|
|
@ -0,0 +1,84 @@ |
|
|
|
#include <stdint.h> |
|
|
|
#include <avr/io.h> |
|
|
|
#include <avr/interrupt.h> |
|
|
|
#include <avr/pgmspace.h> |
|
|
|
#include "led.h" |
|
|
|
#include "sleep_led.h" |
|
|
|
|
|
|
|
/* Software PWM |
|
|
|
* ______ ______ __ |
|
|
|
* | ON |___OFF___| ON |___OFF___| .... |
|
|
|
* |<-------------->|<-------------->|<- .... |
|
|
|
* PWM period PWM period |
|
|
|
* |
|
|
|
* 256 interrupts/period[resolution] |
|
|
|
* 64 periods/second[frequency] |
|
|
|
* 256*64 interrupts/second |
|
|
|
* F_CPU/(256*64) clocks/interrupt |
|
|
|
*/ |
|
|
|
#define SLEEP_LED_TIMER_TOP F_CPU/(256*64) |
|
|
|
|
|
|
|
void sleep_led_init(void) |
|
|
|
{ |
|
|
|
/* Timer1 setup */ |
|
|
|
/* CTC mode */ |
|
|
|
TCCR1B |= _BV(WGM12); |
|
|
|
/* Clock selelct: clk/1 */ |
|
|
|
TCCR1B |= _BV(CS10); |
|
|
|
/* Set TOP value */ |
|
|
|
uint8_t sreg = SREG; |
|
|
|
cli(); |
|
|
|
OCR1AH = (SLEEP_LED_TIMER_TOP>>8)&0xff; |
|
|
|
OCR1AL = SLEEP_LED_TIMER_TOP&0xff; |
|
|
|
SREG = sreg; |
|
|
|
} |
|
|
|
|
|
|
|
void sleep_led_enable(void) |
|
|
|
{ |
|
|
|
/* Enable Compare Match Interrupt */ |
|
|
|
TIMSK1 |= _BV(OCIE1A); |
|
|
|
} |
|
|
|
|
|
|
|
void sleep_led_disable(void) |
|
|
|
{ |
|
|
|
/* Disable Compare Match Interrupt */ |
|
|
|
TIMSK1 &= ~_BV(OCIE1A); |
|
|
|
} |
|
|
|
|
|
|
|
|
|
|
|
/* Breathing Sleep LED brighness(PWM On period) table |
|
|
|
* (32[steps] * 8[duration]) / 64[PWM periods/s] = 4 second breath cycle |
|
|
|
*/ |
|
|
|
static const uint8_t breathing_table[32] PROGMEM = { |
|
|
|
0, 0, 0, 2, 9, 21, 37, 56, 78, 127, 151, 175, 197, 216, 232, 244, |
|
|
|
254, 244, 216, 197, 175, 151, 127, 78, 56, 37, 21, 9, 2, 0, 0, 0 |
|
|
|
}; |
|
|
|
|
|
|
|
ISR(TIMER1_COMPA_vect) |
|
|
|
{ |
|
|
|
/* Software PWM |
|
|
|
* timer:1111 1111 1111 1111 |
|
|
|
* \----/\-/ \-------/+--- count(0-255) |
|
|
|
* | +--------------- duration of step(8) |
|
|
|
* +-------------------- index of step table(0-31) |
|
|
|
*/ |
|
|
|
static union { |
|
|
|
uint16_t row; |
|
|
|
struct { |
|
|
|
uint8_t count:8; |
|
|
|
uint8_t duration:3; |
|
|
|
uint8_t index:5; |
|
|
|
} pwm; |
|
|
|
} timer = { .row = 0 }; |
|
|
|
|
|
|
|
timer.row++; |
|
|
|
|
|
|
|
// LED on |
|
|
|
if (timer.pwm.count == 0) { |
|
|
|
led_set(1<<USB_LED_CAPS_LOCK); |
|
|
|
} |
|
|
|
// LED off |
|
|
|
if (timer.pwm.count == pgm_read_byte(&breathing_table[timer.pwm.index])) { |
|
|
|
led_set(0); |
|
|
|
} |
|
|
|
} |