X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=drv%2Ftimer_avr.h;h=7442fdcb152e335d3376a64a54fe1f37e65802aa;hb=ffd018661b93d258df699ee4e86d0f2f1cccba4e;hp=d308608aedf3adca7e2553912a64ca325511b92b;hpb=af9c555446161016fdd76c1cdff96ce76bb6cba2;p=bertos.git

diff --git a/drv/timer_avr.h b/drv/timer_avr.h
index d308608a..7442fdcb 100755
--- a/drv/timer_avr.h
+++ b/drv/timer_avr.h
@@ -1,4 +1,4 @@
-/*!
+/**
  * \file
  * <!--
  * Copyright 2003, 2004, 2005 Develer S.r.l. (http://www.develer.com/)
@@ -9,12 +9,25 @@
  * \version $Id$
  *
  * \author Bernardo Innocenti <bernie@develer.com>
+ * \author Francesco Sacchi <batt@develer.com>
  *
- * \brief Low-level timer module for AVR
+ * \brief Low-level timer module for AVR (interface).
  */
 
 /*#*
  *#* $Log$
+ *#* Revision 1.28  2006/07/19 12:56:26  bernie
+ *#* Convert to new Doxygen style.
+ *#*
+ *#* Revision 1.27  2006/05/18 00:38:24  bernie
+ *#* Use hw_cpu.h instead of ubiquitous hw.h.
+ *#*
+ *#* Revision 1.26  2006/02/21 21:28:02  bernie
+ *#* New time handling based on TIMER_TICKS_PER_SEC to support slow timers with ticks longer than 1ms.
+ *#*
+ *#* Revision 1.25  2005/07/19 07:26:37  bernie
+ *#* Refactor to decouple timer ticks from milliseconds.
+ *#*
  *#* Revision 1.24  2005/04/11 19:10:28  bernie
  *#* Include top-level headers from cfg/ subdir.
  *#*
@@ -32,281 +45,95 @@
  *#*
  *#* Revision 1.18  2004/09/20 03:31:03  bernie
  *#* Fix racy racy code.
- *#*
- *#* Revision 1.17  2004/09/14 21:07:09  bernie
- *#* Include hw.h explicitly.
- *#*
- *#* Revision 1.16  2004/09/06 21:49:26  bernie
- *#* CONFIG_TIMER_STROBE: be tolerant with missing optional macro.
- *#*
- *#* Revision 1.15  2004/08/25 14:12:08  rasky
- *#* Aggiornato il comment block dei log RCS
- *#*
- *#* Revision 1.14  2004/08/24 16:27:01  bernie
- *#* Add missing headers.
- *#*
- *#* Revision 1.13  2004/08/24 14:30:11  bernie
- *#* Use new-style config macros for drv/timer.c
- *#*
- *#* Revision 1.12  2004/08/10 06:59:45  bernie
- *#* CONFIG_TIMER_STROBE: Define no-op default macros.
- *#*
- *#* Revision 1.11  2004/08/03 15:53:17  aleph
- *#* Fix spacing
- *#*
- *#* Revision 1.10  2004/08/02 20:20:29  aleph
- *#* Merge from project_ks
- *#*
- *#* Revision 1.9  2004/07/22 02:01:14  bernie
- *#* Use TIMER_PRESCALER consistently.
  *#*/
 #ifndef DRV_TIMER_AVR_H
 #define DRV_TIMER_AVR_H
 
-#include <cfg/arch_config.h> // ARCH_BOARD_KC
-#include <cfg/macros.h> // BV()
-#include <hw.h>
+#include <appconfig.h>     /* CONFIG_TIMER */
+#include <cfg/compiler.h>  /* uint8_t */
+#include <hw_cpu.h>        /* CLOCK_FREQ */
 
-#include <avr/signal.h>
-#include <avr/io.h>
-
-#if defined(ARCH_BOARD_KC) && (ARCH & ARCH_BOARD_KC)
-	#include <drv/adc.h>
-#endif
-
-
-/*!
- * Values for CONFIG_TIMER.
+/**
+ * \name Values for CONFIG_TIMER.
  *
  * Select which hardware timer interrupt to use for system clock and softtimers.
  * \note The timer 1 overflow mode set the timer as a 24 kHz PWM.
+ *
+ * \{
  */
 #define TIMER_ON_OUTPUT_COMPARE0  1
 #define TIMER_ON_OVERFLOW1        2
 #define TIMER_ON_OUTPUT_COMPARE2  3
+#define TIMER_ON_OVERFLOW3        4
+/* \} */
 
-
-/* Not needed, IRQ timer flag cleared automatically */
-#define timer_hw_irq() do {} while (0)
-
-#define TIMER_PRESCALER 64
-
-/*!
- * System timer: additional division after the prescaler
- * 12288000 / 64 / 192 (0..191) = 1 ms
+/*
+ * Hardware dependent timer initialization.
  */
-#define OCR_DIVISOR  (CLOCK_FREQ / TIMER_PRESCALER / TICKS_PER_SEC - 1) /* 191 */
-
-/*! HW dependent timer initialization  */
 #if (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE0)
 
-	//! Type of time expressed in ticks of the hardware high-precision timer
-	typedef uint8_t hptime_t;
-
-	static void timer_hw_init(void)
-	{
-		cpuflags_t flags;
-		IRQ_SAVE_DISABLE(flags);
+	#define TIMER_PRESCALER      64
+	#define TIMER_HW_BITS        8
+	#define DEFINE_TIMER_ISR     SIGNAL(SIG_OUTPUT_COMPARE0)
+	#define TIMER_TICKS_PER_SEC  1000
+	#define TIMER_HW_CNT         OCR_DIVISOR
 
-		/* Reset Timer flags */
-		TIFR = BV(OCF0) | BV(TOV0);
-
-		/* Setup Timer/Counter interrupt */
-		ASSR = 0x00;                  /* Internal system clock */
-		TCCR0 = BV(WGM01)             /* Clear on Compare match */
-			#if TIMER_PRESCALER == 64
-				| BV(CS02)
-			#else
-				#error Unsupported value of TIMER_PRESCALER
-			#endif
-		;
-		TCNT0 = 0x00;                 /* Initialization of Timer/Counter */
-		OCR0 = OCR_DIVISOR;           /* Timer/Counter Output Compare Register */
-
-		/* Enable timer interrupts: Timer/Counter2 Output Compare (OCIE2) */
-		TIMSK &= ~BV(TOIE0);
-		TIMSK |= BV(OCIE0);
-
-		IRQ_RESTORE(flags);
-	}
-
-	//! Frequency of the hardware high precision timer
-	#define TIMER_HW_HPTICKS_PER_SEC  (CLOCK_FREQ / TIMER_PRESCALER)
-
-	INLINE hptime_t timer_hw_hpread(void)
-	{
-		return TCNT0;
-	}
+	/// Type of time expressed in ticks of the hardware high-precision timer
+	typedef uint8_t hptime_t;
 
 #elif (CONFIG_TIMER == TIMER_ON_OVERFLOW1)
 
-	//! Type of time expressed in ticks of the hardware high precision timer
-	typedef uint16_t hptime_t;
-
-	static void timer_hw_init(void)
-	{
-		cpuflags_t flags;
-		IRQ_SAVE_DISABLE(flags);
+	#define TIMER_PRESCALER      1
+	#define TIMER_HW_BITS        8
+	/** This value is the maximum in overflow based timers. */
+	#define TIMER_HW_CNT         (1 << TIMER_HW_BITS)
+	#define DEFINE_TIMER_ISR     SIGNAL(SIG_OVERFLOW1)
+	#define TIMER_TICKS_PER_SEC  ((TIMER_HW_HPTICKS_PER_SEC + TIMER_HW_CNT / 2) / TIMER_HW_CNT)
 
-		/* Reset Timer overflow flag */
-		TIFR |= BV(TOV1);
-
-		/* Fast PWM mode, 9 bit, 24 kHz, no prescaling. When changing freq or
-		   resolution (top of TCNT), change TIMER_HW_HPTICKS_PER_SEC too */
-		TCCR1A |= BV(WGM11);
-		TCCR1A &= ~BV(WGM10);
-		TCCR1B |= BV(WGM12) | BV(CS10);
-		TCCR1B &= ~(BV(WGM13) | BV(CS11) | BV(CS12));
-
-		TCNT1 = 0x00;         /* initialization of Timer/Counter */
-
-		/* Enable timer interrupt: Timer/Counter1 Overflow */
-		TIMSK |= BV(TOIE1);
-
-		IRQ_RESTORE(flags);
-	}
-
-	//! Frequency of the hardware high precision timer
-	#define TIMER_HW_HPTICKS_PER_SEC  (24000ul * 512)
-
-	INLINE hptime_t timer_hw_hpread(void)
-	{
-		return TCNT1;
-	}
+	/// Type of time expressed in ticks of the hardware high precision timer
+	typedef uint16_t hptime_t;
 
 #elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE2)
 
-	//! Type of time expressed in ticks of the hardware high precision timer
-	typedef uint8_t hptime_t;
-
-	static void timer_hw_init(void)
-	{
-		cpuflags_t flags;
-		IRQ_SAVE_DISABLE(flags);
+	#define TIMER_PRESCALER      64
+	#define TIMER_HW_BITS        8
+	#define DEFINE_TIMER_ISR     SIGNAL(SIG_OUTPUT_COMPARE2)
+	#define TIMER_TICKS_PER_SEC  1000
+	/** Value for OCR register in output-compare based timers. */
+	#define TIMER_HW_CNT         OCR_DIVISOR
 
-		/* Reset Timer flags */
-		TIFR = BV(OCF2) | BV(TOV2);
 
-		/* Setup Timer/Counter interrupt */
-		TCCR2 = BV(WGM21)
-			#if TIMER_PRESCALER == 64
-				| BV(CS21) | BV(CS20)
-			#else
-				#error Unsupported value of TIMER_PRESCALER
-			#endif
-		;
-		/* Clear on Compare match & prescaler = 64, internal sys clock.
-		   When changing prescaler change TIMER_HW_HPTICKS_PER_SEC too */
-		TCNT2 = 0x00;         /* initialization of Timer/Counter */
-		OCR2 = OCR_DIVISOR;   /* Timer/Counter Output Compare Register */
-
-		/* Enable timer interrupts: Timer/Counter2 Output Compare (OCIE2) */
-		TIMSK &= ~BV(TOIE2);
-		TIMSK |= BV(OCIE2);
-
-		IRQ_RESTORE(flags);
-	}
+	/// Type of time expressed in ticks of the hardware high precision timer
+	typedef uint8_t hptime_t;
 
-	//! Frequency of the hardware high precision timer
-	#define TIMER_HW_HPTICKS_PER_SEC  (CLOCK_FREQ / TIMER_PRESCALER)
+#elif (CONFIG_TIMER == TIMER_ON_OVERFLOW3)
 
-	INLINE hptime_t timer_hw_hpread(void)
-	{
-		return TCNT2;
-	}
+	#define TIMER_PRESCALER      1
+	#define TIMER_HW_BITS        8
+	/** This value is the maximum in overflow based timers. */
+	#define TIMER_HW_CNT         (1 << TIMER_HW_BITS)
+	#define DEFINE_TIMER_ISR     SIGNAL(SIG_OVERFLOW3)
+	#define TIMER_TICKS_PER_SEC  ((TIMER_HW_HPTICKS_PER_SEC + TIMER_HW_CNT / 2) / TIMER_HW_CNT)
 
+	/// Type of time expressed in ticks of the hardware high precision timer
+	typedef uint16_t hptime_t;
 #else
+
 	#error Unimplemented value for CONFIG_TIMER
 #endif /* CONFIG_TIMER */
 
 
-#if (CONFIG_TIMER == TIMER_ON_OVERFLOW1)
-
-	#define DEFINE_TIMER_ISR	\
-		static void timer_handler(void)
-
-	DEFINE_TIMER_ISR;
-
-	/*
-	 * Timer 1 overflow irq handler. It's called at the frequency of the timer 1
-	 * PWM (should be 24 kHz). It's too much for timer purposes, so the interrupt
-	 * handler is really a counter that call the true handler in timer.c
-	 * every 1 ms.
-	 */
-	SIGNAL(SIG_OVERFLOW1)
-	{
-	#if (ARCH & ARCH_BOARD_KC)
-		/*
-		 * Super-optimization-hack: switch CPU ADC mux here, ASAP after the start
-		 * of conversion (auto-triggered with timer 1 overflow).
-		 * The switch can be done 2 ADC cycles after start of conversion.
-		 * The handler prologue takes a little more than 32 CPU cycles: with
-		 * the prescaler at 1/16 the timing should be correct even at the start
-		 * of the handler.
-		 *
-		 * The switch is synchronized with the ADC handler using _adc_trigger_lock.
-		 *
-		 *      Mel (A Real Programmer)
-		 */
-		extern uint8_t _adc_idx_next;
-		extern bool _adc_trigger_lock;
+/** Frequency of the hardware high precision timer. */
+#define TIMER_HW_HPTICKS_PER_SEC  ((CLOCK_FREQ + TIMER_PRESCALER / 2) / TIMER_PRESCALER)
 
-		if (!_adc_trigger_lock)
-		{
-			// Backwards compatibility fix for avr-libc 1.0.4
-			#ifndef ADATE
-			#define ADATE ADFR
-			#endif
-
-			/*
-			 * Disable free-running mode to avoid starting a
-			 * new conversion before the ADC handler has read
-			 * the ongoing one.  This condition could occur
-			 * under very high interrupt load and would have the
-			 * unwanted effect of reading from the wrong ADC
-			 * channel.
-			 *
-			 * NOTE: writing 0 to ADSC and ADIF has no effect.
-			 */
-			ADCSRA = ADCSRA & ~(BV(ADATE) | BV(ADIF) | BV(ADSC));
-
-			ADC_SETCHN(_adc_idx_next);
-			_adc_trigger_lock = true;
-		}
-	#endif // ARCH_BOARD_KC
-
-		/*!
-		 * How many timer overflows we must count before calling the real
-		 * timer handler.
-		 * When the timer is programmed to overflow at 24 kHz, a value of
-		 * 24 will result in 1ms between each call.
-		 */
-		#define TIMER1_OVF_COUNT 24
-		//#warning TIMER1_OVF_COUNT for timer at 12 kHz
-		//#define TIMER1_OVF_COUNT 12
-
-		static uint8_t count = TIMER1_OVF_COUNT;
-
-		count--;
-		if (!count)
-		{
-			timer_handler();
-			count = TIMER1_OVF_COUNT;
-		}
-	}
-
-#elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE0)
-
-	#define DEFINE_TIMER_ISR	\
-		SIGNAL(SIG_OUTPUT_COMPARE0)
-
-#elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE2)
+/**
+ * System timer: additional division after the prescaler
+ * 12288000 / 64 / 192 (0..191) = 1 ms
+ */
+#define OCR_DIVISOR  (((CLOCK_FREQ + TIMER_PRESCALER / 2) / TIMER_PRESCALER + TIMER_TICKS_PER_SEC / 2) / TIMER_TICKS_PER_SEC - 1)
 
-	#define DEFINE_TIMER_ISR	\
-		SIGNAL(SIG_OUTPUT_COMPARE2)
+/** Not needed, IRQ timer flag cleared automatically */
+#define timer_hw_irq() do {} while (0)
 
-#else
-	#error Unimplemented value for CONFIG_TIMER
-#endif /* CONFIG_TIMER */
 
 #endif /* DRV_TIMER_AVR_H */