keychron_qmk_firmware/common/avr/timer_avr.h
2014-07-30 14:07:43 +09:00

43 lines
1.2 KiB
C

/*
Copyright 2011 Jun Wako <wakojun@gmail.com>
This program 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
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef TIMER_AVR_H
#define TIMER_AVR_H 1
#include <stdint.h>
#ifndef TIMER_PRESCALER
# if F_CPU > 16000000
# define TIMER_PRESCALER 256
# elif F_CPU > 2000000
# define TIMER_PRESCALER 64
# elif F_CPU > 250000
# define TIMER_PRESCALER 8
# else
# define TIMER_PRESCALER 1
# endif
#endif
#define TIMER_RAW_FREQ (F_CPU/TIMER_PRESCALER)
#define TIMER_RAW TCNT0
#define TIMER_RAW_TOP (TIMER_RAW_FREQ/1000)
#if (TIMER_RAW_TOP > 255)
# error "Timer0 can't count 1ms at this clock freq. Use larger prescaler."
#endif
#endif