osd-contiki/cpu/avr/rtimer-arch.h
Ralf Schlatterbeck e88f60feee Make HW timer for contiki rtimer configurable
... and configure osd platform to use timer 5. With the new
configuration we can use timer 3 for generating hardware PWM.
2014-05-31 16:17:07 +02:00

103 lines
4.1 KiB
C

/*
* Copyright (c) 2007, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
*/
#ifndef RTIMER_ARCH_H_
#define RTIMER_ARCH_H_
#include <avr/interrupt.h>
/* Nominal ARCH_SECOND is F_CPU/prescaler, e.g. 8000000/1024 = 7812
* Other prescaler values (1, 8, 64, 256) will give greater precision
* with shorter maximum intervals.
* Setting RTIMER_ARCH_PRESCALER to 0 will leave Timers alone.
* rtimer_arch_now() will then return 0, likely hanging the cpu if used.
* Timer1 is used if Timer3 is not available.
*
* Note the rtimer tick to clock tick conversion will be nominally correct only
* when the same oscillator is used for both clocks.
* When an external 32768 watch crystal is used for clock ticks my raven CPU
* oscillator is 1% slow, 32768 counts on crystal = ~7738 rtimer ticks.
* For more accuracy define F_CPU to 0x800000 and optionally phase lock CPU
* clock to 32768 crystal. This gives RTIMER_ARCH_SECOND = 8192.
*/
#ifndef RTIMER_ARCH_PRESCALER
#define RTIMER_ARCH_PRESCALER 1024UL
#endif
#if RTIMER_ARCH_PRESCALER
#define RTIMER_ARCH_SECOND (F_CPU/RTIMER_ARCH_PRESCALER)
#else
#define RTIMER_ARCH_SECOND 0
#endif
#ifndef PLAT_TIMER
/* By default use timer 3 if available. Fall back to timer1 if not. */
#ifdef TCNT3
#define PLAT_TIMER 3
#else
#define PLAT_TIMER 1
#endif /* TCNT3 */
#endif /* !PLAT_TIMER */
#define _R_CONC_(_x,_y,_z) _x##_y##_z
#define _C_R_CONC_(_X,_Y,_Z) _R_CONC_(_X,_Y,_Z)
#define PLAT_ICF _C_R_CONC_(ICF,PLAT_TIMER,)
#define PLAT_ICIE _C_R_CONC_(ICIE,PLAT_TIMER,)
#define PLAT_OCFA _C_R_CONC_(OCF,PLAT_TIMER,A)
#define PLAT_OCFB _C_R_CONC_(OCF,PLAT_TIMER,B)
#define PLAT_OCFC _C_R_CONC_(OCF,PLAT_TIMER,C)
#define PLAT_OCIEA _C_R_CONC_(OCIE,PLAT_TIMER,A)
#define PLAT_OCIEB _C_R_CONC_(OCIE,PLAT_TIMER,B)
#define PLAT_OCIEC _C_R_CONC_(OCIE,PLAT_TIMER,C)
#define PLAT_OCRA _C_R_CONC_(OCR,PLAT_TIMER,A)
#define PLAT_TCCRA _C_R_CONC_(TCCR,PLAT_TIMER,A)
#define PLAT_TCCRB _C_R_CONC_(TCCR,PLAT_TIMER,B)
#define PLAT_TCCRC _C_R_CONC_(TCCR,PLAT_TIMER,C)
#define PLAT_TCNT _C_R_CONC_(TCNT,PLAT_TIMER,)
#define PLAT_TIFR _C_R_CONC_(TIFR,PLAT_TIMER,)
#define PLAT_TIMSK _C_R_CONC_(TIMSK,PLAT_TIMER,)
#define PLAT_TOIE _C_R_CONC_(TOIE,PLAT_TIMER,)
#define PLAT_TOV _C_R_CONC_(TOV,PLAT_TIMER,)
#define PLAT_VECT _C_R_CONC_(TIMER,PLAT_TIMER,_COMPA_vect)
#if RTIMER_ARCH_PRESCALER
#define rtimer_arch_now() (PLAT_TCNT)
#else
#define rtimer_arch_now() (0)
#endif
/* some platforms don't have OCIEXC, we rely on the processor
* definition to #define OCIEXC OCIEXB in that case. This won't hurt
* since OCIEXC isn't used anyway.
*/
void rtimer_arch_sleep(rtimer_clock_t howlong);
#endif /* RTIMER_ARCH_H_ */