X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=tinyboard.git;a=blobdiff_plain;f=projects%2Fstep-up%2Fpwm.c;h=b93a4fab8502039d73d811c69b96592725c5bad5;hp=18a14253552a7c7628f1dc9dde24e1512af83437;hb=HEAD;hpb=3079ccda1c6d82058c801bf8192c616230a2ef93

diff --git a/projects/step-up/pwm.c b/projects/step-up/pwm.c
index 18a1425..b93a4fa 100644
--- a/projects/step-up/pwm.c
+++ b/projects/step-up/pwm.c
@@ -11,10 +11,12 @@
  * Counts from 0 to 0xFF, without OCR1C compare.
  */
 
+volatile unsigned char pwm_enabled;
+
 static void inline enable_pll()
 {
 	/* Async clock */
-	PLLCSR = _BV(PLLE);
+	PLLCSR = _BV(PLLE) | _BV(LSM);
 
 	/* Synchronize to the phase lock */
 	_delay_us(100);
@@ -25,45 +27,48 @@ static void inline enable_pll()
 
 void init_pwm()
 {
+	pwm_enabled = 0;
 	power_timer1_enable();
 
-	enable_pll();
-
-	TCCR1 = _BV(CTC1) | _BV(CS10);	// no clock prescaling
+	TCCR1 = _BV(CTC1) | _BV(CS11);	// pll_clk/2
 	GTCCR = _BV(COM1B1) | _BV(PWM1B);
 
 	OCR1C = PWM_MAX;
 	OCR1B = 0;		// initial stride is 0
 
-	DDRB  &= ~_BV(PB4); // tristate it
+	DDRB &= ~(_BV( PB4 ));
 	PORTB &= ~_BV(PB4); // set to zero
 }
 
-#if 0
 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;
+	DDRB &= ~(_BV( PB4 ));
+	PORTB &= ~(_BV( PB4 ));
+	TCCR1 = 0;
 	TIMSK = 0;
 	TIFR = 0;
 
 	PLLCSR &= ~(_BV(PLLE) | _BV(PCKE));
 }
-#endif
 
 void pwm_off()
 {
 	OCR1B = 0;
 	DDRB &= ~_BV(PB4);
+
+	PLLCSR &= ~(_BV(PLLE) | _BV(PCKE));
+	power_timer1_disable();
+	pwm_enabled = 0;
 }
 
 void pwm_set(uint8_t stride)
 {
 	OCR1B = stride;
-	DDRB |= _BV(PB4);
+
+	if (!pwm_enabled) {
+		power_timer1_enable();
+		enable_pll();
+		DDRB |= _BV(PB4);
+		pwm_enabled = 1;
+	}
 }