#include "lights.h"
+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[i] = 0;
+
/* Async clock */
PLLCSR = _BV(PLLE);
;
PLLCSR |= _BV(PCKE);
- TCCR1C = _BV(COM1D0) | _BV(COM1D1) | _BV(PWM1D);
- TCCR1A = _BV(COM1A0) | _BV(COM1A1) | _BV(COM1B0) | _BV(COM1B1) | _BV(PWM1A) | _BV(PWM1B);
- TCCR1B = _BV(7) // PWM1X: PWM inversion mode
- | _BV(CS10) // no clock prescaling
- ;
- TC1H = 0x01;
- OCR1C = 0xFF; // TOP value
+ // PWM channel D is inverted, ...
+ TCCR1C = _BV(COM1D1) | _BV(COM1D0) | _BV(PWM1D);
+ // PWM channels A and B are not
+ TCCR1A = _BV(COM1A1) | _BV(COM1B1) | _BV(PWM1A) | _BV(PWM1B);
+ TCCR1D = 0;
+ TCCR1B = _BV(CS10); // no clock prescaling
+
+ TC1H = PWM_MAX >> 8;
+ OCR1C = PWM_MAX & 0xFF; // TOP value
+
+ TC1H = PWM_MAX >> 8; // PWM3 is inverted
+ OCR1D = PWM_MAX & 0xFF;
TC1H = 0x00;
- OCR1D = OCR1B = OCR1A = 0; // initial stride is 0
+ OCR1B = OCR1A = 0; // initial stride is 0
DDRB &= ~(_BV( PB1 ) | _BV( PB3 ) | _BV( PB5 )); // tristate it
PORTB &= ~(_BV( PB1 ) | _BV( PB3 ) | _BV( PB5 )); // set to zero
}
-void pwm_on(unsigned char n)
+void susp_pwm()
{
- switch (n) {
- case 0: DDRB |= _BV(PB1); break;
- case 1: DDRB |= _BV(PB3); break;
- case 2: DDRB |= _BV(PB5); break;
- }
+ 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;
}
}
-void pwm_set(unsigned char n, unsigned char stride)
+static void pwm_update_hw(unsigned char n)
{
- TC1H = 0x00;
+ unsigned char hi, lo;
+ uint16_t stride = (pwm[n] + step) >> PWM_STEP_SHIFT;
+
+ if (n == 2)
+ stride = PWM_MAX - stride;
+
+ hi = stride >> 8;
+ lo = stride & 0xFF;
+
switch (n) {
- case 0: OCR1A = stride; break;
- case 1: OCR1B = stride; break;
- case 2: OCR1D = stride; break;
+ case 0:
+ TC1H = hi;
+ OCR1A = lo;
+ DDRB |= _BV(PB1);
+ break;
+ case 1:
+ TC1H = hi;
+ OCR1B = lo;
+ DDRB |= _BV(PB3);
+ break;
+ case 2:
+ TC1H = hi;
+ OCR1D = lo;
+ DDRB |= _BV(PB5);
+ break;
}
}
+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[i])
+ pwm_update_hw(i);
+}
+
#if 0
static void inline pwm_handler()
{