OpenModem/bertos/cpu/avr/drv/timer_xmega.h

135 lines
4.8 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
* the Free Software Foundation; either version 2 of the License, or
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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
*
* As a special exception, you may use this file as part of a free software
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* templates or use macros or inline functions from this file, or you compile
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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
* the GNU General Public License.
*
* Copyright 2003, 2004, 2005, 2010 Develer S.r.l. (http://www.develer.com/)
* Copyright 2000 Bernie Innocenti <bernie@codewiz.org>
* Copyright 2011 Onno <developer@gorgoz.org>
*
* -->
*
* \brief Low-level timer module for AVR XMEGA (interface).
*
* This file is heavily inspired by the AVR implementation for BeRTOS,
* but uses a different approach for implementing the different debug
* ports, by using the timer structs.
*
* \author Onno <developer@gorgoz.org>
*
*/
#ifndef DRV_TIMER_XMEGA_H
#define DRV_TIMER_XMEGA_H
#include <hw/hw_cpufreq.h> /* CPU_FREQ */
#include "cfg/cfg_timer.h" /* CONFIG_TIMER */
#include <cfg/compiler.h> /* uint8_t */
#include <cfg/macros.h> /* DIV_ROUND */
#include <avr/io.h>
#include <avr/interrupt.h>
/*
* \name Values for CONFIG_TIMER.
*
* Select which hardware timer interrupt to use for system clock and softtimers.
* $WIZ$ timer_select = "TIMER_USE_TCC0", "TIMER_USE_TCC1", "TIMER_USE_TCD0", "TIMER_USE_TCE0", "TIMER_USE_TCD1", "TIMER_DEFAULT"
*/
#define TIMER_USE_TCC0 1
#define TIMER_USE_TCC1 2
#define TIMER_USE_TCD0 3
#define TIMER_USE_TCE0 4
// The XMEGA A Family has one extra timer
#ifdef CPU_AVR_XMEGA_A
#define TIMER_USE_TCD1 5
#endif
#define TIMER_DEFAULT TIMER_USE_TCC1 ///< Default system timer
/*
* Hardware dependent timer initialization.
*/
#if (CONFIG_TIMER == TIMER_USE_TCC0)
#define TIMER_OVF_VECT TCC0_OVF_vect
#define TIMERCOUNTER TCC0
#elif (CONFIG_TIMER == TIMER_USE_TCC1)
#define TIMER_OVF_VECT TCC1_OVF_vect
#define TIMERCOUNTER TCC1
#elif (CONFIG_TIMER == TIMER_USE_TCD0)
#define TIMER_OVF_VECT TCD0_OVF_vect
#define TIMERCOUNTER TCD0
#elif (CONFIG_TIMER == TIMER_USE_TCE0)
#define TIMER_OVF_VECT TCE0_OVF_vect
#define TIMERCOUNTER TCE0
#elif (CONFIG_TIMER == TIMER_USE_TCD1)
#define TIMER_OVF_VECT TCD1_OVF_vect
#define TIMERCOUNTER TCD1
#else
#error Unimplemented value for CONFIG_TIMER
#endif /* CONFIG_TIMER */
//define the Interrupt Service Routine for this Timer Mode
#define DEFINE_TIMER_ISR DECLARE_ISR_CONTEXT_SWITCH(TIMER_OVF_VECT)
//define the Ticks per second we want
#define TIMER_TICKS_PER_SEC 1000
//define the Prescaler to use, which is dependend on the amount
//of ticks per second, the maximum value for the TOP value of the
//timer (0xFFFF) and the clock frequency.
//The maximum clock frequency is 32Mhz, so as long as the TIMER_TICKS_PER_SEC
//is larger then (about) 500 no prescaler is required.
#define TIMER_PRESCALER 1
//define the TOP/PERIOD value
#define TIMER_PERIOD_VALUE DIV_ROUND(DIV_ROUND(CPU_FREQ, TIMER_PRESCALER), TIMER_TICKS_PER_SEC)
//check if the TIMER_PRESCALER is large enough to accomate for the TIMER_TICKS_PER_SEC
#if TIMER_PERIOD_VALUE > 0xFFFF
#error Timer cannot generate the required Ticks per second, please adjust TIMER_PRESCALER
#endif
//define TIMER_HW_CNT it is used by the timer.c module to determine the 'edge' of the hardware counter
#define TIMER_HW_CNT TIMER_PERIOD_VALUE
/** Frequency of the hardware high precision timer. */
#define TIMER_HW_HPTICKS_PER_SEC DIV_ROUND(CPU_FREQ, TIMER_PRESCALER)
// Type of time expressed in ticks of the hardware high-precision timer
typedef uint16_t hptime_t;
#define SIZEOF_HPTIME_T 2
INLINE hptime_t timer_hw_hpread(void)
{
return (TIMERCOUNTER).CNT;
}
/* Not needed, IRQ timer flag cleared automatically */
#define timer_hw_irq() do {} while (0)
/* Not needed, timer IRQ handler called only for timer source */
#define timer_hw_triggered() (true)
void timer_hw_init(void);
#endif /* DRV_TIMER_XMEGA_H */