Files

82 lines
1.9 KiB
C

/*Include file for ADSR synth project. */
#include <avr/io.h> /* Defines pins, ports, etc */
#include <util/delay.h> /* Functions to waste time */
#include <avr/power.h>
#include <avr/interrupt.h>
#include "pinDefines.h"
#include "macros.h"
#include "scale.h"
#include "fullSaw7.h" /* a 7-harmonic bandlimited sawtooth */
/* see generateWavetables.py if you're interested */
#include "fullTriangle.h"
#include "USART.h"
#define FULL_VOLUME 31 /* 5-bit volumes */
// Default envelope values (slightly percussive)
// Play around with these!
#define ATTACK_RATE 8 /* 0-255 */
#define DECAY_RATE 120 /* 0-255 */
#define SUSTAIN_LEVEL 25 /* 0-255 */
#define SUSTAIN_TIME 4000 /* 0-65535 */
#define RELEASE_RATE 200 /* 0-65535 */
// Compute these constants
#define ATTACK_TIME ATTACK_RATE * FULL_VOLUME
#define DECAY_TIME (ATTACK_TIME + (FULL_VOLUME-SUSTAIN_LEVEL) * DECAY_RATE)
#define RELEASE_TIME DECAY_TIME + SUSTAIN_TIME
// -------------- Init Routines --------------- //
static inline void initTimer0(void){
set_bit(TCCR0A, COM0A1); /* PWM output on OCR0A */
set_bit(SPEAKER_DDR, SPEAKER); /* enable output on pin */
set_bit(TCCR0A, WGM00); /* Fast PWM mode */
set_bit(TCCR0A, WGM01); /* Fast PWM mode, pt.2 */
set_bit(TCCR0B, CS00); /* Clock with /1 prescaler */
}
static inline void initLEDs(void){
uint8_t i;
LED_DDR = 0xff; /* All LEDs for diagnostics */
for (i=0; i<8; i++){
set_bit(LED_PORT, i);
_delay_ms(100);
clear_bit(LED_PORT, i);
}
}
static inline uint16_t lookupPitch(char i){
switch(i){
case 'a':
return(G1);
case 's':
return(A1);
case 'd':
return(B1);
case 'f':
return(C2);
case 'g':
return(D2);
case 'h':
return(E2);
case 'j':
return(F2);
case 'k':
return(G2);
case 'l':
return(A2);
case ';':
return(B2);
case '\'':
return(C3);
}
// Default value -- if press some other key
return(C1);
}