diff options
Diffstat (limited to 'common')
| -rw-r--r-- | common/sleep_led.c | 84 | ||||
| -rw-r--r-- | common/sleep_led.h | 10 |
2 files changed, 94 insertions, 0 deletions
diff --git a/common/sleep_led.c b/common/sleep_led.c new file mode 100644 index 0000000000..edf68c3523 --- /dev/null +++ b/common/sleep_led.c @@ -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); + } +} diff --git a/common/sleep_led.h b/common/sleep_led.h new file mode 100644 index 0000000000..aebdbeaa5a --- /dev/null +++ b/common/sleep_led.h @@ -0,0 +1,10 @@ +#ifndef SLEEP_LED_H +#define SLEEP_LED_H + +#define NO_SUSPEND_POWER_DOWN + +void sleep_led_init(void); +void sleep_led_enable(void); +void sleep_led_disable(void); + +#endif |