/*****************************************************************************
*
*   Yamaha YM2151 driver (version 2.150 final beta)
*
******************************************************************************/

#include <math.h>
#include "emumain.h"

#include "okim6295.c"

#ifndef PI
#define PI 3.14159265358979323846
#endif

#define FREQ_SH			16  /* 16.16 fixed point (frequency calculations) */
#define EG_SH			16  /* 16.16 fixed point (envelope generator timing) */
#define LFO_SH			10  /* 22.10 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) */


#define FINAL_SH	(0)
#define MAXOUT		(+32767)
#define MINOUT		(-32768)


/*  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 s32 tl_tab[TL_TAB_LEN];

#define ENV_QUIET		(TL_TAB_LEN>>3)

/* sin waveform table in 'decibel' scale */
static u32 sin_tab[SIN_LEN];


/* translate from D1L to volume index (16 D1L levels) */
static u32 d1l_tab[16];


#define RATE_STEPS (8)
static const u8 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 u8 ALIGN_DATA eg_rate_select[32+64+32]={	/* Envelope Generator rates (32 + 64 rates + 32 RKS) */
/* 32 dummy (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 u8 ALIGN_DATA 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

/*  DT2 defines offset in cents from base note
*
*   This table defines offset in frequency-deltas table.
*   User's Manual page 22
*
*   Values below were calculated using formula: value =  orig.val / 1.5625
*
*   DT2=0 DT2=1 DT2=2 DT2=3
*   0     600   781   950
*/
static const u32 ALIGN_DATA dt2_tab[4] = { 0, 384, 500, 608 };

/*  DT1 defines offset in Hertz from base note
*   This table is converted while initialization...
*   Detune table shown in YM2151 User's Manual is wrong (verified on the real chip)
*/

static const u8 ALIGN_DATA dt1_tab[4*32] = { /* 4*32 DT1 values */
/* DT1=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,

/* DT1=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,

/* DT1=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,

/* DT1=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
};

static const u16 ALIGN_DATA phaseinc_rom[768]={
1299,1300,1301,1302,1303,1304,1305,1306,1308,1309,1310,1311,1313,1314,1315,1316,
1318,1319,1320,1321,1322,1323,1324,1325,1327,1328,1329,1330,1332,1333,1334,1335,
1337,1338,1339,1340,1341,1342,1343,1344,1346,1347,1348,1349,1351,1352,1353,1354,
1356,1357,1358,1359,1361,1362,1363,1364,1366,1367,1368,1369,1371,1372,1373,1374,
1376,1377,1378,1379,1381,1382,1383,1384,1386,1387,1388,1389,1391,1392,1393,1394,
1396,1397,1398,1399,1401,1402,1403,1404,1406,1407,1408,1409,1411,1412,1413,1414,
1416,1417,1418,1419,1421,1422,1423,1424,1426,1427,1429,1430,1431,1432,1434,1435,
1437,1438,1439,1440,1442,1443,1444,1445,1447,1448,1449,1450,1452,1453,1454,1455,
1458,1459,1460,1461,1463,1464,1465,1466,1468,1469,1471,1472,1473,1474,1476,1477,
1479,1480,1481,1482,1484,1485,1486,1487,1489,1490,1492,1493,1494,1495,1497,1498,
1501,1502,1503,1504,1506,1507,1509,1510,1512,1513,1514,1515,1517,1518,1520,1521,
1523,1524,1525,1526,1528,1529,1531,1532,1534,1535,1536,1537,1539,1540,1542,1543,
1545,1546,1547,1548,1550,1551,1553,1554,1556,1557,1558,1559,1561,1562,1564,1565,
1567,1568,1569,1570,1572,1573,1575,1576,1578,1579,1580,1581,1583,1584,1586,1587,
1590,1591,1592,1593,1595,1596,1598,1599,1601,1602,1604,1605,1607,1608,1609,1610,
1613,1614,1615,1616,1618,1619,1621,1622,1624,1625,1627,1628,1630,1631,1632,1633,
1637,1638,1639,1640,1642,1643,1645,1646,1648,1649,1651,1652,1654,1655,1656,1657,
1660,1661,1663,1664,1666,1667,1669,1670,1672,1673,1675,1676,1678,1679,1681,1682,
1685,1686,1688,1689,1691,1692,1694,1695,1697,1698,1700,1701,1703,1704,1706,1707,
1709,1710,1712,1713,1715,1716,1718,1719,1721,1722,1724,1725,1727,1728,1730,1731,
1734,1735,1737,1738,1740,1741,1743,1744,1746,1748,1749,1751,1752,1754,1755,1757,
1759,1760,1762,1763,1765,1766,1768,1769,1771,1773,1774,1776,1777,1779,1780,1782,
1785,1786,1788,1789,1791,1793,1794,1796,1798,1799,1801,1802,1804,1806,1807,1809,
1811,1812,1814,1815,1817,1819,1820,1822,1824,1825,1827,1828,1830,1832,1833,1835,
1837,1838,1840,1841,1843,1845,1846,1848,1850,1851,1853,1854,1856,1858,1859,1861,
1864,1865,1867,1868,1870,1872,1873,1875,1877,1879,1880,1882,1884,1885,1887,1888,
1891,1892,1894,1895,1897,1899,1900,1902,1904,1906,1907,1909,1911,1912,1914,1915,
1918,1919,1921,1923,1925,1926,1928,1930,1932,1933,1935,1937,1939,1940,1942,1944,
1946,1947,1949,1951,1953,1954,1956,1958,1960,1961,1963,1965,1967,1968,1970,1972,
1975,1976,1978,1980,1982,1983,1985,1987,1989,1990,1992,1994,1996,1997,1999,2001,
2003,2004,2006,2008,2010,2011,2013,2015,2017,2019,2021,2022,2024,2026,2028,2029,
2032,2033,2035,2037,2039,2041,2043,2044,2047,2048,2050,2052,2054,2056,2058,2059,
2062,2063,2065,2067,2069,2071,2073,2074,2077,2078,2080,2082,2084,2086,2088,2089,
2092,2093,2095,2097,2099,2101,2103,2104,2107,2108,2110,2112,2114,2116,2118,2119,
2122,2123,2125,2127,2129,2131,2133,2134,2137,2139,2141,2142,2145,2146,2148,2150,
2153,2154,2156,2158,2160,2162,2164,2165,2168,2170,2172,2173,2176,2177,2179,2181,
2185,2186,2188,2190,2192,2194,2196,2197,2200,2202,2204,2205,2208,2209,2211,2213,
2216,2218,2220,2222,2223,2226,2227,2230,2232,2234,2236,2238,2239,2242,2243,2246,
2249,2251,2253,2255,2256,2259,2260,2263,2265,2267,2269,2271,2272,2275,2276,2279,
2281,2283,2285,2287,2288,2291,2292,2295,2297,2299,2301,2303,2304,2307,2308,2311,
2315,2317,2319,2321,2322,2325,2326,2329,2331,2333,2335,2337,2338,2341,2342,2345,
2348,2350,2352,2354,2355,2358,2359,2362,2364,2366,2368,2370,2371,2374,2375,2378,
2382,2384,2386,2388,2389,2392,2393,2396,2398,2400,2402,2404,2407,2410,2411,2414,
2417,2419,2421,2423,2424,2427,2428,2431,2433,2435,2437,2439,2442,2445,2446,2449,
2452,2454,2456,2458,2459,2462,2463,2466,2468,2470,2472,2474,2477,2480,2481,2484,
2488,2490,2492,2494,2495,2498,2499,2502,2504,2506,2508,2510,2513,2516,2517,2520,
2524,2526,2528,2530,2531,2534,2535,2538,2540,2542,2544,2546,2549,2552,2553,2556,
2561,2563,2565,2567,2568,2571,2572,2575,2577,2579,2581,2583,2586,2589,2590,2593
};


/*
    Noise LFO waveform.

    Here are just 256 samples out of much longer data.

    It does NOT repeat every 256 samples on real chip and I wasnt able to find
    the point where it repeats (even in strings as long as 131072 samples).

    I only put it here because its better than nothing and perhaps
    someone might be able to figure out the real algorithm.


    Note that (due to the way the LFO output is calculated) it is quite
    possible that two values: 0x80 and 0x00 might be wrong in this table.
    To be exact:
        some 0x80 could be 0x81 as well as some 0x00 could be 0x01.
*/

static const u8 ALIGN_DATA lfo_noise_waveform[256] = {
0xFF,0xEE,0xD3,0x80,0x58,0xDA,0x7F,0x94,0x9E,0xE3,0xFA,0x00,0x4D,0xFA,0xFF,0x6A,
0x7A,0xDE,0x49,0xF6,0x00,0x33,0xBB,0x63,0x91,0x60,0x51,0xFF,0x00,0xD8,0x7F,0xDE,
0xDC,0x73,0x21,0x85,0xB2,0x9C,0x5D,0x24,0xCD,0x91,0x9E,0x76,0x7F,0x20,0xFB,0xF3,
0x00,0xA6,0x3E,0x42,0x27,0x69,0xAE,0x33,0x45,0x44,0x11,0x41,0x72,0x73,0xDF,0xA2,

0x32,0xBD,0x7E,0xA8,0x13,0xEB,0xD3,0x15,0xDD,0xFB,0xC9,0x9D,0x61,0x2F,0xBE,0x9D,
0x23,0x65,0x51,0x6A,0x84,0xF9,0xC9,0xD7,0x23,0xBF,0x65,0x19,0xDC,0x03,0xF3,0x24,
0x33,0xB6,0x1E,0x57,0x5C,0xAC,0x25,0x89,0x4D,0xC5,0x9C,0x99,0x15,0x07,0xCF,0xBA,
0xC5,0x9B,0x15,0x4D,0x8D,0x2A,0x1E,0x1F,0xEA,0x2B,0x2F,0x64,0xA9,0x50,0x3D,0xAB,

0x50,0x77,0xE9,0xC0,0xAC,0x6D,0x3F,0xCA,0xCF,0x71,0x7D,0x80,0xA6,0xFD,0xFF,0xB5,
0xBD,0x6F,0x24,0x7B,0x00,0x99,0x5D,0xB1,0x48,0xB0,0x28,0x7F,0x80,0xEC,0xBF,0x6F,
0x6E,0x39,0x90,0x42,0xD9,0x4E,0x2E,0x12,0x66,0xC8,0xCF,0x3B,0x3F,0x10,0x7D,0x79,
0x00,0xD3,0x1F,0x21,0x93,0x34,0xD7,0x19,0x22,0xA2,0x08,0x20,0xB9,0xB9,0xEF,0x51,

0x99,0xDE,0xBF,0xD4,0x09,0x75,0xE9,0x8A,0xEE,0xFD,0xE4,0x4E,0x30,0x17,0xDF,0xCE,
0x11,0xB2,0x28,0x35,0xC2,0x7C,0x64,0xEB,0x91,0x5F,0x32,0x0C,0x6E,0x00,0xF9,0x92,
0x19,0xDB,0x8F,0xAB,0xAE,0xD6,0x12,0xC4,0x26,0x62,0xCE,0xCC,0x0A,0x03,0xE7,0xDD,
0xE2,0x4D,0x8A,0xA6,0x46,0x95,0x0F,0x8F,0xF5,0x15,0x97,0x32,0xD4,0x28,0x1E,0x55
};



/* struct describing a single operator */
typedef struct
{
	u32 phase;					/* accumulated operator phase */
	u32 freq;					/* operator frequency count */
	s32 dt1;					/* current DT1 (detune 1 phase inc/decrement) value */
	u32 mul;					/* frequency count multiply */
	u32 dt1_i;					/* DT1 index * 32 */
	u32 dt2;					/* current DT2 (detune 2) value */

	s32 *connect;				/* operator output 'direction' */

	/* only M1 (operator 0) is filled with this data: */
	s32 *mem_connect;			/* where to put the delayed sample (MEM) */
	s32 mem_value;				/* delayed sample (MEM) value */

	/* channel specific data; note: each operator number 0 contains channel specific data */
	u32 fb_shift;				/* feedback shift value for operators 0 in each channel */
	s32 fb_out_curr;			/* operator feedback value (used only by operators 0) */
	s32 fb_out_prev;			/* previous feedback value (used only by operators 0) */
	u32 kc;						/* channel KC (copied to all operators) */
	u32 kc_i;					/* just for speedup */
	u32 pms;					/* channel PMS */
	u32 ams;					/* channel AMS */
	/* end of channel specific data */

	u32 AMmask;					/* LFO Amplitude Modulation enable mask */
	u32 state;					/* Envelope state: 4-attack(AR) 3-decay(D1R) 2-sustain(D2R) 1-release(RR) 0-off */
	u8  eg_sh_ar;				/*  (attack state) */
	u8  eg_sel_ar;				/*  (attack state) */
	u32 tl;						/* Total attenuation Level */
	s32 volume;					/* current envelope attenuation level */
	u8  eg_sh_d1r;				/*  (decay state) */
	u8  eg_sel_d1r;				/*  (decay state) */
	u32 d1l;					/* envelope switches to sustain state after reaching this level */
	u8  eg_sh_d2r;				/*  (sustain state) */
	u8  eg_sel_d2r;				/*  (sustain state) */
	u8  eg_sh_rr;				/*  (release state) */
	u8  eg_sel_rr;				/*  (release state) */

	u32 key;					/* 0=last key was KEY OFF, 1=last key was KEY ON */

	u32 ks;						/* key scale    */
	u32 ar;						/* attack rate  */
	u32 d1r;					/* decay rate   */
	u32 d2r;					/* sustain rate */
	u32 rr;						/* release rate */

} FM_OPM;


typedef struct
{
	FM_OPM oper[32];				/* the 32 operators */

	u32 pan[8];					/* channels output masks (0xffffffff = enable) */

	u32 eg_cnt;					/* global envelope generator counter */
	u32 eg_timer;				/* global envelope generator counter works at frequency = chipclock/64/3 */
	u32 eg_timer_add;			/* step of eg_timer */
	u32 eg_timer_overflow;		/* envelope generator timer overlfows every 3 samples (on real chip) */

	u32 lfo_phase;				/* accumulated LFO phase (0 to 255) */
	u32 lfo_timer;				/* LFO timer                        */
	u32 lfo_timer_add;			/* step of lfo_timer                */
	u32 lfo_overflow;			/* LFO generates new output when lfo_timer reaches this value */
	u32 lfo_counter;			/* LFO phase increment counter      */
	u32 lfo_counter_add;		/* step of lfo_counter              */
	u8  lfo_wsel;				/* LFO waveform (0-saw, 1-square, 2-triangle, 3-random noise) */
	u8  amd;					/* LFO Amplitude Modulation Depth   */
	s8  pmd;					/* LFO Phase Modulation Depth       */
	u32 lfa;					/* LFO current AM output            */
	s32 lfp;					/* LFO current PM output            */

	u8  test;					/* TEST register */
	u8  ct;						/* output control pins (bit1-CT2, bit0-CT1) */

	u32 noise;					/* noise enable/period register (bit 7 - noise enable, bits 4-0 - noise period */
	u32 noise_rng;				/* 17 bit noise shift register */
	u32 noise_p;				/* current noise 'phase'*/
	u32 noise_f;				/* current noise period */

	u32 csm_req;				/* CSM  KEY ON / KEY OFF sequence request */

	u32 irq_enable;				/* IRQ enable for timer B (bit 3) and timer A (bit 2); bit 7 - CSM mode (keyon to all slots, everytime timer A overflows) */
	u32 status;					/* chip status (BUSY, IRQ Flags) */
	u8  connect[8];				/* channels connections */

	/* ASG 980324 -- added for tracking timers */
	float timer_A_time[1024];	/* timer A times */
	float timer_B_time[256];	/* timer B times */
	u32 timer_A_index;			/* timer A index */
	u32 timer_B_index;			/* timer B index */
	u32 timer_A_index_old;		/* timer A previous index */
	u32 timer_B_index_old;		/* timer B previous index */

	/*  Frequency-deltas to get the closest frequency possible.
    *   There are 11 octaves because of DT2 (max 950 cents over base frequency)
    *   and LFO phase modulation (max 800 cents below AND over base frequency)
    *   Summary:   octave  explanation
    *              0       note code - LFO PM
    *              1       note code
    *              2       note code
    *              3       note code
    *              4       note code
    *              5       note code
    *              6       note code
    *              7       note code
    *              8       note code
    *              9       note code + DT2 + LFO PM
    *              10      note code + DT2 + LFO PM
    */
	u32 freq[11*768];			/* 11 octaves, 768 'cents' per octave */

	/*  Frequency deltas for DT1. These deltas alter operator frequency
    *   after it has been taken from frequency-deltas table.
    */
	s32 dt1_freq[8*32];			/* 8 DT1 levels, 32 KC values */

	u32 noise_tab[32];			/* 17bit Noise Generator periods */

	FM_IRQHANDLER irqhandler;		/* IRQ function handler */

	u32 clock;					/* chip clock in Hz (passed from 2151intf.c) */
	u32 sampfreq;				/* sampling frequency in Hz (passed from 2151intf.c) */

} ym2151_t;

/* these variables stay here for speedup purposes only */
static ym2151_t ALIGN_DATA YM2151;
static ym2151_t *ym2151 = &YM2151;

static s32 ALIGN_DATA chanout[8];
static s32 m2,c1,c2; 				/* Phase Modulation input for operators 2,3,4 */
static s32 mem;					/* one sample delay memory */


#define KEY_ON(op, key_set)																\
{																						\
	if (!(op)->key)																		\
	{																					\
		int incr;																		\
		(op)->phase = 0;			/* clear phase */									\
		(op)->state = EG_ATT;		/* KEY ON = attack */								\
		incr = eg_inc[(op)->eg_sel_ar + ((ym2151->eg_cnt >> (op)->eg_sh_ar) & 7)];		\
		(op)->volume += (~(op)->volume * incr) >> 4;									\
		if ((op)->volume <= MIN_ATT_INDEX)												\
		{																				\
			(op)->volume = MIN_ATT_INDEX;												\
			(op)->state = EG_DEC;														\
		}																				\
	}																					\
	(op)->key |= key_set;																\
}

#define KEY_OFF(op, key_clr)															\
{																						\
	if ((op)->key)																		\
	{																					\
		(op)->key &= key_clr;															\
		if (!(op)->key)																	\
		{																				\
			if ((op)->state>EG_REL)														\
				(op)->state = EG_REL;/* KEY OFF = release */							\
		}																				\
	}																					\
}



static void init_tables(void)
{
	s32 i, x, 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 closest */
			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];
		}
	}

	for (i = 0; i < SIN_LEN; i++)
	{
		/* non-standard sinus */
		m = sin(((i * 2) + 1) * PI / SIN_LEN); /* verified on the real chip */

		/* we never reach zero here due to ((i*2)+1) */

		if (m > 0.0)
			o = 8*log(1.0/m)/log(2);	/* convert to 'decibels' */
		else
			o = 8*log(-1.0/m)/log(2);	/* convert to 'decibels' */

		o = o / (ENV_STEP/4);

		n = (int)(2.0*o);
		if (n & 1)						/* round to closest */
			n = (n >> 1) + 1;
		else
			n = n >> 1;

		sin_tab[i] = n * 2 + (m >= 0.0 ? 0 : 1);
	}

	/* calculate d1l_tab table */
	for (i=0; i<16; i++)
	{
		m = (i!=15 ? i : i+16) * (4.0/ENV_STEP);   /* every 3 'dB' except for all bits = 1 = 45+48 'dB' */
		d1l_tab[i] = m;
	}
}


static void init_chip_tables(void)
{
	int i,j;
	double mult,pom,phaseinc,Hz;
	double scaler;

	scaler = ((double)ym2151->clock / 64.0) / ((double)ym2151->sampfreq);

	/* this loop calculates Hertz values for notes from c-0 to b-7 */
	/* including 64 'cents' (100/64 that is 1.5625 of real cent) per note */
	/* i*100/64/1200 is equal to i/768 */

	/* real chip works with 10 bits fixed point values (10.10) */
	mult = (1<<(FREQ_SH-10)); /* -10 because phaseinc_rom table values are already in 10.10 format */

	for (i = 0; i < 768; i++)
	{
		/* 3.4375 Hz is note A; C# is 4 semitones higher */
		Hz = 1000;

		phaseinc = phaseinc_rom[i];	/* real chip phase increment */
		phaseinc *= scaler;			/* adjust */


		/* octave 2 - reference octave */
		ym2151->freq[768+2*768+i] = ((int)(phaseinc*mult)) & 0xffffffc0; /* adjust to X.10 fixed point */
		/* octave 0 and octave 1 */
		for (j=0; j<2; j++)
		{
			ym2151->freq[768 + j*768 + i] = (ym2151->freq[768+2*768+i] >> (2-j)) & 0xffffffc0; /* adjust to X.10 fixed point */
		}
		/* octave 3 to 7 */
		for (j=3; j<8; j++)
		{
			ym2151->freq[768 + j*768 + i] = ym2151->freq[768+2*768+i] << (j-2);
		}
	}

	/* octave -1 (all equal to: oct 0, _KC_00_, _KF_00_) */
	for (i=0; i<768; i++)
	{
		ym2151->freq[0*768 + i] = ym2151->freq[1*768+0];
	}

	/* octave 8 and 9 (all equal to: oct 7, _KC_14_, _KF_63_) */
	for (j=8; j<10; j++)
	{
		for (i=0; i<768; i++)
		{
			ym2151->freq[768+ j*768 + i] = ym2151->freq[768 + 8*768 -1];
		}
	}

	mult = (1<<FREQ_SH);
	for (j=0; j<4; j++)
	{
		for (i=0; i<32; i++)
		{
			Hz = ((double)dt1_tab[j*32+i] * ((double)ym2151->clock/64.0)) / (double)(1<<20);

			/*calculate phase increment*/
			phaseinc = (Hz*SIN_LEN) / (double)ym2151->sampfreq;

			/*positive and negative values*/
			ym2151->dt1_freq[(j+0)*32 + i] = phaseinc * mult;
			ym2151->dt1_freq[(j+4)*32 + i] = -ym2151->dt1_freq[(j+0)*32 + i];
		}
	}


	/* calculate timers' deltas */
	/* User's Manual pages 15,16  */
	mult = (1<<TIMER_SH);
	for (i=0; i<1024; i++)
	{
		/* ASG 980324: changed to compute both tim_A_tab and timer_A_time */
		pom= (64.0  *  (1024.0-i) / (double)ym2151->clock);
		ym2151->timer_A_time[i] = (float)SEC_TO_USEC(pom);
	}
	for (i=0; i<256; i++)
	{
		/* ASG 980324: changed to compute both tim_B_tab and timer_B_time */
		pom= (1024.0 * (256.0-i)  / (double)ym2151->clock);
		ym2151->timer_B_time[i] = (float)SEC_TO_USEC(pom);
	}

	/* calculate noise periods table */
	scaler = ((double)ym2151->clock / 64.0) / ((double)ym2151->sampfreq);
	for (i=0; i<32; i++)
	{
		j = (i!=31 ? i : 30);				/* rate 30 and 31 are the same */
		j = 32-j;
		j = (65536.0 / (double)(j*32.0));	/* number of samples per one shift of the shift register */
		/*ym2151->noise_tab[i] = j * 64;*/	/* number of chip clock cycles per one shift */
		ym2151->noise_tab[i] = j * 64 * scaler;
		/*logerror("noise_tab[%02x]=%08x\n", i, ym2151->noise_tab[i]);*/
	}
}

static void envelope_KONKOFF(FM_OPM *op, int v)
{
	if (v & 0x08)	/* M1 */
		KEY_ON (op+0, 1)
	else
		KEY_OFF(op+0,~1)

	if (v & 0x20)	/* M2 */
		KEY_ON (op+1, 1)
	else
		KEY_OFF(op+1,~1)

	if (v & 0x10)	/* C1 */
		KEY_ON (op+2, 1)
	else
		KEY_OFF(op+2,~1)

	if (v & 0x40)	/* C2 */
		KEY_ON (op+3, 1)
	else
		KEY_OFF(op+3,~1)
}


void timer_callback_2151_a(int param)
{
	timer_adjust(YM2151_TIMERA, ym2151->timer_A_time[ym2151->timer_A_index], 0, timer_callback_2151_a);
	ym2151->timer_A_index_old = ym2151->timer_A_index;

	if (ym2151->irq_enable & 0x04)
	{
		int oldstate = ym2151->status & 3;

		ym2151->status |= 1;
		if (!oldstate) (*ym2151->irqhandler)(1);
	}
	if (ym2151->irq_enable & 0x80)
		ym2151->csm_req = 2;		/* request KEY ON / KEY OFF sequence */
}

void timer_callback_2151_b(int param)
{
	timer_adjust(YM2151_TIMERB, ym2151->timer_B_time[ym2151->timer_B_index], 0, timer_callback_2151_b);
	ym2151->timer_B_index_old = ym2151->timer_B_index;

	if (ym2151->irq_enable & 0x08)
	{
		int oldstate = ym2151->status & 3;

		ym2151->status |= 2;
		if (!oldstate) (*ym2151->irqhandler)(1);
	}
}


static void set_connect(FM_OPM *om1, int ch, int v)
{
	FM_OPM *om2 = om1 + 1;
	FM_OPM *oc1 = om1 + 2;

	/* set connect algorithm */

	/* MEM is simply one sample delay */

	switch (v & 7)
	{
	case 0:
		/* M1---C1---MEM---M2---C2---OUT */
		om1->connect = &c1;
		oc1->connect = &mem;
		om2->connect = &c2;
		om1->mem_connect = &m2;
		break;

	case 1:
		/* M1------+-MEM---M2---C2---OUT */
		/*      C1-+                     */
		om1->connect = &mem;
		oc1->connect = &mem;
		om2->connect = &c2;
		om1->mem_connect = &m2;
		break;

	case 2:
		/* M1-----------------+-C2---OUT */
		/*      C1---MEM---M2-+          */
		om1->connect = &c2;
		oc1->connect = &mem;
		om2->connect = &c2;
		om1->mem_connect = &m2;
		break;

	case 3:
		/* M1---C1---MEM------+-C2---OUT */
		/*                 M2-+          */
		om1->connect = &c1;
		oc1->connect = &mem;
		om2->connect = &c2;
		om1->mem_connect = &c2;
		break;

	case 4:
		/* M1---C1-+-OUT */
		/* M2---C2-+     */
		/* MEM: not used */
		om1->connect = &c1;
		oc1->connect = &chanout[ch];
		om2->connect = &c2;
		om1->mem_connect = &mem;	/* store it anywhere where it will not be used */
		break;

	case 5:
		/*    +----C1----+     */
		/* M1-+-MEM---M2-+-OUT */
		/*    +----C2----+     */
		om1->connect = 0;	/* special mark */
		oc1->connect = &chanout[ch];
		om2->connect = &chanout[ch];
		om1->mem_connect = &m2;
		break;

	case 6:
		/* M1---C1-+     */
		/*      M2-+-OUT */
		/*      C2-+     */
		/* MEM: not used */
		om1->connect = &c1;
		oc1->connect = &chanout[ch];
		om2->connect = &chanout[ch];
		om1->mem_connect = &mem;	/* store it anywhere where it will not be used */
		break;

	case 7:
		/* M1-+     */
		/* C1-+-OUT */
		/* M2-+     */
		/* C2-+     */
		/* MEM: not used*/
		om1->connect = &chanout[ch];
		oc1->connect = &chanout[ch];
		om2->connect = &chanout[ch];
		om1->mem_connect = &mem;	/* store it anywhere where it will not be used */
		break;
	}
}


static void refresh_EG(FM_OPM *op)
{
	u32 kc;
	u32 v;

	kc = op->kc;

	/* v = 32 + 2*RATE + RKS = max 126 */

	v = kc >> op->ks;
	if ((op->ar+v) < 32+62)
	{
		op->eg_sh_ar  = eg_rate_shift [op->ar  + v];
		op->eg_sel_ar = eg_rate_select[op->ar  + v];
	}
	else
	{
		op->eg_sh_ar  = 0;
		op->eg_sel_ar = 17*RATE_STEPS;
	}
	op->eg_sh_d1r = eg_rate_shift [op->d1r + v];
	op->eg_sel_d1r= eg_rate_select[op->d1r + v];
	op->eg_sh_d2r = eg_rate_shift [op->d2r + v];
	op->eg_sel_d2r= eg_rate_select[op->d2r + v];
	op->eg_sh_rr  = eg_rate_shift [op->rr  + v];
	op->eg_sel_rr = eg_rate_select[op->rr  + v];


	op+=1;

	v = kc >> op->ks;
	if ((op->ar+v) < 32+62)
	{
		op->eg_sh_ar  = eg_rate_shift [op->ar  + v];
		op->eg_sel_ar = eg_rate_select[op->ar  + v];
	}
	else
	{
		op->eg_sh_ar  = 0;
		op->eg_sel_ar = 17*RATE_STEPS;
	}
	op->eg_sh_d1r = eg_rate_shift [op->d1r + v];
	op->eg_sel_d1r= eg_rate_select[op->d1r + v];
	op->eg_sh_d2r = eg_rate_shift [op->d2r + v];
	op->eg_sel_d2r= eg_rate_select[op->d2r + v];
	op->eg_sh_rr  = eg_rate_shift [op->rr  + v];
	op->eg_sel_rr = eg_rate_select[op->rr  + v];

	op+=1;

	v = kc >> op->ks;
	if ((op->ar+v) < 32+62)
	{
		op->eg_sh_ar  = eg_rate_shift [op->ar  + v];
		op->eg_sel_ar = eg_rate_select[op->ar  + v];
	}
	else
	{
		op->eg_sh_ar  = 0;
		op->eg_sel_ar = 17*RATE_STEPS;
	}
	op->eg_sh_d1r = eg_rate_shift [op->d1r + v];
	op->eg_sel_d1r= eg_rate_select[op->d1r + v];
	op->eg_sh_d2r = eg_rate_shift [op->d2r + v];
	op->eg_sel_d2r= eg_rate_select[op->d2r + v];
	op->eg_sh_rr  = eg_rate_shift [op->rr  + v];
	op->eg_sel_rr = eg_rate_select[op->rr  + v];

	op+=1;

	v = kc >> op->ks;
	if ((op->ar+v) < 32+62)
	{
		op->eg_sh_ar  = eg_rate_shift [op->ar  + v];
		op->eg_sel_ar = eg_rate_select[op->ar  + v];
	}
	else
	{
		op->eg_sh_ar  = 0;
		op->eg_sel_ar = 17*RATE_STEPS;
	}
	op->eg_sh_d1r = eg_rate_shift [op->d1r + v];
	op->eg_sel_d1r= eg_rate_select[op->d1r + v];
	op->eg_sh_d2r = eg_rate_shift [op->d2r + v];
	op->eg_sel_d2r= eg_rate_select[op->d2r + v];
	op->eg_sh_rr  = eg_rate_shift [op->rr  + v];
	op->eg_sel_rr = eg_rate_select[op->rr  + v];
}


/* write a register on YM2151 chip number 'n' */
void YM2151WriteReg(int r, int v)
{
	FM_OPM *op = &ym2151->oper[((r & 7) << 2) + ((r & 0x18) >> 3)];

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

	switch (r & 0xe0)
	{
	case 0x00:
		switch(r)
		{
		case 0x01:	/* LFO reset(bit 1), Test Register (other bits) */
			ym2151->test = v;
			if (v&2) ym2151->lfo_phase = 0;
			break;

		case 0x08:
			envelope_KONKOFF(&ym2151->oper[(v & 7) << 2], v);
			break;

		case 0x0f:	/* noise mode enable, noise period */
			ym2151->noise = v;
			ym2151->noise_f = ym2151->noise_tab[v & 0x1f];
			break;

		case 0x10:	/* timer A hi */
			ym2151->timer_A_index = (ym2151->timer_A_index & 0x003) | (v << 2);
			break;

		case 0x11:	/* timer A low */
			ym2151->timer_A_index = (ym2151->timer_A_index & 0x3fc) | (v & 3);
			break;

		case 0x12:	/* timer B */
			ym2151->timer_B_index = v;
			break;

		case 0x14:	/* CSM, irq flag reset, irq enable, timer start/stop */

			ym2151->irq_enable = v;	/* bit 3-timer B, bit 2-timer A, bit 7 - CSM */

			if (v & 0x20)	/* reset timer B irq flag */
			{
				int oldstate = ym2151->status & 3;

				ym2151->status &= 0xfd;
				if (oldstate == 2) (*ym2151->irqhandler)(0);
			}

			if (v & 0x10)	/* reset timer A irq flag */
			{
				int oldstate = ym2151->status & 3;

				ym2151->status &= 0xfe;
				if (oldstate == 1) (*ym2151->irqhandler)(0);
			}

			if (v & 0x02)	/* load and start timer B */
			{
				/* ASG 980324: added a real timer */
				/* start timer _only_ if it wasn't already started (it will reload time value next round) */
				if (!timer_enable(YM2151_TIMERB, 1))
				{
					timer_adjust(YM2151_TIMERB, ym2151->timer_B_time[ym2151->timer_B_index], 0, timer_callback_2151_b);
					ym2151->timer_B_index_old = ym2151->timer_B_index;
				}
			}
			else	/* stop timer B */
			{
				/* ASG 980324: added a real timer */
				timer_enable(YM2151_TIMERB, 0);
			}

			if (v & 0x01)	/* load and start timer A */
			{
				if (!timer_enable(YM2151_TIMERA, 1))
				{
					timer_adjust(YM2151_TIMERA, ym2151->timer_A_time[ym2151->timer_A_index], 0, timer_callback_2151_a);
					ym2151->timer_A_index_old = ym2151->timer_A_index;
				}
			}
			else	/* stop timer A */
			{
				/* ASG 980324: added a real timer */
				timer_enable(YM2151_TIMERA, 0);
			}
			break;

		case 0x18:	/* LFO frequency */
			ym2151->lfo_overflow    = (1 << ((15 - (v >> 4)) + 3)) << LFO_SH;
			ym2151->lfo_counter_add = 0x10 + (v & 0x0f);
			break;

		case 0x19:	/* PMD (bit 7==1) or AMD (bit 7==0) */
			if (v & 0x80)
				ym2151->pmd = v & 0x7f;
			else
				ym2151->amd = v & 0x7f;
			break;

		case 0x1b:	/* CT2, CT1, LFO waveform */
			ym2151->ct = v >> 6;
			ym2151->lfo_wsel = v & 3;
			break;

		default:
//			logerror("YM2151 Write %02x to undocumented register #%02x\n",v,r);
			break;
		}
		break;

	case 0x20:
		op = &ym2151->oper[(r & 7) << 2];
		switch (r & 0x18)
		{
		case 0x00:	/* RL enable, Feedback, Connection */
			op->fb_shift = ((v >> 3) & 7) ? ((v >> 3) & 7) + 6 : 0;
#if 0
			ym2151->pan[(r&7)*2   ] = (v & 0x40) ? ~0 : 0;
			ym2151->pan[(r&7)*2 +1] = (v & 0x80) ? ~0 : 0;
#else
			ym2151->pan[r & 7] = (v & 0xc0) ? ~0 : 0;
#endif
			ym2151->connect[r & 7] = v & 7;
			set_connect(op, r & 7, v & 7);
			break;

		case 0x08:	/* Key Code */
			v &= 0x7f;
			if (v != op->kc)
			{
				u32 kc, kc_channel;

				kc_channel = (v - (v >> 2)) << 6;
				kc_channel += 768;
				kc_channel |= (op->kc_i & 63);

				(op+0)->kc = v;
				(op+0)->kc_i = kc_channel;
				(op+1)->kc = v;
				(op+1)->kc_i = kc_channel;
				(op+2)->kc = v;
				(op+2)->kc_i = kc_channel;
				(op+3)->kc = v;
				(op+3)->kc_i = kc_channel;

				kc = v>>2;

				(op+0)->dt1 = ym2151->dt1_freq[(op+0)->dt1_i + kc];
				(op+0)->freq = ((ym2151->freq[kc_channel + (op+0)->dt2] + (op+0)->dt1) * (op+0)->mul) >> 1;

				(op+1)->dt1 = ym2151->dt1_freq[(op+1)->dt1_i + kc];
				(op+1)->freq = ((ym2151->freq[kc_channel + (op+1)->dt2] + (op+1)->dt1) * (op+1)->mul) >> 1;

				(op+2)->dt1 = ym2151->dt1_freq[(op+2)->dt1_i + kc];
				(op+2)->freq = ((ym2151->freq[kc_channel + (op+2)->dt2] + (op+2)->dt1) * (op+2)->mul) >> 1;

				(op+3)->dt1 = ym2151->dt1_freq[(op+3)->dt1_i + kc];
				(op+3)->freq = ((ym2151->freq[kc_channel + (op+3)->dt2] + (op+3)->dt1) * (op+3)->mul) >> 1;

				refresh_EG(op);
			}
			break;

		case 0x10:	/* Key Fraction */
			v >>= 2;
			if (v !=  (op->kc_i & 63))
			{
				u32 kc_channel;

				kc_channel = v;
				kc_channel |= (op->kc_i & ~63);

				(op+0)->kc_i = kc_channel;
				(op+1)->kc_i = kc_channel;
				(op+2)->kc_i = kc_channel;
				(op+3)->kc_i = kc_channel;

				(op+0)->freq = ((ym2151->freq[kc_channel + (op+0)->dt2] + (op+0)->dt1) * (op+0)->mul) >> 1;
				(op+1)->freq = ((ym2151->freq[kc_channel + (op+1)->dt2] + (op+1)->dt1) * (op+1)->mul) >> 1;
				(op+2)->freq = ((ym2151->freq[kc_channel + (op+2)->dt2] + (op+2)->dt1) * (op+2)->mul) >> 1;
				(op+3)->freq = ((ym2151->freq[kc_channel + (op+3)->dt2] + (op+3)->dt1) * (op+3)->mul) >> 1;
			}
			break;

		case 0x18:	/* PMS, AMS */
			op->pms = (v>>4) & 7;
			op->ams = (v & 3);
			break;
		}
		break;

	case 0x40:		/* DT1, MUL */
		{
			u32 olddt1_i = op->dt1_i;
			u32 oldmul = op->mul;

			op->dt1_i = (v&0x70)<<1;
			op->mul   = (v&0x0f) ? (v&0x0f)<<1: 1;

			if (olddt1_i != op->dt1_i)
				op->dt1 = ym2151->dt1_freq[op->dt1_i + (op->kc>>2)];

			if ((olddt1_i != op->dt1_i) || (oldmul != op->mul))
				op->freq = ((ym2151->freq[op->kc_i + op->dt2] + op->dt1) * op->mul) >> 1;
		}
		break;

	case 0x60:		/* TL */
		op->tl = (v&0x7f)<<(ENV_BITS-7); /* 7bit TL */
		break;

	case 0x80:		/* KS, AR */
		{
			u32 oldks = op->ks;
			u32 oldar = op->ar;

			op->ks = 5-(v>>6);
			op->ar = (v&0x1f) ? 32 + ((v&0x1f)<<1) : 0;

			if ((op->ar != oldar) || (op->ks != oldks))
			{
				if ((op->ar + (op->kc>>op->ks)) < 32+62)
				{
					op->eg_sh_ar  = eg_rate_shift [op->ar  + (op->kc>>op->ks)];
					op->eg_sel_ar = eg_rate_select[op->ar  + (op->kc>>op->ks)];
				}
				else
				{
					op->eg_sh_ar  = 0;
					op->eg_sel_ar = 17*RATE_STEPS;
				}
			}

			if (op->ks != oldks)
			{
				op->eg_sh_d1r = eg_rate_shift [op->d1r + (op->kc>>op->ks)];
				op->eg_sel_d1r= eg_rate_select[op->d1r + (op->kc>>op->ks)];
				op->eg_sh_d2r = eg_rate_shift [op->d2r + (op->kc>>op->ks)];
				op->eg_sel_d2r= eg_rate_select[op->d2r + (op->kc>>op->ks)];
				op->eg_sh_rr  = eg_rate_shift [op->rr  + (op->kc>>op->ks)];
				op->eg_sel_rr = eg_rate_select[op->rr  + (op->kc>>op->ks)];
			}
		}
		break;

	case 0xa0:		/* LFO AM enable, D1R */
		op->AMmask = (v&0x80) ? ~0 : 0;
		op->d1r    = (v&0x1f) ? 32 + ((v&0x1f)<<1) : 0;
		op->eg_sh_d1r = eg_rate_shift [op->d1r + (op->kc>>op->ks)];
		op->eg_sel_d1r= eg_rate_select[op->d1r + (op->kc>>op->ks)];
		break;

	case 0xc0:		/* DT2, D2R */
		{
			u32 olddt2 = op->dt2;
			op->dt2 = dt2_tab[v>>6];
			if (op->dt2 != olddt2)
				op->freq = ((ym2151->freq[op->kc_i + op->dt2] + op->dt1) * op->mul) >> 1;
		}
		op->d2r = (v&0x1f) ? 32 + ((v&0x1f)<<1) : 0;
		op->eg_sh_d2r = eg_rate_shift [op->d2r + (op->kc>>op->ks)];
		op->eg_sel_d2r= eg_rate_select[op->d2r + (op->kc>>op->ks)];
		break;

	case 0xe0:		/* D1L, RR */
		op->d1l = d1l_tab[v>>4];
		op->rr  = 34 + ((v&0x0f)<<2);
		op->eg_sh_rr  = eg_rate_shift [op->rr  + (op->kc>>op->ks)];
		op->eg_sel_rr = eg_rate_select[op->rr  + (op->kc>>op->ks)];
		break;
	}
}


int YM2151ReadStatus(void)
{
	return ym2151->status;
}


#define volume_calc(OP) ((OP)->tl + ((u32)(OP)->volume) + (AM & (OP)->AMmask))


INLINE s32 op_calc(FM_OPM *OP, u32 env, s32 pm)
{
	u32 p = (env << 3) + sin_tab[(((s32)((OP->phase & ~FREQ_MASK) + (pm << 15))) >> FREQ_SH) & SIN_MASK];

	if (p >= TL_TAB_LEN)
		return 0;

	return tl_tab[p];
}

INLINE s32 op_calc1(FM_OPM *OP, u32 env, s32 pm)
{
	u32 p = (env << 3) + sin_tab[(((s32)((OP->phase & ~FREQ_MASK) + pm)) >> FREQ_SH) & SIN_MASK];

	if (p >= TL_TAB_LEN)
		return 0;

	return tl_tab[p];
}

static void chan_calc(u32 chan)
{
	FM_OPM *op;
	u32 env;
	u32 AM = 0;

	m2 = c1 = c2 = mem = 0;
	op = &ym2151->oper[chan << 2];	/* M1 */

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

	if (op->ams)
		AM = ym2151->lfa << (op->ams-1);
	env = volume_calc(op);
	{
		s32 out = op->fb_out_prev + op->fb_out_curr;
		op->fb_out_prev = op->fb_out_curr;

		if (!op->connect)
			/* algorithm 5 */
			mem = c1 = c2 = op->fb_out_prev;
		else
			/* other algorithms */
			*op->connect = op->fb_out_prev;

		op->fb_out_curr = 0;
		if (env < ENV_QUIET)
		{
			if (!op->fb_shift)
				out = 0;
			op->fb_out_curr = op_calc1(op, env, out << op->fb_shift);
		}
	}

	env = volume_calc(op + 1);	/* M2 */
	if (env < ENV_QUIET)
		*(op + 1)->connect += op_calc(op + 1, env, m2);

	env = volume_calc(op + 2);	/* C1 */
	if (env < ENV_QUIET)
		*(op + 2)->connect += op_calc(op + 2, env, c1);

	env = volume_calc(op + 3);	/* C2 */
	if (env < ENV_QUIET)
		chanout[chan] += op_calc(op + 3, env, c2);

	/* M1 */
	op->mem_value = mem;
}


static void chan7_calc(void)
{
	FM_OPM *op;
	u32 env;
	u32 AM = 0;

	m2 = c1 = c2 = mem = 0;
	op = &ym2151->oper[7 * 4];		/* M1 */

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

	if (op->ams)
		AM = ym2151->lfa << (op->ams - 1);
	env = volume_calc(op);
	{
		s32 out = op->fb_out_prev + op->fb_out_curr;
		op->fb_out_prev = op->fb_out_curr;

		if (!op->connect)
			/* algorithm 5 */
			mem = c1 = c2 = op->fb_out_prev;
		else
			/* other algorithms */
			*op->connect = op->fb_out_prev;

		op->fb_out_curr = 0;
		if (env < ENV_QUIET)
		{
			if (!op->fb_shift)
				out = 0;
			op->fb_out_curr = op_calc1(op, env, out << op->fb_shift);
		}
	}

	env = volume_calc(op + 1);	/* M2 */
	if (env < ENV_QUIET)
		*(op + 1)->connect += op_calc(op + 1, env, m2);

	env = volume_calc(op + 2);	/* C1 */
	if (env < ENV_QUIET)
		*(op + 2)->connect += op_calc(op + 2, env, c1);

	env = volume_calc(op + 3);	/* C2 */
	if (ym2151->noise & 0x80)
	{
		u32 noiseout;

		noiseout = 0;
		if (env < 0x3ff)
			noiseout = (env ^ 0x3ff) << 1;	/* range of the YM2151 noise output is -2044 to 2040 */
		chanout[7] += ((ym2151->noise_rng & 0x10000) ? noiseout: -noiseout); /* bit 16 -> output */
	}
	else
	{
		if (env < ENV_QUIET)
			chanout[7] += op_calc(op + 3, env, c2);
	}
	/* M1 */
	op->mem_value = mem;
}


static void advance_eg(void)
{
	FM_OPM *op;
	u32 i;

	ym2151->eg_timer += ym2151->eg_timer_add;

	while (ym2151->eg_timer >= ym2151->eg_timer_overflow)
	{
		ym2151->eg_timer -= ym2151->eg_timer_overflow;

		ym2151->eg_cnt++;

		/* envelope generator */
		op = &ym2151->oper[0];	/* CH 0 M1 */
		i = 32;
		do
		{
			switch (op->state)
			{
			case EG_ATT:	/* attack phase */
				if (!(ym2151->eg_cnt & ((1 << op->eg_sh_ar) - 1)))
				{
					op->volume += (~op->volume * (eg_inc[op->eg_sel_ar + ((ym2151->eg_cnt >> op->eg_sh_ar) & 7)])) >> 4;

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

			case EG_DEC:	/* decay phase */
				if (!(ym2151->eg_cnt & ((1 << op->eg_sh_d1r) - 1)))
				{
					op->volume += eg_inc[op->eg_sel_d1r + ((ym2151->eg_cnt >> op->eg_sh_d1r) & 7)];

					if (op->volume >= op->d1l)
						op->state = EG_SUS;
				}
				break;

			case EG_SUS:	/* sustain phase */
				if (!(ym2151->eg_cnt & ((1 << op->eg_sh_d2r) - 1)))
				{
					op->volume += eg_inc[op->eg_sel_d2r + ((ym2151->eg_cnt >> op->eg_sh_d2r) & 7)];

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

			case EG_REL:	/* release phase */
				if (!(ym2151->eg_cnt & ((1 << op->eg_sh_rr) - 1)))
				{
					op->volume += eg_inc[op->eg_sel_rr + ((ym2151->eg_cnt >> op->eg_sh_rr) & 7)];

					if (op->volume >= MAX_ATT_INDEX)
					{
						op->volume = MAX_ATT_INDEX;
						op->state = EG_OFF;
					}
				}
				break;
			}
			op++;
			i--;
		} while (i);
	}
}


static void advance(void)
{
	FM_OPM *op;
	u32 i;
	int a,p;

	/* LFO */
	if (ym2151->test & 2)
		ym2151->lfo_phase = 0;
	else
	{
		ym2151->lfo_timer += ym2151->lfo_timer_add;
		if (ym2151->lfo_timer >= ym2151->lfo_overflow)
		{
			ym2151->lfo_timer   -= ym2151->lfo_overflow;
			ym2151->lfo_counter += ym2151->lfo_counter_add;
			ym2151->lfo_phase   += ym2151->lfo_counter >> 4;
			ym2151->lfo_phase   &= 255;
			ym2151->lfo_counter &= 15;
		}
	}

	i = ym2151->lfo_phase;
	/* calculate LFO AM and PM waveform value (all verified on real chip, except for noise algorithm which is impossible to analyse)*/
	switch (ym2151->lfo_wsel)
	{
	case 0:
		/* saw */
		/* AM: 255 down to 0 */
		/* PM: 0 to 127, -127 to 0 (at PMD=127: LFP = 0 to 126, -126 to 0) */
		a = 255 - i;
		p = (i < 128) ? p = i : i - 255;
		break;

	case 1:
		/* square */
		/* AM: 255, 0 */
		/* PM: 128,-128 (LFP = exactly +PMD, -PMD) */
		if (i < 128){
			a = 255;
			p = 128;
		}else{
			a = 0;
			p = -128;
		}
		break;

	case 2:
		/* triangle */
		/* AM: 255 down to 1 step -2; 0 up to 254 step +2 */
		/* PM: 0 to 126 step +2, 127 to 1 step -2, 0 to -126 step -2, -127 to -1 step +2*/
		a = (i < 128) ? 255 - (i << 1) : (i << 1) - 256;

		if (i < 64)					/* i = 0..63 */
			p = i << 1;				/* 0 to 126 step +2 */
		else if (i < 128)			/* i = 64..127 */
			p = 255 - (i << 1);		/* 127 to 1 step -2 */
		else if (i < 192)			/* i = 128..191 */
			p = 256 - (i << 1);		/* 0 to -126 step -2*/
		else						/* i = 192..255 */
			p = (i << 1) - 511;		/*-127 to -1 step +2*/
		break;

	case 3:
	default:	/*keep the compiler happy*/
		/* random */
		/* the real algorithm is unknown !!!
            We just use a snapshot of data from real chip */

		/* AM: range 0 to 255    */
		/* PM: range -128 to 127 */

		a = lfo_noise_waveform[i];
		p = a - 128;
		break;
	}
	ym2151->lfa = a * ym2151->amd >> 7;
	ym2151->lfp = p * ym2151->pmd >> 7;

	/*  The Noise Generator of the YM2151 is 17-bit shift register.
    *   Input to the bit16 is negated (bit0 XOR bit3) (EXNOR).
    *   Output of the register is negated (bit0 XOR bit3).
    *   Simply use bit16 as the noise output.
    */
	ym2151->noise_p += ym2151->noise_f;
	i = (ym2151->noise_p >> 16);	/* number of events (shifts of the shift register) */
	ym2151->noise_p &= 0xffff;
	while (i)
	{
		u32 j;
		j = ((ym2151->noise_rng ^ (ym2151->noise_rng >> 3)) & 1) ^ 1;
		ym2151->noise_rng = (j << 16) | (ym2151->noise_rng >> 1);
		i--;
	}


	/* phase generator */
	op = &ym2151->oper[0];	/* CH 0 M1 */
	i = 8;
	do
	{
		if (op->pms)	/* only when phase modulation from LFO is enabled for this channel */
		{
			s32 mod_ind = ym2151->lfp;		/* -128..+127 (8bits signed) */
			if (op->pms < 6)
				mod_ind >>= (6 - op->pms);
			else
				mod_ind <<= (op->pms - 5);

			if (mod_ind)
			{
				u32 kc_channel =	op->kc_i + mod_ind;
				(op + 0)->phase += ((ym2151->freq[kc_channel + (op + 0)->dt2] + (op + 0)->dt1) * (op + 0)->mul) >> 1;
				(op + 1)->phase += ((ym2151->freq[kc_channel + (op + 1)->dt2] + (op + 1)->dt1) * (op + 1)->mul) >> 1;
				(op + 2)->phase += ((ym2151->freq[kc_channel + (op + 2)->dt2] + (op + 2)->dt1) * (op + 2)->mul) >> 1;
				(op + 3)->phase += ((ym2151->freq[kc_channel + (op + 3)->dt2] + (op + 3)->dt1) * (op + 3)->mul) >> 1;
			}
			else		/* phase modulation from LFO is equal to zero */
			{
				(op + 0)->phase += (op + 0)->freq;
				(op + 1)->phase += (op + 1)->freq;
				(op + 2)->phase += (op + 2)->freq;
				(op + 3)->phase += (op + 3)->freq;
			}
		}
		else			/* phase modulation from LFO is disabled */
		{
			(op + 0)->phase += (op + 0)->freq;
			(op + 1)->phase += (op + 1)->freq;
			(op + 2)->phase += (op + 2)->freq;
			(op + 3)->phase += (op + 3)->freq;
		}

		op += 4;
		i--;
	} while (i);


	/* CSM is calculated *after* the phase generator calculations (verified on real chip)
    * CSM keyon line seems to be ORed with the KO line inside of the chip.
    * The result is that it only works when KO (register 0x08) is off, ie. 0
    *
    * Interesting effect is that when timer A is set to 1023, the KEY ON happens
    * on every sample, so there is no KEY OFF at all - the result is that
    * the sound played is the same as after normal KEY ON.
    */

	if (ym2151->csm_req)			/* CSM KEYON/KEYOFF seqeunce request */
	{
		if (ym2151->csm_req == 2)	/* KEY ON */
		{
			op = &ym2151->oper[0];	/* CH 0 M1 */
			i = 32;
			do
			{
				KEY_ON(op, 2);
				op++;
				i--;
			} while (i);
			ym2151->csm_req = 1;
		}
		else					/* KEY OFF */
		{
			op = &ym2151->oper[0];	/* CH 0 M1 */
			i = 32;
			do
			{
				KEY_OFF(op, ~2);
				op++;
				i--;
			} while (i);
			ym2151->csm_req = 0;
		}
	}
}


static void YM2151Update_stream(s16 *mixing_buffer, int length)
{
	int i, j;
	FMSAMPLE_MIX out;

	if (okim6295->rom_base) OKIM6295Update(length);

	for (i = 0; i < length; i++)
	{
		advance_eg();

		chanout[0] = 0;
		chanout[1] = 0;
		chanout[2] = 0;
		chanout[3] = 0;
		chanout[4] = 0;
		chanout[5] = 0;
		chanout[6] = 0;
		chanout[7] = 0;

		chan_calc(0);
		chan_calc(1);
		chan_calc(2);
		chan_calc(3);
		chan_calc(4);
		chan_calc(5);
		chan_calc(6);
		chan7_calc();

		out = 0;
		for (j = 0; j < 8; j++)
			out += (chanout[j] & ym2151->pan[j]) << 1;

		out += okim6295->buffer[i];

		Limit(out, MAXOUT, MINOUT);

		mixing_buffer[i] = out;

		advance();
	}
}

void YM2151Update(int p)
{
	int i;
	s16 v, *buffer = (s16 *)p;
	s16 mixing_buffer[SOUND_SAMPLES];

	switch (option_samplerate)
	{
	case 0:
		YM2151Update_stream(mixing_buffer, SOUND_SAMPLES >> 2);
		for (i = 0; i < SOUND_SAMPLES >> 2; i++)
		{
			v = mixing_buffer[i];
			*buffer++ = v;
			*buffer++ = v;
			*buffer++ = v;
			*buffer++ = v;
		}
		break;

	case 1:
		YM2151Update_stream(mixing_buffer, SOUND_SAMPLES >> 1);
		for (i = 0; i < SOUND_SAMPLES >> 1; i++)
		{
			v = mixing_buffer[i];
			*buffer++ = v;
			*buffer++ = v;
		}
		break;

	case 2:
		YM2151Update_stream(mixing_buffer, SOUND_SAMPLES);
		for (i = 0; i < SOUND_SAMPLES; i++)
		{
			*buffer++ = mixing_buffer[i];
		}
		break;
	}
}


void YM2151Init(int clock, int rate, FM_IRQHANDLER IRQHandler)
{
	sound->stack    = 0x10000;
	sound->stereo   = 0;
	sound->callback = YM2151Update;

	memset(ym2151, 0, sizeof(ym2151_t));

	ym2151->clock      = clock;
	ym2151->sampfreq   = rate;
	ym2151->irqhandler = IRQHandler;

	init_tables();
	init_chip_tables();

	ym2151->lfo_timer_add = (1<<LFO_SH) * (clock/64.0) / ym2151->sampfreq;

	ym2151->eg_timer_add  = (1<<EG_SH)  * (clock/64.0) / ym2151->sampfreq;
	ym2151->eg_timer_overflow = 3 * (1<<EG_SH);

	YM2151Reset();
}


void YM2151Reset(void)
{
	int i;

	/* initialize hardware registers */
	for (i = 0; i < 32; i++)
	{
		memset(&ym2151->oper[i], 0, sizeof(FM_OPM));
		ym2151->oper[i].volume = MAX_ATT_INDEX;
		ym2151->oper[i].kc_i = 768; /* min kc_i value */
	}

	ym2151->eg_timer = 0;
	ym2151->eg_cnt   = 0;

	ym2151->lfo_timer  = 0;
	ym2151->lfo_counter= 0;
	ym2151->lfo_phase  = 0;
	ym2151->lfo_wsel   = 0;
	ym2151->pmd = 0;
	ym2151->amd = 0;
	ym2151->lfa = 0;
	ym2151->lfp = 0;

	ym2151->test= 0;

	ym2151->irq_enable = 0;
	timer_enable(YM2151_TIMERA, 0);
	timer_enable(YM2151_TIMERB, 0);
	ym2151->timer_A_index = 0;
	ym2151->timer_B_index = 0;
	ym2151->timer_A_index_old = 0;
	ym2151->timer_B_index_old = 0;

	ym2151->noise     = 0;
	ym2151->noise_rng = 0;
	ym2151->noise_p   = 0;
	ym2151->noise_f   = ym2151->noise_tab[0];

	ym2151->csm_req	= 0;
	ym2151->status    = 0;

	YM2151WriteReg(0x1b, 0);	/* only because of CT1, CT2 output pins */
	YM2151WriteReg(0x18, 0);	/* set LFO frequency */
	for (i = 0x20; i < 0x100; i++)	/* set the operators */
	{
		YM2151WriteReg(i, 0);
	}
}


/******************************************************************************
	セーブ/ロード ステート
******************************************************************************/

#ifdef SAVE_STATE

STATE_SAVE( ym2151 )
{
	int i;

	for (i = 0; i < 32; i++)
	{
		FM_OPM *op;

		op = &ym2151->oper[(i & 7) * 4 + (i >> 3)];

		state_save_long(&op->phase, 1);
		state_save_long(&op->freq, 1);
		state_save_long(&op->dt1, 1);
		state_save_long(&op->mul, 1);
		state_save_long(&op->dt1_i, 1);
		state_save_long(&op->dt2, 1);
		state_save_long(&op->mem_value, 1);

		state_save_long(&op->fb_shift, 1);
		state_save_long(&op->fb_out_curr, 1);
		state_save_long(&op->fb_out_prev, 1);
		state_save_long(&op->kc, 1);
		state_save_long(&op->kc_i, 1);
		state_save_long(&op->pms, 1);
		state_save_long(&op->ams, 1);

		state_save_long(&op->AMmask, 1);
		state_save_long(&op->state, 1);
		state_save_byte(&op->eg_sh_ar, 1);
		state_save_byte(&op->eg_sel_ar, 1);
		state_save_long(&op->tl, 1);
		state_save_long(&op->volume, 1);
		state_save_byte(&op->eg_sh_d1r, 1);
		state_save_byte(&op->eg_sel_d1r, 1);
		state_save_long(&op->d1l, 1);
		state_save_byte(&op->eg_sh_d2r, 1);
		state_save_byte(&op->eg_sel_d2r, 1);
		state_save_byte(&op->eg_sh_rr, 1);
		state_save_byte(&op->eg_sel_rr, 1);

		state_save_long(&op->key, 1);
		state_save_long(&op->ks, 1);
		state_save_long(&op->ar, 1);
		state_save_long(&op->d1r, 1);
		state_save_long(&op->d2r, 1);
		state_save_long(&op->rr, 1);
	}

	state_save_long(ym2151->pan, 8);

	state_save_long(&ym2151->eg_cnt, 1);
	state_save_long(&ym2151->eg_timer, 1);
	state_save_long(&ym2151->eg_timer_add, 1);
	state_save_long(&ym2151->eg_timer_overflow, 1);

	state_save_long(&ym2151->lfo_phase, 1);
	state_save_long(&ym2151->lfo_timer, 1);
	state_save_long(&ym2151->lfo_timer_add, 1);
	state_save_long(&ym2151->lfo_overflow, 1);
	state_save_long(&ym2151->lfo_counter, 1);
	state_save_long(&ym2151->lfo_counter_add, 1);
	state_save_byte(&ym2151->lfo_wsel, 1);
	state_save_byte(&ym2151->amd, 1);
	state_save_byte(&ym2151->pmd, 1);
	state_save_long(&ym2151->lfa, 1);
	state_save_long(&ym2151->lfp, 1);

	state_save_byte(&ym2151->test, 1);
	state_save_byte(&ym2151->ct, 1);

	state_save_long(&ym2151->noise, 1);
	state_save_long(&ym2151->noise_rng, 1);
	state_save_long(&ym2151->noise_p, 1);
	state_save_long(&ym2151->noise_f, 1);

	state_save_long(&ym2151->csm_req, 1);
	state_save_long(&ym2151->irq_enable, 1);
	state_save_long(&ym2151->status, 1);

	state_save_long(&ym2151->timer_A_index, 1);
	state_save_long(&ym2151->timer_B_index, 1);
	state_save_long(&ym2151->timer_A_index_old, 1);
	state_save_long(&ym2151->timer_B_index_old, 1);

	state_save_byte(ym2151->connect, 8);

	state_save_long(&option_samplerate, 1);

	state_save_okim6295(fp);
}

STATE_LOAD( ym2151 )
{
	int i;

	for (i = 0; i < 32; i++)
	{
		FM_OPM *op;

		op = &ym2151->oper[(i & 7) * 4 + (i >> 3)];

		state_load_long(&op->phase, 1);
		state_load_long(&op->freq, 1);
		state_load_long(&op->dt1, 1);
		state_load_long(&op->mul, 1);
		state_load_long(&op->dt1_i, 1);
		state_load_long(&op->dt2, 1);
		state_load_long(&op->mem_value, 1);

		state_load_long(&op->fb_shift, 1);
		state_load_long(&op->fb_out_curr, 1);
		state_load_long(&op->fb_out_prev, 1);
		state_load_long(&op->kc, 1);
		state_load_long(&op->kc_i, 1);
		state_load_long(&op->pms, 1);
		state_load_long(&op->ams, 1);

		state_load_long(&op->AMmask, 1);
		state_load_long(&op->state, 1);
		state_load_byte(&op->eg_sh_ar, 1);
		state_load_byte(&op->eg_sel_ar, 1);
		state_load_long(&op->tl, 1);
		state_load_long(&op->volume, 1);
		state_load_byte(&op->eg_sh_d1r, 1);
		state_load_byte(&op->eg_sel_d1r, 1);
		state_load_long(&op->d1l, 1);
		state_load_byte(&op->eg_sh_d2r, 1);
		state_load_byte(&op->eg_sel_d2r, 1);
		state_load_byte(&op->eg_sh_rr, 1);
		state_load_byte(&op->eg_sel_rr, 1);

		state_load_long(&op->key, 1);
		state_load_long(&op->ks, 1);
		state_load_long(&op->ar, 1);
		state_load_long(&op->d1r, 1);
		state_load_long(&op->d2r, 1);
		state_load_long(&op->rr, 1);
	}

	state_load_long(ym2151->pan, 8);

	state_load_long(&ym2151->eg_cnt, 1);
	state_load_long(&ym2151->eg_timer, 1);
	state_load_long(&ym2151->eg_timer_add, 1);
	state_load_long(&ym2151->eg_timer_overflow, 1);

	state_load_long(&ym2151->lfo_phase, 1);
	state_load_long(&ym2151->lfo_timer, 1);
	state_load_long(&ym2151->lfo_timer_add, 1);
	state_load_long(&ym2151->lfo_overflow, 1);
	state_load_long(&ym2151->lfo_counter, 1);
	state_load_long(&ym2151->lfo_counter_add, 1);
	state_load_byte(&ym2151->lfo_wsel, 1);
	state_load_byte(&ym2151->amd, 1);
	state_load_byte(&ym2151->pmd, 1);
	state_load_long(&ym2151->lfa, 1);
	state_load_long(&ym2151->lfp, 1);

	state_load_byte(&ym2151->test, 1);
	state_load_byte(&ym2151->ct, 1);

	state_load_long(&ym2151->noise, 1);
	state_load_long(&ym2151->noise_rng, 1);
	state_load_long(&ym2151->noise_p, 1);
	state_load_long(&ym2151->noise_f, 1);

	state_load_long(&ym2151->csm_req, 1);
	state_load_long(&ym2151->irq_enable, 1);
	state_load_long(&ym2151->status, 1);

	state_load_long(&ym2151->timer_A_index, 1);
	state_load_long(&ym2151->timer_B_index, 1);
	state_load_long(&ym2151->timer_A_index_old, 1);
	state_load_long(&ym2151->timer_B_index_old, 1);

	state_load_byte(ym2151->connect, 8);

	state_load_long(&option_samplerate, 1);

	state_load_okim6295(fp);
}

#endif /* SAVE_STATE */
