2009-04-08 21:29:36 +02:00

173 lines
3.5 KiB
C++
Executable File

class aDSP : public DSP {
private:
uint8 dspram[128];
uint8 *spcram;
uint32 dsp_counter;
enum { BRR_END = 1, BRR_LOOP = 2 };
uint8 readb (uint16 addr);
uint16 readw (uint16 addr);
void writeb(uint16 addr, uint8 data);
void writew(uint16 addr, uint16 data);
public:
static const uint16 rate_table[32];
static const int16 gaussian_table[512];
enum EnvelopeStates {
ATTACK,
DECAY,
SUSTAIN,
RELEASE,
SILENCE
};
enum EnvelopeModes {
DIRECT,
LINEAR_DEC,
EXP_DEC,
LINEAR_INC,
BENT_INC,
FAST_ATTACK,
RELEASE_DEC
};
private:
struct Status {
//$0c,$1c
int8 MVOLL, MVOLR;
//$2c,$3c
int8 EVOLL, EVOLR;
//$4c,$5c
uint8 KON, KOFF;
//$6c
uint8 FLG;
//$7c
uint8 ENDX;
//$0d
int8 EFB;
//$2d,$3d,$4d
uint8 PMON, NON, EON;
//$5d
uint8 DIR;
//$6d,$7d
uint8 ESA, EDL;
//$xf
int8 FIR[8];
//internal variables
uint8 kon, esa;
int16 noise_ctr, noise_rate;
uint16 noise_sample;
uint16 echo_index, echo_length;
int16 fir_buffer[2][8];
uint8 fir_buffer_index;
//functions
bool soft_reset() { return !!(FLG & 0x80); }
bool mute() { return !!(FLG & 0x40); }
bool echo_write() { return !(FLG & 0x20); }
} status;
struct Voice {
//$x0-$x1
int8 VOLL, VOLR;
//$x2-$x3
int16 PITCH;
//$x4
uint8 SRCN;
//$x5-$x7
uint8 ADSR1, ADSR2, GAIN;
//$x8-$x9
uint8 ENVX, OUTX;
//internal variables
int16 pitch_ctr;
int8 brr_index;
uint16 brr_ptr;
uint8 brr_header;
bool brr_looped;
int16 brr_data[4];
uint8 brr_data_index;
int16 envx;
uint16 env_ctr, env_rate, env_sustain;
enum EnvelopeStates env_state;
enum EnvelopeModes env_mode;
int16 outx;
//functions
int16 pitch_rate() { return PITCH & 0x3fff; }
uint8 brr_header_shift() { return brr_header >> 4; }
uint8 brr_header_filter() { return (brr_header >> 2) & 3; }
uint8 brr_header_flags() { return brr_header & 3; }
bool ADSR_enabled() { return !!(ADSR1 & 0x80); }
uint8 ADSR_decay() { return (ADSR1 >> 4) & 7; }
uint8 ADSR_attack() { return ADSR1 & 15; }
uint8 ADSR_sus_level() { return ADSR2 >> 5; }
uint8 ADSR_sus_rate() { return ADSR2 & 31; }
void AdjustEnvelope() {
if(env_state == SILENCE) {
env_mode = DIRECT;
env_rate = 0;
envx = 0;
} else if(env_state == RELEASE) {
env_mode = RELEASE_DEC;
env_rate = 0x7800;
} else if(ADSR_enabled()) {
switch(env_state) {
case ATTACK:
env_rate = rate_table[(ADSR_attack() << 1) + 1];
env_mode = (env_rate == 0x7800) ? FAST_ATTACK : LINEAR_INC;
break;
case DECAY:
env_rate = rate_table[(ADSR_decay() << 1) + 0x10];
env_mode = EXP_DEC;
break;
case SUSTAIN:
env_rate = rate_table[ADSR_sus_rate()];
env_mode = (env_rate == 0) ? DIRECT : EXP_DEC;
break;
}
} else if(GAIN & 0x80) {
switch(GAIN & 0x60) {
case 0x00: env_mode = LINEAR_DEC; break;
case 0x20: env_mode = EXP_DEC; break;
case 0x40: env_mode = LINEAR_INC; break;
case 0x60: env_mode = BENT_INC; break;
}
env_rate = rate_table[GAIN & 0x1f];
} else {
env_mode = DIRECT;
env_rate = 0;
envx = (GAIN & 0x7f) << 4;
}
}
} voice[8];
public:
void enter();
void run();
uint8 read (uint8 addr);
void write(uint8 addr, uint8 data);
void power();
void reset();
aDSP();
~aDSP();
};