sample */

					/* clear arrived flag */
					F2610->adpcm_arrivedEndAddress &= statusmask;
				}
				break;

			default:
				F2610->device->logerror("YM2610: write to unknown deltat register %02x val=%02x\n",addr,v);
				break;
			}

			break;
		case 0x20:  /* Mode Register */
			ym2610_device::update_request(OPN->ST.device);
			OPNWriteMode(OPN,addr,v);
			break;
		default:    /* OPN section */
			ym2610_device::update_request(OPN->ST.device);
			/* write register */
			OPNWriteReg(OPN,addr,v);
		}
		break;

	case 2: /* address port 1 */
		OPN->ST.address = v;
		F2610->addr_A1 = 1;
		break;

	case 3: /* data port 1    */
		if (F2610->addr_A1 != 1)
			break;  /* verified on real YM2608 */

		ym2610_device::update_request(OPN->ST.device);
		addr = OPN->ST.address;
		F2610->REGS[addr | 0x100] = v;
		if( addr < 0x30 )
			/* 100-12f : ADPCM A section */
			F2610->FM_ADPCMAWrite(addr,v);
		else
			OPNWriteReg(OPN,addr | 0x100,v);
	}
	return OPN->ST.irq;
}

uint8_t ym2610_read(void *chip,int a)
{
	ym2610_state *F2610 = (ym2610_state *)chip;
	int addr = F2610->OPN.ST.address;
	uint8_t ret = 0;

	switch( a&3)
	{
	case 0: /* status 0 : YM2203 compatible */
		ret = FM_STATUS_FLAG(&F2610->OPN.ST) & 0x83;
		break;
	case 1: /* data 0 */
		if( addr < 16 ) ret = (*F2610->OPN.ST.SSG->read)(F2610->OPN.ST.device);
		if( addr == 0xff ) ret = 0x01;
		break;
	case 2: /* status 1 : ADPCM status */
		/* ADPCM STATUS (arrived End Address) */
		/* B,--,A5,A4,A3,A2,A1,A0 */
		/* B     = ADPCM-B(DELTA-T) arrived end address */
		/* A0-A5 = ADPCM-A          arrived end address */
		ret = F2610->adpcm_arrivedEndAddress;
		break;
	case 3:
		ret = 0;
		break;
	}
	return ret;
}

int ym2610_timer_over(void *chip,int c)
{
	ym2610_state *F2610 = (ym2610_state *)chip;

	if( c )
	{   /* Timer B */
		TimerBOver( &(F2610->OPN.ST) );
	}
	else
	{   /* Timer A */
		ym2610_device::update_request(F2610->OPN.ST.device);
		/* timer update */
		TimerAOver( &(F2610->OPN.ST) );
		/* CSM mode key,TL controll */
		if( F2610->OPN.ST.mode & 0x80 )
		{   /* CSM mode total level latch and auto key on */
			CSMKeyControll( F2610->OPN.type, &(F2610->CH[2]) );
		}
	}
	return F2610->OPN.ST.irq;
}

#endif /* (BUILD_YM2610||BUILD_YM2610B) */
