MicroAPRS/bertos/cpu/avr/drv/timer_mega.c

258 lines
7.2 KiB
C

/**
* \file
* <!--
* This file is part of BeRTOS.
*
* Bertos is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
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* file does not by itself cause the resulting executable to be covered by
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* invalidate any other reasons why the executable file might be covered by
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* Copyright 2005, 2010 Develer S.r.l. (http://www.develer.com/)
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*
* \author Bernie Innocenti <bernie@codewiz.org>
* \author Francesco Sacchi <batt@develer.com>
* \author Luca Ottaviano <lottaviano@develer.com>
*
* \brief Low-level timer module for AVR MEGA (implementation).
*
* This module is automatically included so no need to include
* in test list.
* notest: avr
*/
#include <drv/timer_mega.h>
#include <cfg/macros.h> // BV()
#include <cpu/types.h>
#include <cpu/irq.h>
#include <avr/io.h>
#if CPU_AVR_ATMEGA1281 || CPU_AVR_ATMEGA1280 || CPU_AVR_ATMEGA168 || CPU_AVR_ATMEGA328P || CPU_AVR_ATMEGA2560
#define REG_TIFR0 TIFR0
#define REG_TIFR1 TIFR1
#define REG_TIFR2 TIFR2
#if CPU_AVR_ATMEGA1281 || CPU_AVR_ATMEGA1280 || CPU_AVR_ATMEGA2560
#define REG_TIFR3 TIFR3
#endif
#define REG_TIMSK0 TIMSK0
#define REG_TIMSK1 TIMSK1
#define REG_TIMSK2 TIMSK2
#if CPU_AVR_ATMEGA1281 || CPU_AVR_ATMEGA1280 || CPU_AVR_ATMEGA2560
#define REG_TIMSK3 TIMSK3
#endif
#define REG_TCCR0A TCCR0A
#define REG_TCCR0B TCCR0B
#define REG_TCCR2A TCCR2A
#define REG_TCCR2B TCCR2B
#define REG_OCR0A OCR0A
#define REG_OCR2A OCR2A
#define BIT_OCF0A OCF0A
#define BIT_OCF2A OCF2A
#define BIT_OCIE0A OCIE0A
#define BIT_OCIE2A OCIE2A
#else
#define REG_TIFR0 TIFR
#define REG_TIFR1 TIFR
#define REG_TIFR2 TIFR
#define REG_TIFR3 TIFR
#define REG_TIMSK0 TIMSK
#define REG_TIMSK1 TIMSK
#define REG_TIMSK2 TIMSK
#define REG_TIMSK3 ETIMSK
#define REG_TCCR0A TCCR0
#define REG_TCCR0B TCCR0
#define REG_TCCR2A TCCR2
#define REG_TCCR2B TCCR2
#define REG_OCR0A OCR0
#define REG_OCR2A OCR2
#define BIT_OCF0A OCF0
#define BIT_OCF2A OCF2
#define BIT_OCIE0A OCIE0
#define BIT_OCIE2A OCIE2
#endif
#if CPU_AVR_ATMEGA128 || CPU_AVR_ATMEGA64 || CPU_AVR_ATMEGA103
/* These ATMega have different prescaler options. */
#define TIMER0_PRESCALER_64 BV(CS02)
#define TIMER2_PRESCALER_64 (BV(CS21) | BV(CS20))
#else
#define TIMER0_PRESCALER_64 (BV(CS01) | BV(CS00))
#define TIMER2_PRESCALER_64 BV(CS22)
#endif
/** HW dependent timer initialization */
#if (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE0)
void timer_hw_init(void)
{
cpu_flags_t flags;
IRQ_SAVE_DISABLE(flags);
/* Reset Timer flags */
REG_TIFR0 = BV(BIT_OCF0A) | BV(TOV0);
/* Setup Timer/Counter interrupt */
REG_TCCR0A = 0; // TCCR2 reg could be separate or a unique register with both A & B values, this is needed to
REG_TCCR0B = 0;
REG_TCCR0A = BV(WGM01); /* Clear on Compare match */
#if TIMER_PRESCALER == 64
REG_TCCR0B |= TIMER0_PRESCALER_64;
#else
#error Unsupported value of TIMER_PRESCALER
#endif
TCNT0 = 0x00; /* Initialization of Timer/Counter */
REG_OCR0A = OCR_DIVISOR; /* Timer/Counter Output Compare Register */
/* Enable timer interrupts: Timer/Counter2 Output Compare (OCIE2) */
REG_TIMSK0 &= ~BV(TOIE0);
REG_TIMSK0 |= BV(BIT_OCIE0A);
IRQ_RESTORE(flags);
}
#elif (CONFIG_TIMER == TIMER_ON_OVERFLOW1)
void timer_hw_init(void)
{
cpu_flags_t flags;
IRQ_SAVE_DISABLE(flags);
/* Reset Timer overflow flag */
REG_TIFR1 |= BV(TOV1);
/* Fast PWM mode, 9 bit, 24 kHz, no prescaling. */
#if (TIMER_PRESCALER == 1) && (TIMER_HW_BITS == 9)
TCCR1A |= BV(WGM11);
TCCR1A &= ~BV(WGM10);
TCCR1B |= BV(WGM12) | BV(CS10);
TCCR1B &= ~(BV(WGM13) | BV(CS11) | BV(CS12));
/* Fast PWM mode, 8 bit, 24 kHz, no prescaling. */
#elif (TIMER_PRESCALER == 1) && (TIMER_HW_BITS == 8)
TCCR1A |= BV(WGM10);
TCCR1A &= ~BV(WGM11);
TCCR1B |= BV(WGM12) | BV(CS10);
TCCR1B &= ~(BV(WGM13) | BV(CS11) | BV(CS12));
#else
#error Unsupported value of TIMER_PRESCALER or TIMER_HW_BITS
#endif
TCNT1 = 0x00; /* initialization of Timer/Counter */
/* Enable timer interrupt: Timer/Counter1 Overflow */
REG_TIMSK1 |= BV(TOIE1);
IRQ_RESTORE(flags);
}
#elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE2)
void timer_hw_init(void)
{
cpu_flags_t flags;
IRQ_SAVE_DISABLE(flags);
/* Reset Timer flags */
REG_TIFR2 = BV(BIT_OCF2A) | BV(TOV2);
/* Setup Timer/Counter interrupt */
REG_TCCR2A = 0; // TCCR2 reg could be separate or a unique register with both A & B values, this is needed to
REG_TCCR2B = 0; // ensure correct initialization.
REG_TCCR2A = BV(WGM21);
#if TIMER_PRESCALER == 64
REG_TCCR2B |= TIMER2_PRESCALER_64;
#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 */
REG_OCR2A = (uint8_t)OCR_DIVISOR; /* Timer/Counter Output Compare Register */
/* Enable timer interrupts: Timer/Counter2 Output Compare (OCIE2) */
REG_TIMSK2 &= ~BV(TOIE2);
REG_TIMSK2 |= BV(BIT_OCIE2A);
IRQ_RESTORE(flags);
}
#elif (CONFIG_TIMER == TIMER_ON_OVERFLOW3)
#if CPU_AVR_ATMEGA168 || CPU_AVR_ATMEGA328P || CPU_AVR_ATMEGA32
#error For select target there is not TIMER_ON_OVERFLOW3, please select an other one.
#endif
void timer_hw_init(void)
{
cpu_flags_t flags;
IRQ_SAVE_DISABLE(flags);
/* Reset Timer overflow flag */
REG_TIFR3 |= BV(TOV3);
/* Fast PWM mode, 9 bit, 24 kHz, no prescaling. */
#if (TIMER_PRESCALER == 1) && (TIMER_HW_BITS == 9)
TCCR3A |= BV(WGM31);
TCCR3A &= ~BV(WGM30);
TCCR3B |= BV(WGM32) | BV(CS30);
TCCR3B &= ~(BV(WGM33) | BV(CS31) | BV(CS32));
/* Fast PWM mode, 8 bit, 24 kHz, no prescaling. */
#elif (TIMER_PRESCALER == 1) && (TIMER_HW_BITS == 8)
TCCR3A |= BV(WGM30);
TCCR3A &= ~BV(WGM31);
TCCR3B |= BV(WGM32) | BV(CS30);
TCCR3B &= ~(BV(WGM33) | BV(CS31) | BV(CS32));
#else
#error Unsupported value of TIMER_PRESCALER or TIMER_HW_BITS
#endif
/* initialization of Timer/Counter */
TCNT3 = 0x00;
/* Enable timer interrupt: Timer/Counter3 Overflow */
REG_TIMSK3 |= BV(TOIE3);
IRQ_RESTORE(flags);
}
#else
#error Unimplemented value for CONFIG_TIMER
#endif /* CONFIG_TIMER */