ym2151.c

十七种模拟器源代码 非常有用的作课程设计不可缺少的

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "driver.h"
#include "sasound.h"
#include "ym2151.h"


/*undef this to not use MAME timer system*/
//#define USE_MAME_TIMERS

/*#define FM_EMU*/
#ifdef FM_EMU
	#define INLINE static __inline__
	#ifdef USE_MAME_TIMERS
		#undef USE_MAME_TIMERS
	#endif
#endif
#ifdef USE_MAME_TIMERS
	/*#define LOG_CYM_FILE*/
	#ifdef LOG_CYM_FILE
		FILE * cymfile = NULL;
		void * cymfiletimer = 0;
	#endif
#endif


/*operator data*/
typedef struct{
	unsigned int phase;		/*accumulated operator phase*/
	unsigned int freq;		/*operator frequency*/
	signed   int DT1v;		/*operator DT1 phase inc/decrement*/

	unsigned int MUL;		/*phase multiply*/
	unsigned int DT1;		/*DT1 * 32      */
	unsigned int DT2;		/*DT2 index     */

	signed   int *connect;	/*operator output 'direction'*/

/*Begin of channel specific data*/
/*note: each operator number 0 contains channel specific data*/
	unsigned int FeedBack;	/*feedback shift value for operators 0 in each channel*/
	signed   int FB;		/*operator self feedback value used only by operators 0*/
	signed   int FB0;		/*previous output value*/
	unsigned int KC;		/*operator KC (copied to all operators)*/
	unsigned int KCindex;	/*speedup*/
	unsigned int PMS;		/*channel PMS*/
	unsigned int AMS;		/*channel AMS*/
/*End of channel specific data*/

	unsigned int AMSmask;	/*LFO AMS enable mask*/

	unsigned int state;		/*Envelope state: 4-attack(AR) 3-decay(D1R) 2-sustain(D2R) 1-release(RR) 0-off*/
	unsigned int delta_AR;	/*volume delta for attack phase*/
	unsigned int TL;		/*Total attenuation Level*/
	signed   int volume;	/*operator attenuation level*/
	unsigned int delta_D1R;	/*volume delta for decay phase*/
	unsigned int D1L;		/*EG switches to D2R, when envelope reaches this level*/
	unsigned int delta_D2R;	/*volume delta for sustain phase*/
	unsigned int delta_RR;	/*volume delta for release phase*/

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

	unsigned int KS;		/*Key Scale     */
	unsigned int AR;		/*Attack rate   */
	unsigned int D1R;		/*Decay rate    */
	unsigned int D2R;		/*Sustain rate  */
	unsigned int RR;		/*Release rate  */

	unsigned int reserved0;	/**/
	signed   int reserved1;	/**/
	signed   int reserved2;	/**/

} OscilRec;


typedef struct
{
	OscilRec Oscils[32];	/*there are 32 operators in YM2151*/

	unsigned int PAN[16];	/*channels output masks (0xffffffff = enable)*/

	unsigned int LFOphase;	/*accumulated LFO phase         */
	unsigned int LFOfrq;	/*LFO frequency                 */
	unsigned int LFOwave;	/*LFO waveform (0-saw, 1-square, 2-triangle, 3-random noise)*/
	unsigned int PMD;		/*LFO Phase Modulation Depth    */
	unsigned int AMD;		/*LFO Amplitude Modulation Depth*/
	unsigned int LFA;		/*current AM from LFO*/
	signed   int LFP;		/*current PM from LFO*/

	unsigned int test;		/*TEST register*/

	unsigned int CT;		/*output control pins (bit7 CT2, bit6 CT1)*/

	unsigned int noise;		/*noise register (bit 7 - noise enable, bits 4-0 - noise period*/
	unsigned int noiseRNG;	/*17 bit noise shift register*/
	unsigned int noise_p;	/*noise 'phase'*/
	unsigned int noise_f;	/*noise period*/

	unsigned int CSMreq;	/*CSM KEYON/KEYOFF sequence request*/

	unsigned int IRQenable;	/*IRQ enable for timer B (bit 3) and timer A (bit 2); bit 7 - CSM mode (keyon to all slots, everytime timer A overflows)*/
	unsigned int status;	/*chip status (BUSY, IRQ Flags)*/

#ifdef USE_MAME_TIMERS
	void *TimATimer,*TimBTimer;	/*ASG 980324 -- added for tracking timers*/
	double TimerATime[1024];	/*Timer A times for MAME*/
	double TimerBTime[256];		/*Timer B times for MAME*/
#else
	int TimA,TimB;				/*timer A,B enable (0-disabled)*/
	signed int TimAVal,TimBVal;	/*current value of timer*/
	unsigned int TimerA[1024];	/*Timer A deltas*/
	unsigned int TimerB[256];	/*Timer B deltas*/
#endif
	unsigned int TimAIndex;		/*Timer A index*/
	unsigned int TimBIndex;		/*Timer B index*/

	unsigned int TimAOldIndex;	/*Timer A previous index*/
	unsigned int TimBOldIndex;	/*Timer B previous index*/

	/*
	*   Frequency-deltas to get the closest frequency possible.
	*   There're 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
	*/
	unsigned int 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.
	*/
	signed   int DT1freq[8*32];		/*8 DT1 levels, 32 KC values*/
	unsigned int EG_tab [32+64+32];	/*Envelope Generator deltas (32 + 64 rates + 32 RKS)*/
	unsigned int LFOfreq[256];		/*LFO frequency deltas*/
	unsigned int noise_tab[32];		/*17bit Noise Generator periods*/

	void (*irqhandler)(int irq);	/*IRQ function handler*/
	mem_write_handler porthandler;	/*port write function handler*/

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

} YM2151;


/*
**  Shifts below are subject to change when sampling frequency changes...
*/
#define FREQ_SH			16  /* 16.16 fixed point (frequency calculations) */
#define ENV_SH			16  /* 16.16 fixed point (envelope calculations)  */
#define LFO_SH			23  /*  9.23 fixed point (LFO calculations)       */
#define TIMER_SH		16  /* 16.16 fixed point (timers calculations)    */

#define FREQ_MASK		((1<<FREQ_SH)-1)
#define ENV_MASK		((1<<ENV_SH)-1)

#define ENV_BITS		10
#define ENV_LEN			(1<<ENV_BITS)
#define ENV_STEP		(128.0/ENV_LEN)
#define ENV_QUIET		((int)(0x68/(ENV_STEP)))

#define MAX_ATT_INDEX	((ENV_LEN<<ENV_SH)-1) /*1023.ffff*/
#define MIN_ATT_INDEX	(      (1<<ENV_SH)-1) /*   0.ffff*/

#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 LFO_BITS		9
#define LFO_LEN			(1<<LFO_BITS)
#define LFO_MASK		(LFO_LEN-1)


#if (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)
 * ENV_LEN - sinus resolution (X axis)
*/
#define TL_TAB_LEN (13*2*TL_RES_LEN)
static signed int TL_TAB[TL_TAB_LEN];

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

/* four AM/PM LFO waveforms (8 in total)*/
static unsigned int lfo_tab[LFO_LEN*4*2];

/* LFO amplitude modulation depth table (128 levels)*/
static unsigned int lfo_md_tab[128];

/* translate from D1L to volume index (16 D1L levels)*/
static unsigned int D1L_tab[16];

/*
 *   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 unsigned int DT2_tab[4] = { 0, 384, 500, 608 };

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

static unsigned char 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 unsigned short 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
};




static YM2151 * YMPSG = NULL;	/* array of YM2151's */
static unsigned int YMNumChips;	/* total # of YM2151's emulated */


/*these variables stay here because of speedup purposes only */
static YM2151 * PSG;
static signed int chanout[8];
static signed int c1,m2,c2; /*Phase Modulation input for operators 2,3,4*/



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

#if defined SAVE_SAMPLE || defined SAVE_SEPARATE_CHANNELS
static FILE *sample[9];
#endif



/* own PI definition */
#ifdef PI
	#undef PI
#endif
#define PI 3.14159265358979323846

static void 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 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 ];
		}
	#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("TL_TAB_LEN = %i (%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) * PI / SIN_LEN ); /* checked against the real chip */

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

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

		o = o / (ENV_STEP/4);

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

		sin_tab[ i ] = n*2 + (m>=0.0? 0: 1 );
		/*logerror("sin [%4i]= %4i (TL_TAB value=%5i)\n", i, sin_tab[i],TL_TAB[sin_tab[i]]);*/
	}

	/*logerror("ENV_QUIET= %08x\n",ENV_QUIET );*/


	/* calculate LFO AM waveforms*/
	for (x=0; x<4; x++)
	{
	    for (i=0; i<LFO_LEN; i++)
	    {
		switch (x)
		{
		case 0:	/* saw (255 down to 0) */
			m = 255 - (i/2);
			break;
		case 1: /* square (255,0) */
			if (i<256)
				m = 255;
			else
				m = 0;
			break;
		case 2: /* triangle (255 down to 0, up to 255) */
			if (i<256)
				m = 255 - i;
			else
				m = i - 256;
			break;
		case 3: /* random (range 0 to 255) */
			m = ((int)rand()) & 255;
			break;
		}
		/* we reach m = zero here !!!*/

		if (m>0.0)
			o = 8*log(255.0/m)/log(2);  /* convert to 'decibels' */
		else
		{
			if (m<0.0)
				o = 8*log(-255.0/m)/log(2); /* convert to 'decibels' */
			else
				o = 8*log(255.0/0.01)/log(2); /* small number */
		}

		o = o / (ENV_STEP/4);

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

		lfo_tab[ x*LFO_LEN*2 + i*2 ] = n*2 + (m>=0.0? 0: 1 );
		/*logerror("lfo am waveofs[%i] %04i = %i\n", x, i*2, lfo_tab[ x*LFO_LEN*2 + i*2 ] );*/
	    }
	}
	for (i=0; i<128; i++)
	{
		m = i*2; /*m=0,2,4,6,8,10,..,252,254*/

		/* we reach m = zero here !!!*/

		if (m>0.0)
			o = 8*log(8192.0/m)/log(2);  /* convert to 'decibels' */
		else
			o = 8*log(8192.0/0.01)/log(2); /* small number (m=0)*/

		o = o / (ENV_STEP/4);

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

		lfo_md_tab[ i ] = n*2;
		/*logerror("lfo_md_tab[%i](%i) = ofs %i shr by %i\n", i, i*2, (lfo_md_tab[i]>>1)&255, lfo_md_tab[i]>>9 );*/
	}

	/* calculate LFO PM waveforms*/
	for (x=0; x<4; x++)
	{
	    for (i=0; i<LFO_LEN; i++)
	    {
		switch (x)
		{
		case 0:	/* saw (0 to 127, -128 to -1) */
			if (i<256)
				m = (i/2);
			else
				m = (i/2)-256;
			break;
		case 1: /* square (127,-128) */
			if (i<256)
				m = 127;
			else
				m = -128;
			break;
		case 2: /* triangle (0 to 127,127 to -128,-127 to 0) */
			if (i<128)
				m = i; /*0 to 127*/
			else
			{
				if (i<384)
					m = 255 - i; /*127 down to -128*/
				else
					m = i - 511; /*-127 to 0*/
			}
			break;
		case 3: /* random (range -128 to 127) */
			m = ((int)rand()) & 255;
			m -=128;
			break;
		}
		/* we reach m = zero here !!!*/

		if (m>0.0)