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slow donw, put stuff into header

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This commit is contained in:
twobit 2012-08-08 03:24:21 +02:00
parent f37519c06f
commit eef4ec0e44
3 changed files with 32 additions and 38 deletions
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2
firmware/main.c
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@ -18,7 +18,7 @@ static void init_sampletimer(void)
TCCR0A = (1 << WGM01); TCCR0A = (1 << WGM01);
TCCR0B = (1 << CS00) | (1 << CS01); TCCR0B = (1 << CS00) | (1 << CS01);
OCR0A = 3; /* TOP */ OCR0A = 6; /* TOP */
TCNT0 = 0; TCNT0 = 0;
/*enable interrupt*/ /*enable interrupt*/
TIMSK0 |= (1<<OCIE0A); TIMSK0 |= (1<<OCIE0A);

43
firmware/synth.c
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@ -1,36 +1,15 @@
#include <inttypes.h> #include <inttypes.h>
#include "synth.h"
#include "freq_table.h" #include "freq_table.h"
// sample rate is 8M / (3 * 64) // sample rate is 8M / (3 * 64)
enum { WAVE_OFF, WAVE_PULSE, WAVE_SAW, WAVE_NOISE };
enum { enum {
channel_count = 3, channel_count = 3,
tick_length = 800, tick_length = 400,
row_length = 4, row_length = 4,
pattern_length = 16 pattern_length = 16
}; };
typedef struct {
uint8_t note;
uint8_t inst_nr;
uint8_t pos;
uint16_t phase;
uint16_t pulse_width;
uint8_t level; // envelop level
} synth_channel_t;
typedef struct {
uint16_t pulse_width;
uint8_t pulse_sweep;
uint8_t wave_table_pos;
uint8_t decay;
} synth_instrument_t;
static const synth_instrument_t instruments[] = { static const synth_instrument_t instruments[] = {
@ -68,9 +47,9 @@ static const uint8_t patterns[][pattern_length][2] = {
{}, {},
{ {
{ 33 - 12, 0 }, { 33 - 12, 0 },
{ 0, 0 },
{ 0xff, 1 }, { 0xff, 1 },
{ 33 - 12, 1 }, { 0, 0 },
{ 0xff, 1 },
{ 33, 1 }, { 33, 1 },
{ 0xff, 1 }, { 0xff, 1 },
{ 33, 1 }, { 33, 1 },
@ -86,9 +65,9 @@ static const uint8_t patterns[][pattern_length][2] = {
}, },
{ {
{ 28 - 12, 0 }, { 28 - 12, 0 },
{ 0, 0 },
{ 0xff, 1 }, { 0xff, 1 },
{ 28 - 12, 1 }, { 0, 0 },
{ 0xff, 1 },
{ 28, 1 }, { 28, 1 },
{ 0xff, 1 }, { 0xff, 1 },
{ 28, 1 }, { 28, 1 },
@ -202,14 +181,6 @@ void synth_init(void)
tick = 0; tick = 0;
row = 0; row = 0;
seq = 0; seq = 0;
/*
// some test values
channels[0].wave = WAVE_PULSE;
channels[0].pulse_width = 1 << 15;
channels[1].wave = WAVE_SAW;
*/
} }
uint16_t synth_mix(void) uint16_t synth_mix(void)
@ -239,7 +210,7 @@ uint16_t synth_mix(void)
if(note == 0xff) { if(note == 0xff) {
chan->level = 0; chan->level = 0;
} else { } else {
chan->level = 100; chan->level = 80; // TODO: less?
chan->note = note; chan->note = note;
chan->inst_nr = patterns[pattern_nr][row][1]; chan->inst_nr = patterns[pattern_nr][row][1];
inst = &instruments[chan->inst_nr]; inst = &instruments[chan->inst_nr];

23
firmware/synth.h
View File

@ -1,3 +1,26 @@
enum { WAVE_OFF, WAVE_PULSE, WAVE_SAW, WAVE_NOISE };
typedef struct {
uint8_t note;
uint8_t inst_nr;
uint8_t pos;
uint16_t phase;
uint16_t pulse_width;
uint8_t level; // envelop level
} synth_channel_t;
typedef struct {
uint16_t pulse_width;
uint8_t pulse_sweep;
uint8_t wave_table_pos;
uint8_t decay;
} synth_instrument_t;
void synth_init(void); void synth_init(void);
uint16_t synth_mix(void); uint16_t synth_mix(void);