/*!
* \file
* <!--
- * Copyright 2003,2004 Develer S.r.l. (http://www.develer.com/)
+ * Copyright 2003, 2004 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.
* -->
* \brief Low-level timer module for AVR
*/
-/*
- * $Log$
- * Revision 1.7 2004/07/20 23:49:40 bernie
- * Compute value of OCR_DIVISOR from CLOCK_FREQ.
- *
- * Revision 1.6 2004/07/20 23:48:16 bernie
- * Finally remove redundant protos.
- *
- * Revision 1.5 2004/07/18 22:16:35 bernie
- * Add missing header; Prevent warning for project_ks-specific code.
- *
- * Revision 1.4 2004/06/27 15:22:15 aleph
- * Fix spacing
- *
- * Revision 1.3 2004/06/07 15:57:40 aleph
- * Update to latest AVR timer code
- *
- * 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 1.21 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 <avr/wdt.h>
+#include <arch_config.h> // ARCH_BOARD_KC
+#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
-#define timer_hw_irq() /* Not needed, IRQ timer flag cleared automatically */
+/*!
+ * 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
+
+
+/* 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
#define OCR_DIVISOR (CLOCK_FREQ / TIMER_PRESCALER / TICKS_PER_SEC - 1) /* 191 */
/*! HW dependent timer initialization */
-#if defined(CONFIG_TIMER_ON_TIMER0)
+#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;
- DISABLE_IRQSAVE(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) | BV(CS02); /* Clear on Compare match & prescaler = 64. When changing
- prescaler change TIMER_HW_HPTICKS_PER_SEC too */
- TCNT0 = 0x00; /* initialization of Timer/Counter */
+ 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);
- ENABLE_IRQRESTORE(flags);
+ IRQ_RESTORE(flags);
}
//! Frequency of the hardware high precision timer
- #define TIMER_HW_HPTICKS_PER_SEC (CLOCK_FREQ / 64)
+ #define TIMER_HW_HPTICKS_PER_SEC (CLOCK_FREQ / TIMER_PRESCALER)
INLINE hptime_t timer_hw_hpread(void)
{
return TCNT0;
}
-#elif defined(CONFIG_TIMER_ON_TIMER1_OVERFLOW)
+#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;
- DISABLE_IRQSAVE(flags);
+ IRQ_SAVE_DISABLE(flags);
/* Reset Timer overflow flag */
TIFR |= BV(TOV1);
/* Enable timer interrupt: Timer/Counter1 Overflow */
TIMSK |= BV(TOIE1);
- ENABLE_IRQRESTORE(flags);
+ IRQ_RESTORE(flags);
}
//! Frequency of the hardware high precision timer
return TCNT1;
}
-#elif defined(CONFIG_TIMER_ON_TIMER2)
+#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;
- DISABLE_IRQSAVE(flags);
+ IRQ_SAVE_DISABLE(flags);
/* Reset Timer flags */
TIFR = BV(OCF2) | BV(TOV2);
/* Setup Timer/Counter interrupt */
- TCCR2 = BV(WGM21) | BV(CS21) | BV(CS20);
+ 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 */
TIMSK &= ~BV(TOIE2);
TIMSK |= BV(OCIE2);
- ENABLE_IRQRESTORE(flags);
+ IRQ_RESTORE(flags);
}
//! Frequency of the hardware high precision timer
- #define TIMER_HW_HPTICKS_PER_SEC (CLOCK_FREQ / 64)
+ #define TIMER_HW_HPTICKS_PER_SEC (CLOCK_FREQ / TIMER_PRESCALER)
INLINE hptime_t timer_hw_hpread(void)
{
}
#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)
*/
SIGNAL(SIG_OVERFLOW1)
{
- /*!
- * 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
-
- static uint8_t count = TIMER1_OVF_COUNT;
-
- count--;
- if (!count)
- {
- timer_handler();
- count = TIMER1_OVF_COUNT;
- }
-
#if (ARCH & ARCH_BOARD_KC)
/*
* Super-optimization-hack: switch CPU ADC mux here, ASAP after 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)
{
- TIMER_STROBE_ON;
+ /*
+ * 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(ADFR) | BV(ADIF) | BV(ADSC));
+
ADC_SETCHN(_adc_idx_next);
- TIMER_STROBE_OFF;
_adc_trigger_lock = true;
}
- #endif
+ #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 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 */
projects / bertos.git / blobdiff