1 //  ---------------------------------------------------------------------------
2 //  This file is part of reSID, a MOS6581 SID emulator engine.
3 //  Copyright (C) 2004  Dag Lem <resid@nimrod.no>
4 //
5 //  This program is free software; you can redistribute it and/or modify
6 //  it under the terms of the GNU General Public License as published by
7 //  the Free Software Foundation; either version 2 of the License, or
8 //  (at your option) any later version.
9 //
10 //  This program is distributed in the hope that it will be useful,
11 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 //  GNU General Public License for more details.
14 //
15 //  You should have received a copy of the GNU General Public License
16 //  along with this program; if not, write to the Free Software
17 //  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18 //  ---------------------------------------------------------------------------
19 
20 #ifndef __SID_FP_H__
21 #define __SID_FP_H__
22 
23 #include "siddefs-fp.h"
24 #include "voice.h"
25 #include "filter.h"
26 #include "extfilt.h"
27 #include "pot.h"
28 
29 class SIDFP
30 {
31 public:
32   SIDFP();
33   ~SIDFP();
34 
35   static float kinked_dac(const int x, const float nonlinearity, const int bits);
sse_enabled()36   bool sse_enabled() { return can_use_sse; }
37 
38   void set_chip_model(chip_model model);
get_filter()39   FilterFP& get_filter() { return filter; }
40   void enable_filter(bool enable);
41   void enable_external_filter(bool enable);
42   bool set_sampling_parameters(float clock_freq, sampling_method method,
43                                float sample_freq, float pass_freq = -1);
44   void adjust_sampling_frequency(float sample_freq);
45   void set_voice_nonlinearity(float nonlinearity);
46 
47   void clock();
48   int clock(cycle_count& delta_t, short* buf, int n, int interleave = 1);
49   void reset();
50 
51   // Read/write registers.
52   reg8 read(reg8 offset);
53   void write(reg8 offset, reg8 value);
54 
55   // Read/write state.
56   class State
57   {
58   public:
59     State();
60 
61     char sid_register[0x20];
62 
63     reg8 bus_value;
64     cycle_count bus_value_ttl;
65 
66     reg24 accumulator[3];
67     reg24 shift_register[3];
68     reg16 rate_counter[3];
69     reg16 rate_counter_period[3];
70     reg16 exponential_counter[3];
71     reg16 exponential_counter_period[3];
72     reg8 envelope_counter[3];
73     EnvelopeGeneratorFP::State envelope_state[3];
74     bool hold_zero[3];
75   };
76 
77   State read_state();
78   void write_state(const State& state);
79 
80   // 16-bit input (EXT IN).
81   void input(int sample);
82 
83   // output in range -32768 .. 32767, not clipped (AUDIO OUT)
84   float output();
85 
86 protected:
87   static double I0(double x);
88   RESID_INLINE int clock_interpolate(cycle_count& delta_t, short* buf, int n,
89                                      int interleave);
90   RESID_INLINE int clock_resample_interpolate(cycle_count& delta_t, short* buf,
91                                               int n, int interleave);
92   RESID_INLINE void age_bus_value(cycle_count);
93 
94   VoiceFP voice[3];
95   FilterFP filter;
96   ExternalFilterFP extfilt;
97   PotentiometerFP potx;
98   PotentiometerFP poty;
99 
100   reg8 bus_value;
101   cycle_count bus_value_ttl;
102 
103   float clock_frequency;
104 
105   // External audio input.
106   float ext_in;
107 
108   enum { RINGSIZE = 16384 };
109 
110   // Sampling variables.
111   sampling_method sampling;
112   float cycles_per_sample;
113   float sample_offset;
114   int sample_index;
115   int fir_N;
116   int fir_RES;
117 
118   // Linear interpolation helper
119   float sample_prev;
120 
121   // Ring buffer with overflow for contiguous storage of RINGSIZE samples.
122   float* sample;
123 
124   // FIR_RES filter tables (FIR_N*FIR_RES).
125   float* fir;
126 
127   bool can_use_sse;
128 };
129 
130 #endif // not __SID_H__
131