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#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>
#include "ringbuf_small.h"
#include "ringbuf_small.c"
#include "mmc.h"
#include "gg.h"
void timer_init_tiny26(void)
{
PLLCSR = 1 << PLLE;/* pll enable */
_delay_us(100);
while(!(PLLCSR & (1 << PLOCK))) {;}/* wait for lock */
PLLCSR |= 1 << PCKE;/* use pll */
OCR1C = 0xff;/* unused */
/* output pin: OC1A = PB1 = 1 or OC1B = PB3 = 2 */
OCR1B = 0x66;
cnt_to_next = 1;/* overflows to next sample */
TCCR1A = (1 << COM1B1) | (1 << PWM1B);/* pwm enable, not inverted */
TCCR1B = (1 << CS11);/* fast pwm, prescaler / 2 */
DDRB |= (1 << PB3);
TIMSK = 1 << TOIE1;/* interrupt on overflow */
}
#define BUFFER_SIZE 16
uint16_t buffer[BUFFER_SIZE];/* buffer for mmc data */
ringbuf_t rb;
int32_t length;/* remaining samples */
/*ISR(TIMER1_OVF1_vect, ISR_NAKED)
{
__asm__("in r2, 0x3f"); // save sreg
if(--cnt_to_ocr_incr){
OCR1A = cur_ocr + 1;
}
if(--cnt_to_next){
cur_ocr = next_ocr;
OCR1A = cur_ocr;
cnt_to_ocr_incr = next_cnt_to_incr;
cnt_to_next = 8;
needs_new_data_flag = 1;
}
__asm__("out 0x3f,r2"); // restore sreg
reti();
}// */
ISR(TIMER1_OVF1_vect){
// next try: simplistic, not too much looking at speed
uint16_t next = 0;
// OCR1B += 1; // test pwm
if(!--cnt_to_next){
ringbuf_get(&rb, &next);
OCR1B = (next>>8);
cnt_to_ocr_incr = 8 - ((next>>5) & 0x7);
cnt_to_next = 8;
/* if(!--length)
{
// shut down
PORTA &= ~(1 << PA7);
}*/
} else {
if(!--cnt_to_ocr_incr){
OCR1B += 1;
}
}
}
int main(void) __attribute__((noreturn));
int main(void)
{
_delay_ms(30); // wait for card to get power
uint8_t debug=0;
DDRA |= (1 << PA7);
PORTA &= ~(1 << PA7);
ringbuf_init(&rb, buffer, BUFFER_SIZE);
debug = 1;
// while(debug){
debug=mmc_init();
// }
debug = 2-debug;
timer_init_tiny26();
sei();
_delay_ms(1);
mmc_read_part(0, (unsigned char *) &length, 4);
// char_to_sound(length&0xff);
unsigned long block = 0;
while(length > 0)
{
//mmc_read_to_ringbuffer(block, &rb);
mmc_read_to_ringbuffer(block, &rb);
length -= 256;
block++;
} // */
// debug = 0;
// shut down
PORTA |= (1 << PA7);
DDRA &= ~(1 << PA7);
for(;;);
}
void char_to_sound(uint8_t val){
uint8_t i=0,r,b, sound=10;
uint16_t a,to;
for(b=0; b<8; b++){
/* if(val & 0x80){
sound = 2;
}else{
sound = 1;
}// */
sound = (val&1)+1;
val >>= 1;
for(to=0; to<3200; to++){
i += sound*8;
a = i<<8;
r=1;
while(r){
r=ringbuf_put(&rb, a);
}
}
for(to=0; to<800; to++){
r=1;
while(r){
r=ringbuf_put(&rb, 0);
}
}
}
for(to=0; to<4000; to++){
r=1;
while(r){
r=ringbuf_put(&rb, 0);
}
}
}