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◆ main openmsx / src / sound / YM2413Okazaki.cc
48.1 KiB · C++ · last changed chore(): initial commit 1 month ago source blame history raw
e8555c89 Andy McCall 1 
/*
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 * Based on:
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 *    emu2413.c -- YM2413 emulator written by Mitsutaka Okazaki 2001
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 * heavily rewritten to fit openMSX structure
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 */
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#include "YM2413Okazaki.hh"
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#include "Math.hh"
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#include "cstd.hh"
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#include "enumerate.hh"
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#include "inline.hh"
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#include "narrow.hh"
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#include "one_of.hh"
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#include "ranges.hh"
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#include "serialize.hh"
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#include "unreachable.hh"
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#include "xrange.hh"
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#include <algorithm>
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#include <array>
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#include <cassert>
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#include <iostream>
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namespace openmsx {
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namespace YM2413Okazaki {
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// Number of bits in 'PhaseModulation' fixed point type.
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static constexpr int PM_FP_BITS =  8;
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// Dynamic range (Accuracy of sin table)
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static constexpr int DB_BITS = 8;
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static constexpr int DB_MUTE = 1 << DB_BITS;
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static constexpr int DBTABLEN = 4 * DB_MUTE; // enough to not have to check for overflow
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static constexpr double DB_STEP = 48.0 / DB_MUTE;
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static constexpr double EG_STEP = 0.375;
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static constexpr double TL_STEP = 0.75;
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// Phase increment counter
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static constexpr int DP_BITS = 18;
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static constexpr int DP_BASE_BITS = DP_BITS - PG_BITS;
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// Dynamic range of envelope
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static constexpr int EG_BITS = 7;
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// Bits for linear value
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static constexpr int DB2LIN_AMP_BITS = 8;
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static constexpr int SLOT_AMP_BITS = DB2LIN_AMP_BITS;
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// Bits for Amp modulator
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static constexpr int AM_PG_BITS = 8;
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static constexpr int AM_PG_WIDTH = 1 << AM_PG_BITS;
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static constexpr int AM_DP_BITS = 16;
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static constexpr int AM_DP_WIDTH = 1 << AM_DP_BITS;
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static constexpr int AM_DP_MASK = AM_DP_WIDTH - 1;
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// LFO Amplitude Modulation table (verified on real YM3812)
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// 27 output levels (triangle waveform);
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// 1 level takes one of: 192, 256 or 448 samples
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//
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// Length: 210 elements.
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//  Each of the elements has to be repeated
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//  exactly 64 times (on 64 consecutive samples).
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//  The whole table takes: 64 * 210 = 13440 samples.
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//
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// Verified on real YM3812 (OPL2), but I believe it's the same for YM2413
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// because it closely matches the YM2413 AM parameters:
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//    speed = 3.7Hz
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//    depth = 4.875dB
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// Also this approach can be easily implemented in HW, the previous one (see SVN
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// history) could not.
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static constexpr unsigned LFO_AM_TAB_ELEMENTS = 210;
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// Extra (derived) constants
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static constexpr EnvPhaseIndex EG_DP_MAX = EnvPhaseIndex(1 << 7);
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static constexpr EnvPhaseIndex EG_DP_INF = EnvPhaseIndex(1 << 8); // as long as it's bigger
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// LFO Phase Modulation table (copied from Burczynski core)
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static constexpr std::array pmTable = {
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	std::array<int8_t, 8>{0, 0, 0, 0, 0, 0, 0, 0}, // FNUM = 000xxxxxx
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	std::array<int8_t, 8>{0, 0, 1, 0, 0, 0,-1, 0}, // FNUM = 001xxxxxx
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	std::array<int8_t, 8>{0, 1, 2, 1, 0,-1,-2,-1}, // FNUM = 010xxxxxx
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	std::array<int8_t, 8>{0, 1, 3, 1, 0,-1,-3,-1}, // FNUM = 011xxxxxx
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	std::array<int8_t, 8>{0, 2, 4, 2, 0,-2,-4,-2}, // FNUM = 100xxxxxx
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	std::array<int8_t, 8>{0, 2, 5, 2, 0,-2,-5,-2}, // FNUM = 101xxxxxx
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	std::array<int8_t, 8>{0, 3, 6, 3, 0,-3,-6,-3}, // FNUM = 110xxxxxx
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	std::array<int8_t, 8>{0, 3, 7, 3, 0,-3,-7,-3}, // FNUM = 111xxxxxx
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};
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// LFO Amplitude Modulation table (verified on real YM3812)
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static constexpr std::array<uint8_t, LFO_AM_TAB_ELEMENTS> lfo_am_table = {
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	0,0,0,0,0,0,0,
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	1,1,1,1,
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	2,2,2,2,
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	3,3,3,3,
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	4,4,4,4,
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	5,5,5,5,
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	6,6,6,6,
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	7,7,7,7,
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	8,8,8,8,
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	9,9,9,9,
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	10,10,10,10,
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	11,11,11,11,
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	12,12,12,12,
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	13,13,13,13,
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	14,14,14,14,
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	15,15,15,15,
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	16,16,16,16,
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	17,17,17,17,
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	18,18,18,18,
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	19,19,19,19,
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	20,20,20,20,
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	21,21,21,21,
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	22,22,22,22,
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	23,23,23,23,
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	24,24,24,24,
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	25,25,25,25,
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	26,26,26,
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	25,25,25,25,
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	24,24,24,24,
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	23,23,23,23,
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	22,22,22,22,
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	21,21,21,21,
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	20,20,20,20,
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	19,19,19,19,
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	18,18,18,18,
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	17,17,17,17,
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	16,16,16,16,
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	15,15,15,15,
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	14,14,14,14,
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	13,13,13,13,
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	12,12,12,12,
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	11,11,11,11,
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	10,10,10,10,
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	9,9,9,9,
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	8,8,8,8,
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	7,7,7,7,
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	6,6,6,6,
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	5,5,5,5,
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	4,4,4,4,
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	3,3,3,3,
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	2,2,2,2,
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	1,1,1,1,
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};
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// ML-table
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static constexpr std::array<uint8_t, 16> mlTable = {
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	1,   1*2,  2*2,  3*2,  4*2,  5*2,  6*2,  7*2,
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	8*2, 9*2, 10*2, 10*2, 12*2, 12*2, 15*2, 15*2
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};
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// dB to linear table (used by Slot)
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// dB(0 .. DB_MUTE-1) -> linear(0 .. DB2LIN_AMP_WIDTH)
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// indices in range:
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//   [0,        DB_MUTE )    actual values, from max to min
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//   [DB_MUTE,  DBTABLEN)    filled with min val (to allow some overflow in index)
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//   [DBTABLEN, 2*DBTABLEN)  as above but for negative output values
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static constexpr auto dB2LinTab = [] {
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	std::array<int, 2 * DBTABLEN> result = {};
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	for (int i : xrange(DB_MUTE - 1)) {
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		result[i] = int(double((1 << DB2LIN_AMP_BITS) - 1) *
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		                   cstd::pow<5, 3>(10, -double(i) * DB_STEP / 20));
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	}
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	result[DB_MUTE - 1] = 0;
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	for (auto i : xrange(DB_MUTE, DBTABLEN)) {
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		result[i] = 0;
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	}
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	for (auto i : xrange(DBTABLEN)) {
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		result[i + DBTABLEN] = -result[i];
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	}
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	return result;
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}();
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// Linear to Log curve conversion table (for Attack rate)
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static constexpr auto arAdjustTab = [] {
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	std::array<unsigned, 1 << EG_BITS> result = {};
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	result[0] = (1 << EG_BITS) - 1;
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	constexpr double l127 = cstd::log<5, 4>(127.0);
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	for (int i : xrange(1, 1 << EG_BITS)) {
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		result[i] = unsigned(double(1 << EG_BITS) - 1 -
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		         ((1 << EG_BITS) - 1) * cstd::log<5, 4>(double(i)) / l127);
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	}
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	return result;
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}();
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// KSL + TL Table   values are in range [0, 112]
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static constexpr auto tllTab = [] {
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	std::array<std::array<uint8_t, 16 * 8>, 4> result = {};
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	// Processed version of Table III-5 from the Application Manual.
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	constexpr std::array<int, 16> klTable = {
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		0, 24, 32, 37, 40, 43, 45, 47, 48, 50, 51, 52, 53, 54, 55, 56
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	};
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	// Note: KL [0..3] results in {0.0, 1.5, 3.0, 6.0} dB/oct.
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	// This is different from Y8950 and YMF262 which have {0, 3, 1.5, 6}.
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	// (2nd and 3rd elements are swapped). Verified on real YM2413.
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	for (auto freq : xrange(16 * 8)) {
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		int fnum  = freq % 16;
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		int block = freq / 16;
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		int tmp = 2 * klTable[fnum] - 16 * (7 - block);
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		for (auto KL : xrange(4)) {
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			unsigned t = (tmp <= 0 || KL == 0) ? 0 : (tmp >> (3 - KL));
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			assert(t <= 112);
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			result[KL][freq] = narrow<uint8_t>(t);
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		}
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	}
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	return result;
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}();
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// WaveTable for each envelope amp
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//  values are in range [0, DB_MUTE)             (for positive values)
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//                  or  [0, DB_MUTE) + DBTABLEN  (for negative values)
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static constexpr auto fullSinTable = [] {
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	auto lin2db = [](double d) {
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		// lin(+0.0 .. +1.0) to dB(DB_MUTE-1 .. 0)
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		return (d == 0)
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			? DB_MUTE - 1
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			: std::min(-int(20.0 * cstd::log10<5, 2>(d) / DB_STEP), DB_MUTE - 1); // 0 - 127
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	};
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	std::array<unsigned, PG_WIDTH> result = {};
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	for (auto i : xrange(PG_WIDTH / 4)) {
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		result[i] = lin2db(cstd::sin<2>(double(2.0 * Math::pi) * i / PG_WIDTH));
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	}
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	for (auto i : xrange(PG_WIDTH / 4)) {
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		result[PG_WIDTH / 2 - 1 - i] = result[i];
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	}
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	for (auto i : xrange(PG_WIDTH / 2)) {
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		result[PG_WIDTH / 2 + i] = DBTABLEN + result[i];
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	}
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	return result;
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}();
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static constexpr auto halfSinTable = [] {
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	std::array<unsigned, PG_WIDTH> result = {};
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	for (auto i : xrange(PG_WIDTH / 2)) {
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		result[i] = fullSinTable[i];
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	}
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	for (auto i : xrange(PG_WIDTH / 2, PG_WIDTH)) {
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		result[i] = fullSinTable[0];
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	}
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	return result;
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}();
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static constexpr std::array<std::span<const unsigned, PG_WIDTH>, 2> waveform = {
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	fullSinTable, halfSinTable
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};
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// Phase incr table for attack, decay and release
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//  note: original code had indices swapped. It also had
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//        a separate table for attack
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//  17.15 fixed point
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static constexpr auto dPhaseDrTab = [] {
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	std::array<std::array<int, 16>, 16> result = {};
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	for (auto Rks : xrange(16)) {
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		result[Rks][0] = 0;
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		for (auto DR : xrange(1, 16)) {
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			int RM = std::min(DR + (Rks >> 2), 15);
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			int RL = Rks & 3;
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			result[Rks][DR] =
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				((RL + 4) << EP_FP_BITS) >> (16 - RM);
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		}
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	}
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	return result;
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}();
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// Sustain level (17.15 fixed point)
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static constexpr auto slTab = [] {
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	std::array<unsigned, 16> result = {};
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	//for (auto [i, r] : enumerate(result)) { msvc bug
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	for (int i = 0; i < 16; ++i) {
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		double x = (i == 15) ? 48.0 : (3.0 * i);
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		result[i] = int(x / EG_STEP) << EP_FP_BITS;
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	}
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	return result;
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}();
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//
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// Helper functions
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//
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static constexpr unsigned EG2DB(unsigned d)
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{
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	return d * narrow_cast<unsigned>(EG_STEP / DB_STEP);
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}
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static constexpr unsigned TL2EG(unsigned d)
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{
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	assert(d < 64); // input is in range [0..63]
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	return d * narrow_cast<unsigned>(TL_STEP / EG_STEP);
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}
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static constexpr unsigned DB_POS(double x)
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{
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	auto result = int(x / DB_STEP);
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	assert(0 <= result);
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	assert(result < DB_MUTE);
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	return result;
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}
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static constexpr unsigned DB_NEG(double x)
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{
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	return DBTABLEN + DB_POS(x);
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}
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// Note: 'int' instead of 'bool' return value to silence clang-warning:
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//    warning: use of bitwise '&' with boolean operands [-Wbitwise-instead-of-logical]
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//    note: cast one or both operands to int to silence this warning
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static constexpr /*bool*/ int BIT(unsigned s, unsigned b)
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{
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	return narrow<int>((s >> b) & 1);
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}
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//
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// Patch
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//
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Patch::Patch()
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	: WF(waveform[0]), KL(tllTab[0])
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{
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	setKR(0);
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	setML(0);
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	setTL(0);
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	setFB(0);
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	setSL(0);
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}
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void Patch::initModulator(std::span<const uint8_t, 8> data)
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{
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	AMPM = (data[0] >> 6) &  3;
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	EG   = (data[0] >> 5) &  1;
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	setKR ((data[0] >> 4) &  1);
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	setML ((data[0] >> 0) & 15);
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	setKL ((data[2] >> 6) &  3);
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	setTL ((data[2] >> 0) & 63);
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	setWF ((data[3] >> 3) &  1);
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	setFB ((data[3] >> 0) &  7);
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	AR   = (data[4] >> 4) & 15;
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	DR   = (data[4] >> 0) & 15;
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	setSL ((data[6] >> 4) & 15);
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	RR   = (data[6] >> 0) & 15;
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}
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void Patch::initCarrier(std::span<const uint8_t, 8> data)
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{
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	AMPM = (data[1] >> 6) &  3;
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	EG   = (data[1] >> 5) &  1;
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	setKR ((data[1] >> 4) &  1);
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	setML ((data[1] >> 0) & 15);
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	setKL ((data[3] >> 6) &  3);
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	setTL (0);
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	setWF ((data[3] >> 4) &  1);
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	setFB (0);
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	AR   = (data[5] >> 4) & 15;
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	DR   = (data[5] >> 0) & 15;
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	setSL ((data[7] >> 4) & 15);
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	RR   = (data[7] >> 0) & 15;
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}
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void Patch::setKR(uint8_t value)
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{
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	KR = value ? 8 : 10;
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}
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void Patch::setML(uint8_t value)
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{
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	ML = mlTable[value];
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}
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void Patch::setKL(uint8_t value)
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{
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	KL = tllTab[value];
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}
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void Patch::setTL(uint8_t value)
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{
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	assert(value < 64);
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	TL = narrow<uint8_t>(TL2EG(value));
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}
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void Patch::setWF(uint8_t value)
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{
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	WF = waveform[value];
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}
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void Patch::setFB(uint8_t value)
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{
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	FB = value ? 8 - value : 0;
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}
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void Patch::setSL(uint8_t value)
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{
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	SL = slTab[value];
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}
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//
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// Slot
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//
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Slot::Slot()
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	: dPhaseDRTableRks(dPhaseDrTab[0])
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{
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}
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void Slot::reset()
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{
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	cPhase = 0;
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	std::ranges::fill(dPhase, 0);
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	output = 0;
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	feedback = 0;
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	setEnvelopeState(EnvelopeState::FINISH);
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	dPhaseDRTableRks = dPhaseDrTab[0];
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	tll = 0;
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	sustain = false;
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	volume = TL2EG(0);
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	slot_on_flag = 0;
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}
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void Slot::updatePG(unsigned freq)
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{
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	// Pre-calculate all phase-increments. The 8 different values are for
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	// the 8 steps of the PM stuff (for mod and car phase calculation).
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	// When PM isn't used then dPhase[0] is used (pmTable[.][0] == 0).
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	// The original Okazaki core calculated the PM stuff in a different
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	// way. This algorithm was copied from the Burczynski core because it
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	// is much more suited for a (cheap) hardware calculation.
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	unsigned fnum  = freq & 511;
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	unsigned block = freq / 512;
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	for (auto [pm, dP] : enumerate(dPhase)) {
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		unsigned tmp = ((2 * fnum + pmTable[fnum >> 6][pm]) * patch.ML) << block;
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		dP = tmp >> (21 - DP_BITS);
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	}
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}
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void Slot::updateTLL(unsigned freq, bool actAsCarrier)
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{
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	tll = patch.KL[freq >> 5] + (actAsCarrier ? volume : patch.TL);
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}
430
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void Slot::updateRKS(unsigned freq)
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{
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	unsigned rks = freq >> patch.KR;
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	assert(rks < 16);
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	dPhaseDRTableRks = dPhaseDrTab[rks];
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}
437
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void Slot::updateEG()
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{
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	switch (state) {
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	using enum EnvelopeState;
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	case ATTACK:
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		// Original code had separate table for AR, the values in
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		// this table were 12 times bigger than the values in the
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		// dPhaseDRTableRks table, expect for the value for AR=15.
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		// But when AR=15, the value doesn't matter.
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		//
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		// This factor 12 can also be seen in the attack/decay rates
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		// table in the ym2413 application manual (table III-7, page
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		// 13). For other chips like OPL1, OPL3 this ratio seems to be
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		// different.
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		eg_dPhase = EnvPhaseIndex::create(
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			dPhaseDRTableRks[patch.AR] * 12);
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		break;
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	case DECAY:
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		eg_dPhase = EnvPhaseIndex::create(dPhaseDRTableRks[patch.DR]);
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		break;
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	case SUSTAIN:
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		eg_dPhase = EnvPhaseIndex::create(dPhaseDRTableRks[patch.RR]);
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		break;
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	case RELEASE: {
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		unsigned idx = sustain ? 5
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		                       : (patch.EG ? patch.RR
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		                                   : 7);
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		eg_dPhase = EnvPhaseIndex::create(dPhaseDRTableRks[idx]);
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		break;
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	}
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	case SETTLE:
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		// Value based on ym2413 application manual:
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		//  - p10: (envelope graph)
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		//         DP: 10ms
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		//  - p13: (table III-7 attack and decay rates)
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		//         Rate 12-0 -> 10.22ms
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		//         Rate 12-1 ->  8.21ms
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		//         Rate 12-2 ->  6.84ms
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		//         Rate 12-3 ->  5.87ms
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		// The datasheet doesn't say anything about key-scaling for
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		// this state (in fact it doesn't say much at all about this
479 
		// state). Experiments showed that the with key-scaling the
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		// output matches closer the real HW. Also all other states use
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		// key-scaling.
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		eg_dPhase = EnvPhaseIndex::create(dPhaseDRTableRks[12]);
483 
		break;
484 
	case SUSHOLD:
485 
	case FINISH:
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		eg_dPhase = EnvPhaseIndex(0);
487 
		break;
488 
	}
489 
}
490
491 
void Slot::updateAll(unsigned freq, bool actAsCarrier)
492 
{
493 
	updatePG(freq);
494 
	updateTLL(freq, actAsCarrier);
495 
	updateRKS(freq);
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	updateEG(); // EG should be updated last
497 
}
498
499 
void Slot::setEnvelopeState(EnvelopeState state_)
500 
{
501 
	state = state_;
502 
	switch (state) {
503 
	using enum EnvelopeState;
504 
	case ATTACK:
505 
		eg_phase_max = (patch.AR == 15) ? EnvPhaseIndex(0) : EG_DP_MAX;
506 
		break;
507 
	case DECAY:
508 
		eg_phase_max = EnvPhaseIndex::create(narrow<int>(patch.SL));
509 
		break;
510 
	case SUSHOLD:
511 
		eg_phase_max = EG_DP_INF;
512 
		break;
513 
	case SETTLE:
514 
	case SUSTAIN:
515 
	case RELEASE:
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		eg_phase_max = EG_DP_MAX;
517 
		break;
518 
	case FINISH:
519 
		eg_phase = EG_DP_MAX;
520 
		eg_phase_max = EG_DP_INF;
521 
		break;
522 
	}
523 
	updateEG();
524 
}
525
526 
bool Slot::isActive() const
527 
{
528 
	return state != EnvelopeState::FINISH;
529 
}
530
531 
// Slot key on
532 
void Slot::slotOn()
533 
{
534 
	setEnvelopeState(EnvelopeState::ATTACK);
535 
	eg_phase = EnvPhaseIndex(0);
536 
	cPhase = 0;
537 
}
538
539 
// Slot key on, without resetting the phase
540 
void Slot::slotOn2()
541 
{
542 
	setEnvelopeState(EnvelopeState::ATTACK);
543 
	eg_phase = EnvPhaseIndex(0);
544 
}
545
546 
// Slot key off
547 
void Slot::slotOff()
548 
{
549 
	if (state == EnvelopeState::FINISH) return; // already in off state
550 
	if (state == EnvelopeState::ATTACK) {
551 
		eg_phase = EnvPhaseIndex(arAdjustTab[eg_phase.toInt()]);
552 
	}
553 
	setEnvelopeState(EnvelopeState::RELEASE);
554 
}
555
556
557 
// Change a rhythm voice
558 
void Slot::setPatch(const Patch& newPatch)
559 
{
560 
	patch = newPatch; // copy data
561 
	if ((state == EnvelopeState::SUSHOLD) && (patch.EG == 0)) {
562 
		setEnvelopeState(EnvelopeState::SUSTAIN);
563 
	}
564 
	setEnvelopeState(state); // recalculate eg_phase_max
565 
}
566
567 
// Set new volume based on 4-bit register value (0-15).
568 
void Slot::setVolume(unsigned value)
569 
{
570 
	// '<< 2' to transform 4 bits to the same range as the 6 bits TL field
571 
	volume = TL2EG(value << 2);
572 
}
573
574
575 
//
576 
// Channel
577 
//
578
579 
Channel::Channel()
580 
{
581 
	car.sibling = &mod;    // car needs a pointer to its sibling
582 
	mod.sibling = nullptr; // mod doesn't need this pointer
583 
}
584
585 
void Channel::reset(YM2413& ym2413)
586 
{
587 
	mod.reset();
588 
	car.reset();
589 
	setPatch(0, ym2413);
590 
}
591
592 
// Change a voice
593 
void Channel::setPatch(unsigned num, YM2413& ym2413)
594 
{
595 
	mod.setPatch(ym2413.getPatch(num, false));
596 
	car.setPatch(ym2413.getPatch(num, true));
597 
}
598
599 
// Set sustain parameter
600 
void Channel::setSustain(bool sustain, bool modActAsCarrier)
601 
{
602 
	car.sustain = sustain;
603 
	if (modActAsCarrier) {
604 
		mod.sustain = sustain;
605 
	}
606 
}
607
608 
// Channel key on
609 
void Channel::keyOn()
610 
{
611 
	// TODO Should we also test mod.slot_on_flag?
612 
	//      Should we    set    mod.slot_on_flag?
613 
	//      Can make a difference for channel 7/8 in rythm mode.
614 
	if (!car.slot_on_flag) {
615 
		car.setEnvelopeState(Slot::EnvelopeState::SETTLE);
616 
		// this will shortly set both car and mod to ATTACK state
617 
	}
618 
	car.slot_on_flag |= 1;
619 
	mod.slot_on_flag |= 1;
620 
}
621
622 
// Channel key off
623 
void Channel::keyOff()
624 
{
625 
	// Note: no mod.slotOff() in original code!!!
626 
	if (car.slot_on_flag) {
627 
		car.slot_on_flag &= ~1;
628 
		mod.slot_on_flag &= ~1;
629 
		if (!car.slot_on_flag) {
630 
			car.slotOff();
631 
		}
632 
	}
633 
}
634
635
636 
//
637 
// YM2413
638 
//
639
640 
static constexpr std::array inst_data = {
641 
	std::array<uint8_t, 8>{ 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 }, // user instrument
642 
	std::array<uint8_t, 8>{ 0x61,0x61,0x1e,0x17,0xf0,0x7f,0x00,0x17 }, // violin
643 
	std::array<uint8_t, 8>{ 0x13,0x41,0x16,0x0e,0xfd,0xf4,0x23,0x23 }, // guitar
644 
	std::array<uint8_t, 8>{ 0x03,0x01,0x9a,0x04,0xf3,0xf3,0x13,0xf3 }, // piano
645 
	std::array<uint8_t, 8>{ 0x11,0x61,0x0e,0x07,0xfa,0x64,0x70,0x17 }, // flute
646 
	std::array<uint8_t, 8>{ 0x22,0x21,0x1e,0x06,0xf0,0x76,0x00,0x28 }, // clarinet
647 
	std::array<uint8_t, 8>{ 0x21,0x22,0x16,0x05,0xf0,0x71,0x00,0x18 }, // oboe
648 
	std::array<uint8_t, 8>{ 0x21,0x61,0x1d,0x07,0x82,0x80,0x17,0x17 }, // trumpet
649 
	std::array<uint8_t, 8>{ 0x23,0x21,0x2d,0x16,0x90,0x90,0x00,0x07 }, // organ
650 
	std::array<uint8_t, 8>{ 0x21,0x21,0x1b,0x06,0x64,0x65,0x10,0x17 }, // horn
651 
	std::array<uint8_t, 8>{ 0x21,0x21,0x0b,0x1a,0x85,0xa0,0x70,0x07 }, // synthesizer
652 
	std::array<uint8_t, 8>{ 0x23,0x01,0x83,0x10,0xff,0xb4,0x10,0xf4 }, // harpsichord
653 
	std::array<uint8_t, 8>{ 0x97,0xc1,0x20,0x07,0xff,0xf4,0x22,0x22 }, // vibraphone
654 
	std::array<uint8_t, 8>{ 0x61,0x00,0x0c,0x05,0xc2,0xf6,0x40,0x44 }, // synthesizer bass
655 
	std::array<uint8_t, 8>{ 0x01,0x01,0x56,0x03,0x94,0xc2,0x03,0x12 }, // acoustic bass
656 
	std::array<uint8_t, 8>{ 0x21,0x01,0x89,0x03,0xf1,0xe4,0xf0,0x23 }, // electric guitar
657 
	std::array<uint8_t, 8>{ 0x07,0x21,0x14,0x00,0xee,0xf8,0xff,0xf8 },
658 
	std::array<uint8_t, 8>{ 0x01,0x31,0x00,0x00,0xf8,0xf7,0xf8,0xf7 },
659 
	std::array<uint8_t, 8>{ 0x25,0x11,0x00,0x00,0xf8,0xfa,0xf8,0x55 }
660 
};
661
662 
YM2413::YM2413()
663 
{
664 
	if (false) {
665 
		for (const auto& e : dB2LinTab) std::cout << e << ' ';
666 
		std::cout << '\n';
667
668 
		for (const auto& e : arAdjustTab) std::cout << e << ' ';
669 
		std::cout << '\n';
670
671 
		for (auto i : xrange(4)) {
672 
			for (auto j : xrange(16 * 8)) {
673 
				std::cout << int(tllTab[i][j]) << ' ';
674 
			}
675 
			std::cout << '\n';
676 
		}
677 
		std::cout << '\n';
678
679 
		for (const auto& e : fullSinTable) std::cout << e << ' ';
680 
		std::cout << '\n';
681 
		for (const auto& e : halfSinTable) std::cout << e << ' ';
682 
		std::cout << '\n';
683
684 
		for (auto i : xrange(16)) {
685 
			for (auto j : xrange(16)) {
686 
				std::cout << dPhaseDrTab[i][j] << ' ';
687 
			}
688 
			std::cout << '\n';
689 
		}
690 
		std::cout << '\n';
691
692 
		for (const auto& e : slTab) std::cout << e << ' ';
693 
		std::cout << '\n';
694 
	}
695
696 
	std::ranges::fill(reg, 0); // avoid UMR
697
698 
	for (auto i : xrange(16 + 3)) {
699 
		patches[i][0].initModulator(inst_data[i]);
700 
		patches[i][1].initCarrier  (inst_data[i]);
701 
	}
702
703 
	reset();
704 
}
705
706 
// Reset whole of OPLL except patch data
707 
void YM2413::reset()
708 
{
709 
	pm_phase = 0;
710 
	am_phase = 0;
711 
	noise_seed = 0xFFFF;
712
713 
	for (auto& ch : channels) {
714 
		ch.reset(*this);
715 
	}
716 
	for (auto i : xrange(uint8_t(0x40))) {
717 
		writeReg(i, 0);
718 
	}
719 
	registerLatch = 0;
720 
}
721
722 
// Drum key on
723 
void YM2413::keyOn_BD()
724 
{
725 
	Channel& ch6 = channels[6];
726 
	if (!ch6.car.slot_on_flag) {
727 
		ch6.car.setEnvelopeState(Slot::EnvelopeState::SETTLE);
728 
		// this will shortly set both car and mod to ATTACK state
729 
	}
730 
	ch6.car.slot_on_flag |= 2;
731 
	ch6.mod.slot_on_flag |= 2;
732 
}
733 
void YM2413::keyOn_HH()
734 
{
735 
	// TODO do these also use the SETTLE stuff?
736 
	Channel& ch7 = channels[7];
737 
	if (!ch7.mod.slot_on_flag) {
738 
		ch7.mod.slotOn2();
739 
	}
740 
	ch7.mod.slot_on_flag |= 2;
741 
}
742 
void YM2413::keyOn_SD()
743 
{
744 
	Channel& ch7 = channels[7];
745 
	if (!ch7.car.slot_on_flag) {
746 
		ch7.car.slotOn();
747 
	}
748 
	ch7.car.slot_on_flag |= 2;
749 
}
750 
void YM2413::keyOn_TOM()
751 
{
752 
	Channel& ch8 = channels[8];
753 
	if (!ch8.mod.slot_on_flag) {
754 
		ch8.mod.slotOn();
755 
	}
756 
	ch8.mod.slot_on_flag |= 2;
757 
}
758 
void YM2413::keyOn_CYM()
759 
{
760 
	Channel& ch8 = channels[8];
761 
	if (!ch8.car.slot_on_flag) {
762 
		ch8.car.slotOn2();
763 
	}
764 
	ch8.car.slot_on_flag |= 2;
765 
}
766
767 
// Drum key off
768 
void YM2413::keyOff_BD()
769 
{
770 
	Channel& ch6 = channels[6];
771 
	if (ch6.car.slot_on_flag) {
772 
		ch6.car.slot_on_flag &= ~2;
773 
		ch6.mod.slot_on_flag &= ~2;
774 
		if (!ch6.car.slot_on_flag) {
775 
			ch6.car.slotOff();
776 
		}
777 
	}
778 
}
779 
void YM2413::keyOff_HH()
780 
{
781 
	Channel& ch7 = channels[7];
782 
	if (ch7.mod.slot_on_flag) {
783 
		ch7.mod.slot_on_flag &= ~2;
784 
		if (!ch7.mod.slot_on_flag) {
785 
			ch7.mod.slotOff();
786 
		}
787 
	}
788 
}
789 
void YM2413::keyOff_SD()
790 
{
791 
	Channel& ch7 = channels[7];
792 
	if (ch7.car.slot_on_flag) {
793 
		ch7.car.slot_on_flag &= ~2;
794 
		if (!ch7.car.slot_on_flag) {
795 
			ch7.car.slotOff();
796 
		}
797 
	}
798 
}
799 
void YM2413::keyOff_TOM()
800 
{
801 
	Channel& ch8 = channels[8];
802 
	if (ch8.mod.slot_on_flag) {
803 
		ch8.mod.slot_on_flag &= ~2;
804 
		if (!ch8.mod.slot_on_flag) {
805 
			ch8.mod.slotOff();
806 
		}
807 
	}
808 
}
809 
void YM2413::keyOff_CYM()
810 
{
811 
	Channel& ch8 = channels[8];
812 
	if (ch8.car.slot_on_flag) {
813 
		ch8.car.slot_on_flag &= ~2;
814 
		if (!ch8.car.slot_on_flag) {
815 
			ch8.car.slotOff();
816 
		}
817 
	}
818 
}
819
820 
void YM2413::setRhythmFlags(uint8_t old)
821 
{
822 
	Channel& ch6 = channels[6];
823 
	Channel& ch7 = channels[7];
824 
	Channel& ch8 = channels[8];
825
826 
	// flags = X | X | mode | BD | SD | TOM | TC | HH
827 
	uint8_t flags = reg[0x0E];
828 
	if ((flags ^ old) & 0x20) {
829 
		if (flags & 0x20) {
830 
			// OFF -> ON
831 
			ch6.setPatch(16, *this);
832 
			ch7.setPatch(17, *this);
833 
			ch7.mod.setVolume(reg[0x37] >> 4);
834 
			ch8.setPatch(18, *this);
835 
			ch8.mod.setVolume(reg[0x38] >> 4);
836 
		} else {
837 
			// ON -> OFF
838 
			ch6.setPatch(reg[0x36] >> 4, *this);
839 
			keyOff_BD();
840 
			ch7.setPatch(reg[0x37] >> 4, *this);
841 
			keyOff_SD();
842 
			keyOff_HH();
843 
			ch8.setPatch(reg[0x38] >> 4, *this);
844 
			keyOff_TOM();
845 
			keyOff_CYM();
846 
		}
847 
	}
848 
	if (flags & 0x20) {
849 
		if (flags & 0x10) keyOn_BD();  else keyOff_BD();
850 
		if (flags & 0x08) keyOn_SD();  else keyOff_SD();
851 
		if (flags & 0x04) keyOn_TOM(); else keyOff_TOM();
852 
		if (flags & 0x02) keyOn_CYM(); else keyOff_CYM();
853 
		if (flags & 0x01) keyOn_HH();  else keyOff_HH();
854 
	}
855
856 
	unsigned freq6 = getFreq(6);
857 
	ch6.mod.updateAll(freq6, false);
858 
	ch6.car.updateAll(freq6, true);
859 
	unsigned freq7 = getFreq(7);
860 
	ch7.mod.updateAll(freq7, isRhythm());
861 
	ch7.car.updateAll(freq7, true);
862 
	unsigned freq8 = getFreq(8);
863 
	ch8.mod.updateAll(freq8, isRhythm());
864 
	ch8.car.updateAll(freq8, true);
865 
}
866
867 
void YM2413::update_key_status()
868 
{
869 
	for (auto [i, ch] : enumerate(channels)) {
870 
		uint8_t slot_on = (reg[0x20 + i] & 0x10) ? 1 : 0;
871 
		ch.mod.slot_on_flag = slot_on;
872 
		ch.car.slot_on_flag = slot_on;
873 
	}
874 
	if (isRhythm()) {
875 
		Channel& ch6 = channels[6];
876 
		ch6.mod.slot_on_flag |= uint8_t((reg[0x0e] & 0x10) ? 2 : 0); // BD1
877 
		ch6.car.slot_on_flag |= uint8_t((reg[0x0e] & 0x10) ? 2 : 0); // BD2
878 
		Channel& ch7 = channels[7];
879 
		ch7.mod.slot_on_flag |= uint8_t((reg[0x0e] & 0x01) ? 2 : 0); // HH
880 
		ch7.car.slot_on_flag |= uint8_t((reg[0x0e] & 0x08) ? 2 : 0); // SD
881 
		Channel& ch8 = channels[8];
882 
		ch8.mod.slot_on_flag |= uint8_t((reg[0x0e] & 0x04) ? 2 : 0); // TOM
883 
		ch8.car.slot_on_flag |= uint8_t((reg[0x0e] & 0x02) ? 2 : 0); // CYM
884 
	}
885 
}
886
887 
// Convert Amp(0 to EG_HEIGHT) to Phase(0 to 8PI)
888 
static constexpr int wave2_8pi(int e)
889 
{
890 
	int shift = SLOT_AMP_BITS - PG_BITS - 2;
891 
	if (shift > 0) {
892 
		return e >> shift;
893 
	} else {
894 
		return e << -shift;
895 
	}
896 
}
897
898 
// PG
899 
ALWAYS_INLINE unsigned Slot::calc_phase(unsigned lfo_pm)
900 
{
901 
	cPhase += dPhase[lfo_pm];
902 
	return cPhase >> DP_BASE_BITS;
903 
}
904
905 
// EG
906 
void Slot::calc_envelope_outline(unsigned& out)
907 
{
908 
	switch (state) {
909 
	using enum EnvelopeState;
910 
	case ATTACK:
911 
		out = 0;
912 
		eg_phase = EnvPhaseIndex(0);
913 
		setEnvelopeState(DECAY);
914 
		break;
915 
	case DECAY:
916 
		eg_phase = eg_phase_max;
917 
		setEnvelopeState(patch.EG ? SUSHOLD : SUSTAIN);
918 
		break;
919 
	case SUSTAIN:
920 
	case RELEASE:
921 
		setEnvelopeState(FINISH);
922 
		break;
923 
	case SETTLE:
924 
		// Comment copied from Burczynski code (didn't verify myself):
925 
		//   When CARRIER envelope gets down to zero level, phases in
926 
		//   BOTH operators are reset (at the same time?).
927 
		slotOn();
928 
		sibling->slotOn();
929 
		break;
930 
	case SUSHOLD:
931 
	case FINISH:
932 
	default:
933 
		UNREACHABLE;
934 
	}
935 
}
936 
template<bool HAS_AM, bool FIXED_ENV>
937 
ALWAYS_INLINE unsigned Slot::calc_envelope(int lfo_am, unsigned fixed_env)
938 
{
939 
	assert(!FIXED_ENV || (state == one_of(EnvelopeState::SUSHOLD, EnvelopeState::FINISH)));
940
941 
	if constexpr (FIXED_ENV) {
942 
		unsigned out = fixed_env;
943 
		if constexpr (HAS_AM) {
944 
			out += lfo_am; // [0, 768)
945 
			out |= 3;
946 
		} else {
947 
			// out |= 3   is already done in calc_fixed_env()
948 
		}
949 
		return out;
950 
	} else {
951 
		unsigned out = eg_phase.toInt(); // in range [0, 128]
952 
		if (state == EnvelopeState::ATTACK) {
953 
			out = arAdjustTab[out]; // [0, 128]
954 
		}
955 
		eg_phase += eg_dPhase;
956 
		if (eg_phase >= eg_phase_max) {
957 
			calc_envelope_outline(out);
958 
		}
959 
		out = EG2DB(out + tll); // [0, 732]
960 
		if constexpr (HAS_AM) {
961 
			out += lfo_am; // [0, 758]
962 
		}
963 
		return out | 3;
964 
	}
965 
}
966 
template<bool HAS_AM> unsigned Slot::calc_fixed_env() const
967 
{
968 
	assert(state == one_of(EnvelopeState::SUSHOLD, EnvelopeState::FINISH));
969 
	assert(eg_dPhase == EnvPhaseIndex(0));
970 
	unsigned out = eg_phase.toInt(); // in range [0, 128)
971 
	out = EG2DB(out + tll); // [0, 480)
972 
	if constexpr (!HAS_AM) {
973 
		out |= 3;
974 
	}
975 
	return out;
976 
}
977
978 
// CARRIER
979 
template<bool HAS_AM, bool FIXED_ENV>
980 
ALWAYS_INLINE int Slot::calc_slot_car(unsigned lfo_pm, int lfo_am, int fm, unsigned fixed_env)
981 
{
982 
	int phase = narrow<int>(calc_phase(lfo_pm)) + wave2_8pi(fm);
983 
	unsigned egOut = calc_envelope<HAS_AM, FIXED_ENV>(lfo_am, fixed_env);
984 
	int newOutput = dB2LinTab[patch.WF[phase & PG_MASK] + egOut];
985 
	output = (output + newOutput) >> 1;
986 
	return output;
987 
}
988
989 
// MODULATOR
990 
template<bool HAS_AM, bool HAS_FB, bool FIXED_ENV>
991 
ALWAYS_INLINE int Slot::calc_slot_mod(unsigned lfo_pm, int lfo_am, unsigned fixed_env)
992 
{
993 
	assert((patch.FB != 0) == HAS_FB);
994 
	unsigned phase = calc_phase(lfo_pm);
995 
	unsigned egOut = calc_envelope<HAS_AM, FIXED_ENV>(lfo_am, fixed_env);
996 
	if constexpr (HAS_FB) {
997 
		phase += wave2_8pi(feedback) >> patch.FB;
998 
	}
999 
	int newOutput = dB2LinTab[patch.WF[phase & PG_MASK] + egOut];
1000 
	feedback = (output + newOutput) >> 1;
1001 
	output = newOutput;
1002 
	return feedback;
1003 
}
1004
1005 
// TOM (ch8 mod)
1006 
ALWAYS_INLINE int Slot::calc_slot_tom()
1007 
{
1008 
	unsigned phase = calc_phase(0);
1009 
	unsigned egOut = calc_envelope<false, false>(0, 0);
1010 
	return dB2LinTab[patch.WF[phase & PG_MASK] + egOut];
1011 
}
1012
1013 
// SNARE (ch7 car)
1014 
ALWAYS_INLINE int Slot::calc_slot_snare(bool noise)
1015 
{
1016 
	unsigned phase = calc_phase(0);
1017 
	unsigned egOut = calc_envelope<false, false>(0, 0);
1018 
	return BIT(phase, 7)
1019 
		? dB2LinTab[(noise ? DB_POS(0.0) : DB_POS(15.0)) + egOut]
1020 
		: dB2LinTab[(noise ? DB_NEG(0.0) : DB_NEG(15.0)) + egOut];
1021 
}
1022
1023 
// TOP-CYM (ch8 car)
1024 
ALWAYS_INLINE int Slot::calc_slot_cym(unsigned phase7, unsigned phase8)
1025 
{
1026 
	unsigned egOut = calc_envelope<false, false>(0, 0);
1027 
	unsigned dbOut = (((BIT(phase7, PG_BITS - 8) ^
1028 
	                    BIT(phase7, PG_BITS - 1)) |
1029 
	                   BIT(phase7, PG_BITS - 7)) ^
1030 
	                  ( BIT(phase8, PG_BITS - 7) &
1031 
	                   !BIT(phase8, PG_BITS - 5)))
1032 
	               ? DB_NEG(3.0)
1033 
	               : DB_POS(3.0);
1034 
	return dB2LinTab[dbOut + egOut];
1035 
}
1036
1037 
// HI-HAT (ch7 mod)
1038 
ALWAYS_INLINE int Slot::calc_slot_hat(unsigned phase7, unsigned phase8, bool noise)
1039 
{
1040 
	unsigned egOut = calc_envelope<false, false>(0, 0);
1041 
	unsigned dbOut = (((BIT(phase7, PG_BITS - 8) ^
1042 
	                    BIT(phase7, PG_BITS - 1)) |
1043 
	                   BIT(phase7, PG_BITS - 7)) ^
1044 
	                  ( BIT(phase8, PG_BITS - 7) &
1045 
	                   !BIT(phase8, PG_BITS - 5)))
1046 
	               ? (noise ? DB_NEG(12.0) : DB_NEG(24.0))
1047 
	               : (noise ? DB_POS(12.0) : DB_POS(24.0));
1048 
	return dB2LinTab[dbOut + egOut];
1049 
}
1050
1051 
float YM2413::getAmplificationFactor() const
1052 
{
1053 
	return 1.0f / (1 << DB2LIN_AMP_BITS);
1054 
}
1055
1056 
bool YM2413::isRhythm() const
1057 
{
1058 
	return (reg[0x0E] & 0x20) != 0;
1059 
}
1060
1061 
unsigned YM2413::getFreq(unsigned channel) const
1062 
{
1063 
	// combined fnum (=9bit) and block (=3bit)
1064 
	assert(channel < 9);
1065 
	return reg[0x10 + channel] | ((reg[0x20 + channel] & 0x0F) << 8);
1066 
}
1067
1068 
Patch& YM2413::getPatch(unsigned instrument, bool carrier)
1069 
{
1070 
	return patches[instrument][carrier];
1071 
}
1072
1073 
template<unsigned FLAGS>
1074 
ALWAYS_INLINE void YM2413::calcChannel(Channel& ch, std::span<float> buf)
1075 
{
1076 
	// VC++ requires explicit conversion to bool. Compiler bug??
1077 
	const bool HAS_CAR_PM = (FLAGS &  1) != 0;
1078 
	const bool HAS_CAR_AM = (FLAGS &  2) != 0;
1079 
	const bool HAS_MOD_PM = (FLAGS &  4) != 0;
1080 
	const bool HAS_MOD_AM = (FLAGS &  8) != 0;
1081 
	const bool HAS_MOD_FB = (FLAGS & 16) != 0;
1082 
	const bool HAS_CAR_FIXED_ENV = (FLAGS & 32) != 0;
1083 
	const bool HAS_MOD_FIXED_ENV = (FLAGS & 64) != 0;
1084
1085 
	assert(((ch.car.patch.AMPM & 1) != 0) == HAS_CAR_PM);
1086 
	assert(((ch.car.patch.AMPM & 2) != 0) == HAS_CAR_AM);
1087 
	assert(((ch.mod.patch.AMPM & 1) != 0) == HAS_MOD_PM);
1088 
	assert(((ch.mod.patch.AMPM & 2) != 0) == HAS_MOD_AM);
1089
1090 
	unsigned tmp_pm_phase = pm_phase;
1091 
	unsigned tmp_am_phase = am_phase;
1092 
	unsigned car_fixed_env = 0; // dummy
1093 
	unsigned mod_fixed_env = 0; // dummy
1094 
	if constexpr (HAS_CAR_FIXED_ENV) {
1095 
		car_fixed_env = ch.car.calc_fixed_env<HAS_CAR_AM>();
1096 
	}
1097 
	if constexpr (HAS_MOD_FIXED_ENV) {
1098 
		mod_fixed_env = ch.mod.calc_fixed_env<HAS_MOD_AM>();
1099 
	}
1100
1101 
	for (auto& b : buf) {
1102 
		unsigned lfo_pm = 0;
1103 
		if constexpr (HAS_CAR_PM || HAS_MOD_PM) {
1104 
			// Copied from Burczynski:
1105 
			//  There are only 8 different steps for PM, and each
1106 
			//  step lasts for 1024 samples. This results in a PM
1107 
			//  freq of 6.1Hz (but datasheet says it's 6.4Hz).
1108 
			++tmp_pm_phase;
1109 
			lfo_pm = (tmp_pm_phase >> 10) & 7;
1110 
		}
1111 
		int lfo_am = 0; // avoid warning
1112 
		if constexpr (HAS_CAR_AM || HAS_MOD_AM) {
1113 
			++tmp_am_phase;
1114 
			if (tmp_am_phase == (LFO_AM_TAB_ELEMENTS * 64)) {
1115 
				tmp_am_phase = 0;
1116 
			}
1117 
			lfo_am = lfo_am_table[tmp_am_phase / 64];
1118 
		}
1119 
		int fm = ch.mod.calc_slot_mod<HAS_MOD_AM, HAS_MOD_FB, HAS_MOD_FIXED_ENV>(
1120 
		                      HAS_MOD_PM ? lfo_pm : 0, lfo_am, mod_fixed_env);
1121 
		b += narrow_cast<float>(ch.car.calc_slot_car<HAS_CAR_AM, HAS_CAR_FIXED_ENV>(
1122 
		                      HAS_CAR_PM ? lfo_pm : 0, lfo_am, fm, car_fixed_env));
1123 
	}
1124 
}
1125
1126 
void YM2413::generateChannels(std::span<float*, 9 + 5> bufs, unsigned num)
1127 
{
1128 
	assert(num != 0);
1129
1130 
	for (auto i : xrange(isRhythm() ? 6 : 9)) {
1131 
		Channel& ch = channels[i];
1132 
		if (ch.car.isActive()) {
1133 
			// Below we choose between 128 specialized versions of
1134 
			// calcChannel(). This allows to move a lot of
1135 
			// conditional code out of the inner-loop.
1136 
			using enum Slot::EnvelopeState;
1137 
			bool carFixedEnv = ch.car.state == one_of(SUSHOLD, FINISH);
1138 
			bool modFixedEnv = ch.mod.state == one_of(SUSHOLD, FINISH);
1139 
			if (ch.car.state == SETTLE) {
1140 
				modFixedEnv = false;
1141 
			}
1142 
			unsigned flags = ( ch.car.patch.AMPM     << 0) |
1143 
			                 ( ch.mod.patch.AMPM     << 2) |
1144 
			                 ((ch.mod.patch.FB != 0) << 4) |
1145 
			                 ( carFixedEnv           << 5) |
1146 
			                 ( modFixedEnv           << 6);
1147 
			switch (flags) {
1148 
			case   0: calcChannel<  0>(ch, {bufs[i], num}); break;
1149 
			case   1: calcChannel<  1>(ch, {bufs[i], num}); break;
1150 
			case   2: calcChannel<  2>(ch, {bufs[i], num}); break;
1151 
			case   3: calcChannel<  3>(ch, {bufs[i], num}); break;
1152 
			case   4: calcChannel<  4>(ch, {bufs[i], num}); break;
1153 
			case   5: calcChannel<  5>(ch, {bufs[i], num}); break;
1154 
			case   6: calcChannel<  6>(ch, {bufs[i], num}); break;
1155 
			case   7: calcChannel<  7>(ch, {bufs[i], num}); break;
1156 
			case   8: calcChannel<  8>(ch, {bufs[i], num}); break;
1157 
			case   9: calcChannel<  9>(ch, {bufs[i], num}); break;
1158 
			case  10: calcChannel< 10>(ch, {bufs[i], num}); break;
1159 
			case  11: calcChannel< 11>(ch, {bufs[i], num}); break;
1160 
			case  12: calcChannel< 12>(ch, {bufs[i], num}); break;
1161 
			case  13: calcChannel< 13>(ch, {bufs[i], num}); break;
1162 
			case  14: calcChannel< 14>(ch, {bufs[i], num}); break;
1163 
			case  15: calcChannel< 15>(ch, {bufs[i], num}); break;
1164 
			case  16: calcChannel< 16>(ch, {bufs[i], num}); break;
1165 
			case  17: calcChannel< 17>(ch, {bufs[i], num}); break;
1166 
			case  18: calcChannel< 18>(ch, {bufs[i], num}); break;
1167 
			case  19: calcChannel< 19>(ch, {bufs[i], num}); break;
1168 
			case  20: calcChannel< 20>(ch, {bufs[i], num}); break;
1169 
			case  21: calcChannel< 21>(ch, {bufs[i], num}); break;
1170 
			case  22: calcChannel< 22>(ch, {bufs[i], num}); break;
1171 
			case  23: calcChannel< 23>(ch, {bufs[i], num}); break;
1172 
			case  24: calcChannel< 24>(ch, {bufs[i], num}); break;
1173 
			case  25: calcChannel< 25>(ch, {bufs[i], num}); break;
1174 
			case  26: calcChannel< 26>(ch, {bufs[i], num}); break;
1175 
			case  27: calcChannel< 27>(ch, {bufs[i], num}); break;
1176 
			case  28: calcChannel< 28>(ch, {bufs[i], num}); break;
1177 
			case  29: calcChannel< 29>(ch, {bufs[i], num}); break;
1178 
			case  30: calcChannel< 30>(ch, {bufs[i], num}); break;
1179 
			case  31: calcChannel< 31>(ch, {bufs[i], num}); break;
1180 
			case  32: calcChannel< 32>(ch, {bufs[i], num}); break;
1181 
			case  33: calcChannel< 33>(ch, {bufs[i], num}); break;
1182 
			case  34: calcChannel< 34>(ch, {bufs[i], num}); break;
1183 
			case  35: calcChannel< 35>(ch, {bufs[i], num}); break;
1184 
			case  36: calcChannel< 36>(ch, {bufs[i], num}); break;
1185 
			case  37: calcChannel< 37>(ch, {bufs[i], num}); break;
1186 
			case  38: calcChannel< 38>(ch, {bufs[i], num}); break;
1187 
			case  39: calcChannel< 39>(ch, {bufs[i], num}); break;
1188 
			case  40: calcChannel< 40>(ch, {bufs[i], num}); break;
1189 
			case  41: calcChannel< 41>(ch, {bufs[i], num}); break;
1190 
			case  42: calcChannel< 42>(ch, {bufs[i], num}); break;
1191 
			case  43: calcChannel< 43>(ch, {bufs[i], num}); break;
1192 
			case  44: calcChannel< 44>(ch, {bufs[i], num}); break;
1193 
			case  45: calcChannel< 45>(ch, {bufs[i], num}); break;
1194 
			case  46: calcChannel< 46>(ch, {bufs[i], num}); break;
1195 
			case  47: calcChannel< 47>(ch, {bufs[i], num}); break;
1196 
			case  48: calcChannel< 48>(ch, {bufs[i], num}); break;
1197 
			case  49: calcChannel< 49>(ch, {bufs[i], num}); break;
1198 
			case  50: calcChannel< 50>(ch, {bufs[i], num}); break;
1199 
			case  51: calcChannel< 51>(ch, {bufs[i], num}); break;
1200 
			case  52: calcChannel< 52>(ch, {bufs[i], num}); break;
1201 
			case  53: calcChannel< 53>(ch, {bufs[i], num}); break;
1202 
			case  54: calcChannel< 54>(ch, {bufs[i], num}); break;
1203 
			case  55: calcChannel< 55>(ch, {bufs[i], num}); break;
1204 
			case  56: calcChannel< 56>(ch, {bufs[i], num}); break;
1205 
			case  57: calcChannel< 57>(ch, {bufs[i], num}); break;
1206 
			case  58: calcChannel< 58>(ch, {bufs[i], num}); break;
1207 
			case  59: calcChannel< 59>(ch, {bufs[i], num}); break;
1208 
			case  60: calcChannel< 60>(ch, {bufs[i], num}); break;
1209 
			case  61: calcChannel< 61>(ch, {bufs[i], num}); break;
1210 
			case  62: calcChannel< 62>(ch, {bufs[i], num}); break;
1211 
			case  63: calcChannel< 63>(ch, {bufs[i], num}); break;
1212 
			case  64: calcChannel< 64>(ch, {bufs[i], num}); break;
1213 
			case  65: calcChannel< 65>(ch, {bufs[i], num}); break;
1214 
			case  66: calcChannel< 66>(ch, {bufs[i], num}); break;
1215 
			case  67: calcChannel< 67>(ch, {bufs[i], num}); break;
1216 
			case  68: calcChannel< 68>(ch, {bufs[i], num}); break;
1217 
			case  69: calcChannel< 69>(ch, {bufs[i], num}); break;
1218 
			case  70: calcChannel< 70>(ch, {bufs[i], num}); break;
1219 
			case  71: calcChannel< 71>(ch, {bufs[i], num}); break;
1220 
			case  72: calcChannel< 72>(ch, {bufs[i], num}); break;
1221 
			case  73: calcChannel< 73>(ch, {bufs[i], num}); break;
1222 
			case  74: calcChannel< 74>(ch, {bufs[i], num}); break;
1223 
			case  75: calcChannel< 75>(ch, {bufs[i], num}); break;
1224 
			case  76: calcChannel< 76>(ch, {bufs[i], num}); break;
1225 
			case  77: calcChannel< 77>(ch, {bufs[i], num}); break;
1226 
			case  78: calcChannel< 78>(ch, {bufs[i], num}); break;
1227 
			case  79: calcChannel< 79>(ch, {bufs[i], num}); break;
1228 
			case  80: calcChannel< 80>(ch, {bufs[i], num}); break;
1229 
			case  81: calcChannel< 81>(ch, {bufs[i], num}); break;
1230 
			case  82: calcChannel< 82>(ch, {bufs[i], num}); break;
1231 
			case  83: calcChannel< 83>(ch, {bufs[i], num}); break;
1232 
			case  84: calcChannel< 84>(ch, {bufs[i], num}); break;
1233 
			case  85: calcChannel< 85>(ch, {bufs[i], num}); break;
1234 
			case  86: calcChannel< 86>(ch, {bufs[i], num}); break;
1235 
			case  87: calcChannel< 87>(ch, {bufs[i], num}); break;
1236 
			case  88: calcChannel< 88>(ch, {bufs[i], num}); break;
1237 
			case  89: calcChannel< 89>(ch, {bufs[i], num}); break;
1238 
			case  90: calcChannel< 90>(ch, {bufs[i], num}); break;
1239 
			case  91: calcChannel< 91>(ch, {bufs[i], num}); break;
1240 
			case  92: calcChannel< 92>(ch, {bufs[i], num}); break;
1241 
			case  93: calcChannel< 93>(ch, {bufs[i], num}); break;
1242 
			case  94: calcChannel< 94>(ch, {bufs[i], num}); break;
1243 
			case  95: calcChannel< 95>(ch, {bufs[i], num}); break;
1244 
			case  96: calcChannel< 96>(ch, {bufs[i], num}); break;
1245 
			case  97: calcChannel< 97>(ch, {bufs[i], num}); break;
1246 
			case  98: calcChannel< 98>(ch, {bufs[i], num}); break;
1247 
			case  99: calcChannel< 99>(ch, {bufs[i], num}); break;
1248 
			case 100: calcChannel<100>(ch, {bufs[i], num}); break;
1249 
			case 101: calcChannel<101>(ch, {bufs[i], num}); break;
1250 
			case 102: calcChannel<102>(ch, {bufs[i], num}); break;
1251 
			case 103: calcChannel<103>(ch, {bufs[i], num}); break;
1252 
			case 104: calcChannel<104>(ch, {bufs[i], num}); break;
1253 
			case 105: calcChannel<105>(ch, {bufs[i], num}); break;
1254 
			case 106: calcChannel<106>(ch, {bufs[i], num}); break;
1255 
			case 107: calcChannel<107>(ch, {bufs[i], num}); break;
1256 
			case 108: calcChannel<108>(ch, {bufs[i], num}); break;
1257 
			case 109: calcChannel<109>(ch, {bufs[i], num}); break;
1258 
			case 110: calcChannel<110>(ch, {bufs[i], num}); break;
1259 
			case 111: calcChannel<111>(ch, {bufs[i], num}); break;
1260 
			case 112: calcChannel<112>(ch, {bufs[i], num}); break;
1261 
			case 113: calcChannel<113>(ch, {bufs[i], num}); break;
1262 
			case 114: calcChannel<114>(ch, {bufs[i], num}); break;
1263 
			case 115: calcChannel<115>(ch, {bufs[i], num}); break;
1264 
			case 116: calcChannel<116>(ch, {bufs[i], num}); break;
1265 
			case 117: calcChannel<117>(ch, {bufs[i], num}); break;
1266 
			case 118: calcChannel<118>(ch, {bufs[i], num}); break;
1267 
			case 119: calcChannel<119>(ch, {bufs[i], num}); break;
1268 
			case 120: calcChannel<120>(ch, {bufs[i], num}); break;
1269 
			case 121: calcChannel<121>(ch, {bufs[i], num}); break;
1270 
			case 122: calcChannel<122>(ch, {bufs[i], num}); break;
1271 
			case 123: calcChannel<123>(ch, {bufs[i], num}); break;
1272 
			case 124: calcChannel<124>(ch, {bufs[i], num}); break;
1273 
			case 125: calcChannel<125>(ch, {bufs[i], num}); break;
1274 
			case 126: calcChannel<126>(ch, {bufs[i], num}); break;
1275 
			case 127: calcChannel<127>(ch, {bufs[i], num}); break;
1276 
			default: UNREACHABLE;
1277 
			}
1278 
		} else {
1279 
			bufs[i] = nullptr;
1280 
		}
1281 
	}
1282 
	// update AM, PM unit
1283 
	pm_phase += num;
1284 
	am_phase = (am_phase + num) % (LFO_AM_TAB_ELEMENTS * 64);
1285
1286 
	if (isRhythm()) {
1287 
		bufs[6] = nullptr;
1288 
		bufs[7] = nullptr;
1289 
		bufs[8] = nullptr;
1290
1291 
		Channel& ch6 = channels[6];
1292 
		Channel& ch7 = channels[7];
1293 
		Channel& ch8 = channels[8];
1294
1295 
		unsigned old_noise = noise_seed;
1296 
		unsigned old_cPhase7 = ch7.mod.cPhase;
1297 
		unsigned old_cPhase8 = ch8.car.cPhase;
1298
1299 
		if (ch6.car.isActive()) {
1300 
			for (auto sample : xrange(num)) {
1301 
				bufs[ 9][sample] += narrow_cast<float>(
1302 
				    2 * ch6.car.calc_slot_car<false, false>(
1303 
				        0, 0, ch6.mod.calc_slot_mod<
1304 
				                false, false, false>(0, 0, 0), 0));
1305 
			}
1306 
		} else {
1307 
			bufs[9] = nullptr;
1308 
		}
1309
1310 
		if (ch7.car.isActive()) {
1311 
			for (auto sample : xrange(num)) {
1312 
				noise_seed >>= 1;
1313 
				bool noise_bit = noise_seed & 1;
1314 
				if (noise_bit) noise_seed ^= 0x8003020;
1315 
				bufs[10][sample] += narrow_cast<float>(
1316 
					-2 * ch7.car.calc_slot_snare(noise_bit));
1317 
			}
1318 
		} else {
1319 
			bufs[10] = nullptr;
1320 
		}
1321
1322 
		if (ch8.car.isActive()) {
1323 
			for (auto sample : xrange(num)) {
1324 
				unsigned phase7 = ch7.mod.calc_phase(0);
1325 
				unsigned phase8 = ch8.car.calc_phase(0);
1326 
				bufs[11][sample] += narrow_cast<float>(
1327 
					-2 * ch8.car.calc_slot_cym(phase7, phase8));
1328 
			}
1329 
		} else {
1330 
			bufs[11] = nullptr;
1331 
		}
1332
1333 
		if (ch7.mod.isActive()) {
1334 
			// restore noise, ch7/8 cPhase
1335 
			noise_seed = old_noise;
1336 
			ch7.mod.cPhase = old_cPhase7;
1337 
			ch8.car.cPhase = old_cPhase8;
1338 
			for (auto sample : xrange(num)) {
1339 
				noise_seed >>= 1;
1340 
				bool noise_bit = noise_seed & 1;
1341 
				if (noise_bit) noise_seed ^= 0x8003020;
1342 
				unsigned phase7 = ch7.mod.calc_phase(0);
1343 
				unsigned phase8 = ch8.car.calc_phase(0);
1344 
				bufs[12][sample] += narrow_cast<float>(
1345 
					2 * ch7.mod.calc_slot_hat(phase7, phase8, noise_bit));
1346 
			}
1347 
		} else {
1348 
			bufs[12] = nullptr;
1349 
		}
1350
1351 
		if (ch8.mod.isActive()) {
1352 
			for (auto sample : xrange(num)) {
1353 
				bufs[13][sample] += narrow_cast<float>(
1354 
					2 * ch8.mod.calc_slot_tom());
1355 
			}
1356 
		} else {
1357 
			bufs[13] = nullptr;
1358 
		}
1359 
	} else {
1360 
		bufs[ 9] = nullptr;
1361 
		bufs[10] = nullptr;
1362 
		bufs[11] = nullptr;
1363 
		bufs[12] = nullptr;
1364 
		bufs[13] = nullptr;
1365 
	}
1366 
}
1367
1368 
void YM2413::writePort(bool port, uint8_t value, int /*offset*/)
1369 
{
1370 
	if (port == 0) {
1371 
		registerLatch = value;
1372 
	} else {
1373 
		writeReg(registerLatch & 0x3f, value);
1374 
	}
1375 
}
1376
1377 
void YM2413::pokeReg(uint8_t r, uint8_t data)
1378 
{
1379 
	writeReg(r, data);
1380 
}
1381
1382 
void YM2413::writeReg(uint8_t r, uint8_t data)
1383 
{
1384 
	assert(r < 0x40);
1385
1386 
	switch (r) {
1387 
	using enum Slot::EnvelopeState;
1388 
	case 0x00: {
1389 
		reg[r] = data;
1390 
		patches[0][0].AMPM = (data >> 6) & 3;
1391 
		patches[0][0].EG   = (data >> 5) & 1;
1392 
		patches[0][0].setKR ((data >> 4) & 1);
1393 
		patches[0][0].setML ((data >> 0) & 15);
1394 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1395 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1396 
				Channel& ch = channels[i];
1397 
				ch.setPatch(0, *this); // TODO optimize
1398 
				unsigned freq = getFreq(i);
1399 
				ch.mod.updatePG (freq);
1400 
				ch.mod.updateRKS(freq);
1401 
				ch.mod.updateEG();
1402 
			}
1403 
		}
1404 
		break;
1405 
	}
1406 
	case 0x01: {
1407 
		reg[r] = data;
1408 
		patches[0][1].AMPM = (data >> 6) & 3;
1409 
		patches[0][1].EG   = (data >> 5) & 1;
1410 
		patches[0][1].setKR ((data >> 4) & 1);
1411 
		patches[0][1].setML ((data >> 0) & 15);
1412 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1413 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1414 
				Channel& ch = channels[i];
1415 
				ch.setPatch(0, *this); // TODO optimize
1416 
				unsigned freq = getFreq(i);
1417 
				ch.car.updatePG (freq);
1418 
				ch.car.updateRKS(freq);
1419 
				ch.car.updateEG();
1420 
			}
1421 
		}
1422 
		break;
1423 
	}
1424 
	case 0x02: {
1425 
		reg[r] = data;
1426 
		patches[0][0].setKL((data >> 6) &  3);
1427 
		patches[0][0].setTL((data >> 0) & 63);
1428 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1429 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1430 
				Channel& ch = channels[i];
1431 
				ch.setPatch(0, *this); // TODO optimize
1432 
				bool actAsCarrier = (i >= 7) && isRhythm();
1433 
				assert(!actAsCarrier); (void)actAsCarrier;
1434 
				ch.mod.updateTLL(getFreq(i), false);
1435 
			}
1436 
		}
1437 
		break;
1438 
	}
1439 
	case 0x03: {
1440 
		reg[r] = data;
1441 
		patches[0][1].setKL((data >> 6) & 3);
1442 
		patches[0][1].setWF((data >> 4) & 1);
1443 
		patches[0][0].setWF((data >> 3) & 1);
1444 
		patches[0][0].setFB((data >> 0) & 7);
1445 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1446 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1447 
				Channel& ch = channels[i];
1448 
				ch.setPatch(0, *this); // TODO optimize
1449 
			}
1450 
		}
1451 
		break;
1452 
	}
1453 
	case 0x04: {
1454 
		reg[r] = data;
1455 
		patches[0][0].AR = (data >> 4) & 15;
1456 
		patches[0][0].DR = (data >> 0) & 15;
1457 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1458 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1459 
				Channel& ch = channels[i];
1460 
				ch.setPatch(0, *this); // TODO optimize
1461 
				ch.mod.updateEG();
1462 
				if (ch.mod.state == ATTACK) {
1463 
					ch.mod.setEnvelopeState(ATTACK);
1464 
				}
1465 
			}
1466 
		}
1467 
		break;
1468 
	}
1469 
	case 0x05: {
1470 
		reg[r] = data;
1471 
		patches[0][1].AR = (data >> 4) & 15;
1472 
		patches[0][1].DR = (data >> 0) & 15;
1473 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1474 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1475 
				Channel& ch = channels[i];
1476 
				ch.setPatch(0, *this); // TODO optimize
1477 
				ch.car.updateEG();
1478 
				if (ch.car.state == ATTACK) {
1479 
					ch.car.setEnvelopeState(ATTACK);
1480 
				}
1481 
			}
1482 
		}
1483 
		break;
1484 
	}
1485 
	case 0x06: {
1486 
		reg[r] = data;
1487 
		patches[0][0].setSL((data >> 4) & 15);
1488 
		patches[0][0].RR  = (data >> 0) & 15;
1489 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1490 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1491 
				Channel& ch = channels[i];
1492 
				ch.setPatch(0, *this); // TODO optimize
1493 
				ch.mod.updateEG();
1494 
				if (ch.mod.state == DECAY) {
1495 
					ch.mod.setEnvelopeState(DECAY);
1496 
				}
1497 
			}
1498 
		}
1499 
		break;
1500 
	}
1501 
	case 0x07: {
1502 
		reg[r] = data;
1503 
		patches[0][1].setSL((data >> 4) & 15);
1504 
		patches[0][1].RR  = (data >> 0) & 15;
1505 
		for (auto i : xrange(isRhythm() ? 6 : 9)) {
1506 
			if ((reg[0x30 + i] & 0xF0) == 0) {
1507 
				Channel& ch = channels[i];
1508 
				ch.setPatch(0, *this); // TODO optimize
1509 
				ch.car.updateEG();
1510 
				if (ch.car.state == DECAY) {
1511 
					ch.car.setEnvelopeState(DECAY);
1512 
				}
1513 
			}
1514 
		}
1515 
		break;
1516 
	}
1517 
	case 0x0E: {
1518 
		uint8_t old = reg[r];
1519 
		reg[r] = data;
1520 
		setRhythmFlags(old);
1521 
		break;
1522 
	}
1523 
	case 0x19: case 0x1A: case 0x1B: case 0x1C:
1524 
	case 0x1D: case 0x1E: case 0x1F:
1525 
		r -= 9; // verified on real YM2413
1526 
		[[fallthrough]];
1527 
	case 0x10: case 0x11: case 0x12: case 0x13: case 0x14:
1528 
	case 0x15: case 0x16: case 0x17: case 0x18: {
1529 
		reg[r] = data;
1530 
		unsigned cha = r & 0x0F; assert(cha < 9);
1531 
		Channel& ch = channels[cha];
1532 
		bool actAsCarrier = (cha >= 7) && isRhythm();
1533 
		unsigned freq = getFreq(cha);
1534 
		ch.mod.updateAll(freq, actAsCarrier);
1535 
		ch.car.updateAll(freq, true);
1536 
		break;
1537 
	}
1538 
	case 0x29: case 0x2A: case 0x2B: case 0x2C:
1539 
	case 0x2D: case 0x2E: case 0x2F:
1540 
		r -= 9; // verified on real YM2413
1541 
		[[fallthrough]];
1542 
	case 0x20: case 0x21: case 0x22: case 0x23: case 0x24:
1543 
	case 0x25: case 0x26: case 0x27: case 0x28: {
1544 
		reg[r] = data;
1545 
		unsigned cha = r & 0x0F; assert(cha < 9);
1546 
		Channel& ch = channels[cha];
1547 
		bool modActAsCarrier = (cha >= 7) && isRhythm();
1548 
		ch.setSustain((data >> 5) & 1, modActAsCarrier);
1549 
		if (data & 0x10) {
1550 
			ch.keyOn();
1551 
		} else {
1552 
			ch.keyOff();
1553 
		}
1554 
		unsigned freq = getFreq(cha);
1555 
		ch.mod.updateAll(freq, modActAsCarrier);
1556 
		ch.car.updateAll(freq, true);
1557 
		break;
1558 
	}
1559 
	case 0x39: case 0x3A: case 0x3B: case 0x3C:
1560 
	case 0x3D: case 0x3E: case 0x3F:
1561 
		r -= 9; // verified on real YM2413
1562 
		[[fallthrough]];
1563 
	case 0x30: case 0x31: case 0x32: case 0x33: case 0x34:
1564 
	case 0x35: case 0x36: case 0x37: case 0x38: {
1565 
		reg[r] = data;
1566 
		unsigned cha = r & 0x0F; assert(cha < 9);
1567 
		Channel& ch = channels[cha];
1568 
		if (isRhythm() && (cha >= 6)) {
1569 
			if (cha > 6) {
1570 
				// channel 7 or 8 in rythm mode
1571 
				ch.mod.setVolume(data >> 4);
1572 
			}
1573 
		} else {
1574 
			ch.setPatch(data >> 4, *this);
1575 
		}
1576 
		ch.car.setVolume(data & 15);
1577 
		bool actAsCarrier = (cha >= 7) && isRhythm();
1578 
		unsigned freq = getFreq(cha);
1579 
		ch.mod.updateAll(freq, actAsCarrier);
1580 
		ch.car.updateAll(freq, true);
1581 
		break;
1582 
	}
1583 
	default:
1584 
		break;
1585 
	}
1586 
}
1587
1588 
std::span<const uint8_t, 64> YM2413::peekRegs() const
1589 
{
1590 
	return reg;
1591 
}
1592
1593 
} // namespace YM2413Okazaki
1594
1595 
static constexpr auto envelopeStateInfo = std::to_array<enum_string<YM2413Okazaki::Slot::EnvelopeState>>({
1596 
	{ "ATTACK",  YM2413Okazaki::Slot::EnvelopeState::ATTACK  },
1597 
	{ "DECAY",   YM2413Okazaki::Slot::EnvelopeState::DECAY   },
1598 
	{ "SUSHOLD", YM2413Okazaki::Slot::EnvelopeState::SUSHOLD },
1599 
	{ "SUSTAIN", YM2413Okazaki::Slot::EnvelopeState::SUSTAIN },
1600 
	{ "RELEASE", YM2413Okazaki::Slot::EnvelopeState::RELEASE },
1601 
	{ "SETTLE",  YM2413Okazaki::Slot::EnvelopeState::SETTLE  },
1602 
	{ "FINISH",  YM2413Okazaki::Slot::EnvelopeState::FINISH  },
1603 
});
1604 
SERIALIZE_ENUM(YM2413Okazaki::Slot::EnvelopeState, envelopeStateInfo);
1605
1606 
namespace YM2413Okazaki {
1607
1608 
// version 1: initial version
1609 
// version 2: don't serialize "type / actAsCarrier" anymore, it's now
1610 
//            a calculated value
1611 
// version 3: don't serialize slot_on_flag anymore
1612 
// version 4: don't serialize volume anymore
1613 
template<typename Archive>
1614 
void Slot::serialize(Archive& ar, unsigned /*version*/)
1615 
{
1616 
	ar.serialize("feedback", feedback,
1617 
	             "output",   output,
1618 
	             "cphase",   cPhase,
1619 
	             "state",    state,
1620 
	             "eg_phase", eg_phase,
1621 
	             "sustain",  sustain);
1622
1623 
	// These are restored by calls to
1624 
	//  updateAll():         eg_dPhase, dPhaseDRTableRks, tll, dPhase
1625 
	//  setEnvelopeState():  eg_phase_max
1626 
	//  setPatch():          patch
1627 
	//  setVolume():         volume
1628 
	//  update_key_status(): slot_on_flag
1629 
}
1630
1631 
// version 1: initial version
1632 
// version 2: removed patch_number, freq
1633 
template<typename Archive>
1634 
void Channel::serialize(Archive& ar, unsigned /*version*/)
1635 
{
1636 
	ar.serialize("mod", mod,
1637 
	             "car", car);
1638 
}
1639
1640
1641 
// version 1: initial version
1642 
// version 2: 'registers' are moved here (no longer serialized in base class)
1643 
// version 3: no longer serialize 'user_patch_mod' and 'user_patch_car'
1644 
// version 4: added 'registerLatch'
1645 
template<typename Archive>
1646 
void YM2413::serialize(Archive& ar, unsigned version)
1647 
{
1648 
	if (ar.versionBelow(version, 2)) ar.beginTag("YM2413Core");
1649 
	ar.serialize("registers", reg);
1650 
	if (ar.versionBelow(version, 2)) ar.endTag("YM2413Core");
1651
1652 
	// no need to serialize patches[]
1653 
	//   patches[0] is restored from registers, the others are read-only
1654 
	ar.serialize("channels",   channels,
1655 
	             "pm_phase",   pm_phase,
1656 
	             "am_phase",   am_phase,
1657 
	             "noise_seed", noise_seed);
1658
1659 
	if constexpr (Archive::IS_LOADER) {
1660 
		patches[0][0].initModulator(subspan<8>(reg));
1661 
		patches[0][1].initCarrier  (subspan<8>(reg));
1662 
		for (auto [i, ch] : enumerate(channels)) {
1663 
			// restore patch
1664 
			unsigned p = ((i >= 6) && isRhythm())
1665 
			           ? unsigned(16 + (i - 6))
1666 
			           : (reg[0x30 + i] >> 4);
1667 
			ch.setPatch(p, *this); // before updateAll()
1668 
			// restore volume
1669 
			ch.car.setVolume(reg[0x30 + i] & 15);
1670 
			if (isRhythm() && (i >= 7)) { // ch 7/8 rythm
1671 
				ch.mod.setVolume(reg[0x30 + i] >> 4);
1672 
			}
1673 
			// sync various variables
1674 
			bool actAsCarrier = (i >= 7) && isRhythm();
1675 
			unsigned freq = getFreq(unsigned(i));
1676 
			ch.mod.updateAll(freq, actAsCarrier);
1677 
			ch.car.updateAll(freq, true);
1678 
			ch.mod.setEnvelopeState(ch.mod.state);
1679 
			ch.car.setEnvelopeState(ch.car.state);
1680 
		}
1681 
		update_key_status();
1682 
	}
1683 
	if (ar.versionAtLeast(version, 4)) {
1684 
		ar.serialize("registerLatch", registerLatch);
1685 
	} else {
1686 
		// could be restored from MSXMusicBase, worth the effort?
1687 
	}
1688 
}
1689
1690 
} // namespace YM2413Okazaki
1691
1692 
using YM2413Okazaki::YM2413;
1693 
INSTANTIATE_SERIALIZE_METHODS(YM2413);
1694 
REGISTER_POLYMORPHIC_INITIALIZER(YM2413Core, YM2413, "YM2413-Okazaki");
1695
1696 
} // namespace openmsx