X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=blobdiff_plain;f=firmware%2Fpwm.c;h=da9fe3df679b9feb1faede1ed11205773890a824;hb=64a3d3a699cd60b7a6b4b06c5c38689975a3d460;hp=10c03ba700677a9141ad165ef761357a64f0d3d1;hpb=38a3c5783c24a17e6cf1fbf0af40ae1dec805419;p=bike-lights.git diff --git a/firmware/pwm.c b/firmware/pwm.c index 10c03ba..da9fe3d 100644 --- a/firmware/pwm.c +++ b/firmware/pwm.c @@ -4,10 +4,18 @@ #include "lights.h" -#define PWM_MAX 0x1FF +static uint16_t pwm[N_PWMLEDS]; +static volatile unsigned char step; void init_pwm() { + int i; + + step = 0; + + for (i = 0; i < N_PWMLEDS; i++) + pwm[n] = 0; + /* Async clock */ PLLCSR = _BV(PLLE); @@ -37,8 +45,23 @@ void init_pwm() PORTB &= ~(_BV( PB1 ) | _BV( PB3 ) | _BV( PB5 )); // set to zero } +void susp_pwm() +{ + unsigned char i; + + for (i = 0; i < N_PWMLEDS; i++) + pwm[i] = 0; + + DDRB &= ~(_BV( PB1 ) | _BV( PB3 ) | _BV( PB5 )); + TCCR1D = TCCR1C = TCCR1B = TCCR1A = 0; + TIMSK = 0; + TIFR = 0; +} + void pwm_off(unsigned char n) { + pwm[n] = 0; + switch (n) { case 0: DDRB &= ~_BV(PB1); break; case 1: DDRB &= ~_BV(PB3); break; @@ -46,12 +69,10 @@ void pwm_off(unsigned char n) } } -void pwm_set(unsigned char n, uint16_t stride) +static void pwm_update_hw(unsigned char n) { unsigned char hi, lo; - - if (stride > PWM_MAX) - stride = PWM_MAX; + uint16_t stride = (pwm[n] + step) >> PWM_STEP_SHIFT; if (n == 2) stride = PWM_MAX - stride; @@ -78,6 +99,27 @@ void pwm_set(unsigned char n, uint16_t stride) } } +void pwm_set(unsigned char n, uint16_t stride) +{ + if (((stride + (1 << PWM_STEP_SHIFT)) >> PWM_STEP_SHIFT) >= PWM_MAX) + stride = PWM_MAX << PWM_STEP_SHIFT; + + pwm[n] = stride; + pwm_update_hw(n); +} + +void pwm_timer() +{ + unsigned char i; + + if (++step >= (1 << PWM_STEP_SHIFT)) + step = 0; + + for (i = 0; i < N_PWMLEDS; i++) + if (pwm[n]) + pwm_update_hw(n); +} + #if 0 static void inline pwm_handler() {