/*!
* \file
* <!--
- * Copyright 2003,2004 Develer S.r.l. (http://www.develer.com/)
+ * Copyright 2003, 2004, 2005 Develer S.r.l. (http://www.develer.com/)
* Copyright 2000 Bernardo Innocenti <bernie@develer.com>
- * This file is part of DevLib - See devlib/README for information.
+ * This file is part of DevLib - See README.devlib for information.
* -->
*
* \version $Id$
* \brief Low-level timer module for AVR
*/
-/*
- * $Log$
- * Revision 1.2 2004/06/03 11:27:09 bernie
- * Add dual-license information.
- *
- * Revision 1.1 2004/05/23 18:23:30 bernie
- * Import drv/timer module.
+/*#*
+ *#* $Log$
+ *#* Revision 1.24 2005/04/11 19:10:28 bernie
+ *#* Include top-level headers from cfg/ subdir.
+ *#*
+ *#* Revision 1.23 2005/03/01 23:24:51 bernie
+ *#* Tweaks for avr-libc 1.2.x.
+ *#*
+ *#* Revision 1.21 2004/12/13 12:07:06 bernie
+ *#* DISABLE_IRQSAVE/ENABLE_IRQRESTORE: Convert to IRQ_SAVE_DISABLE/IRQ_RESTORE.
+ *#*
+ *#* Revision 1.20 2004/11/16 20:59:46 bernie
+ *#* Include <avr/io.h> explicitly.
+ *#*
+ *#* Revision 1.19 2004/10/19 08:56:41 bernie
+ *#* TIMER_STROBE_ON, TIMER_STROBE_OFF, TIMER_STROBE_INIT: Move from timer_avr.h to timer.h, where they really belong.
+ *#*
+ *#* 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 <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.
*
+ * 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
-#ifndef DRV_TIMER_AVR_H
-#define DRV_TIMER_AVR_H
-#include <avr/wdt.h>
+/* Not needed, IRQ timer flag cleared automatically */
+#define timer_hw_irq() do {} while (0)
-# define TIMER_RETRIGGER /* Not needed, timer retriggers automatically */
+#define TIMER_PRESCALER 64
- /*!
- * System timer: additional division after the prescaler
- * 12288000 / 64 / 192 (0..191) = 1 ms
- */
-# define OCR_DIVISOR 191
-
- /*! HW dependent timer initialization */
-#if defined(CONFIG_TIMER_ON_TIMER0)
-
-# define TIMER_INIT \
- do { \
- DISABLE_INTS; \
- \
- /* Reset Timer flags */ \
- TIFR = BV(OCF0) | BV(TOV0); \
- \
- /* Setup Timer/Counter interrupt */ \
- ASSR = 0x00; /* internal system clock */ \
- TCCR0 = BV(WGM01) | BV(CS02); /* Clear on Compare match & prescaler = 64 */ \
- 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); \
- \
- ENABLE_INTS; \
- } while (0)
-
-#elif defined(CONFIG_TIMER_ON_TIMER1_OVERFLOW)
-
-# define TIMER_INIT \
- do { \
- DISABLE_INTS; \
- \
- /* Reset Timer overflow flag */ \
- TIFR |= BV(TOV1); \
- \
- /* Fast PWM mode, 24 kHz, no prescaling */ \
- 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); \
- \
- ENABLE_INTS; \
- } while (0)
-
-#elif defined(CONFIG_TIMER_ON_TIMER2)
-
-# define TIMER_INIT \
- do { \
- DISABLE_INTS; \
- \
- /* Reset Timer flags */ \
- TIFR = BV(OCF2) | BV(TOV2); \
- \
- /* Setup Timer/Counter interrupt */ \
- TCCR2 = BV(WGM21) | BV(CS21) | BV(CS20); \
- /* Clear on Compare match & prescaler = 64, internal sys clock */ \
- 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); \
- \
- ENABLE_INTS; \
- } while (0)
+/*!
+ * System timer: additional division after the prescaler
+ * 12288000 / 64 / 192 (0..191) = 1 ms
+ */
+#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);
+
+ /* 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;
+ }
+
+#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);
+
+ /* 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;
+ }
+
+#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);
+
+ /* 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);
+ }
+
+ //! 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 TCNT2;
+ }
#else
-# error Choose witch timer to use with CONFIG_TIMER_ON_TIMERx
-#endif /* CONFIG_TIMER_ON_TIMERx */
+ #error Unimplemented value for CONFIG_TIMER
+#endif /* CONFIG_TIMER */
-#if defined(CONFIG_TIMER_ON_TIMER1_OVERFLOW)
+#if (CONFIG_TIMER == TIMER_ON_OVERFLOW1)
#define DEFINE_TIMER_ISR \
static void timer_handler(void)
+ DEFINE_TIMER_ISR;
+
/*
- * Timer 1 overflow irq handler.
- */
+ * 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;
+
+ 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 overflow we have to count before calling the true timer handler.
- * If timer overflow is at 24 kHz, with a value of 24 we have 1 ms between
- * each call.
- */
- #define TIMER1_OVF_COUNT 24
+ * 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;
}
}
-#elif defined (CONFIG_TIMER_ON_TIMER0)
+#elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE0)
#define DEFINE_TIMER_ISR \
SIGNAL(SIG_OUTPUT_COMPARE0)
-#elif defined(CONFIG_TIMER_ON_TIMER2)
+#elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE2)
#define DEFINE_TIMER_ISR \
SIGNAL(SIG_OUTPUT_COMPARE2)
#else
-# error Choose witch timer to use with CONFIG_TIMER_ON_TIMERx
-#endif /* CONFIG_TIMER_ON_TIMERx */
+ #error Unimplemented value for CONFIG_TIMER
+#endif /* CONFIG_TIMER */
#endif /* DRV_TIMER_AVR_H */