Change sleep led step table to get smooth

This commit is contained in:
tmk 2013-03-16 23:45:11 +09:00
parent 0142e20bf0
commit db79c1160b
1 changed files with 20 additions and 9 deletions

View File

@ -45,29 +45,40 @@ void sleep_led_disable(void)
TIMSK1 &= ~_BV(OCIE1A);
}
void sleep_led_toggle(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
* (64[steps] * 4[duration]) / 64[PWM periods/s] = 4 second breath cycle
*
* http://www.wolframalpha.com/input/?i=%28sin%28+x%2F64*pi%29**8+*+255%2C+x%3D0+to+63
* (0..63).each {|x| p ((sin(x/64.0*PI)**8)*255).to_i }
*/
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
static const uint8_t breathing_table[64] PROGMEM = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 4, 6, 10,
15, 23, 32, 44, 58, 74, 93, 113, 135, 157, 179, 199, 218, 233, 245, 252,
255, 252, 245, 233, 218, 199, 179, 157, 135, 113, 93, 74, 58, 44, 32, 23,
15, 10, 6, 4, 2, 1, 0, 0, 0, 0, 0, 0, 0, 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)
* \_____/\/ \_______/____ count(0-255)
* \ \______________ duration of step(4)
* \__________________ index of step table(0-63)
*/
static union {
uint16_t row;
struct {
uint8_t count:8;
uint8_t duration:3;
uint8_t index:5;
uint8_t duration:2;
uint8_t index:6;
} pwm;
} timer = { .row = 0 };