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author | Joel Challis <git@zvecr.com> | 2021-11-19 18:41:02 +0000 |
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committer | GitHub <noreply@github.com> | 2021-11-19 10:41:02 -0800 |
commit | 2728603fe6d73e805a539d337fd01051c46ca806 (patch) | |
tree | 5c83ffc7efa112da870bd5d8502a9d91d4792f35 /platforms/avr/timer.c | |
parent | 43b9e23bae12916d5161f03700c9bfe46737324b (diff) | |
download | qmk_firmware-2728603fe6d73e805a539d337fd01051c46ca806.tar.gz qmk_firmware-2728603fe6d73e805a539d337fd01051c46ca806.zip |
Move tmk_core/common/<plat> (#13918)
Diffstat (limited to 'platforms/avr/timer.c')
-rw-r--r-- | platforms/avr/timer.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/platforms/avr/timer.c b/platforms/avr/timer.c new file mode 100644 index 0000000000..c2e6c6e081 --- /dev/null +++ b/platforms/avr/timer.c @@ -0,0 +1,133 @@ +/* +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/>. +*/ + +#include <avr/io.h> +#include <avr/interrupt.h> +#include <util/atomic.h> +#include <stdint.h> +#include "timer_avr.h" +#include "timer.h" + +// counter resolution 1ms +// NOTE: union { uint32_t timer32; struct { uint16_t dummy; uint16_t timer16; }} +volatile uint32_t timer_count; + +/** \brief timer initialization + * + * FIXME: needs doc + */ +void timer_init(void) { +#if TIMER_PRESCALER == 1 + uint8_t prescaler = _BV(CS00); +#elif TIMER_PRESCALER == 8 + uint8_t prescaler = _BV(CS01); +#elif TIMER_PRESCALER == 64 + uint8_t prescaler = _BV(CS00) | _BV(CS01); +#elif TIMER_PRESCALER == 256 + uint8_t prescaler = _BV(CS02); +#elif TIMER_PRESCALER == 1024 + uint8_t prescaler = _BV(CS00) | _BV(CS02); +#else +# error "Timer prescaler value is not valid" +#endif + +#if defined(__AVR_ATmega32A__) + // Timer0 CTC mode + TCCR0 = _BV(WGM01) | prescaler; + + OCR0 = TIMER_RAW_TOP; + TIMSK = _BV(OCIE0); +#elif defined(__AVR_ATtiny85__) + // Timer0 CTC mode + TCCR0A = _BV(WGM01); + TCCR0B = prescaler; + + OCR0A = TIMER_RAW_TOP; + TIMSK = _BV(OCIE0A); +#else + // Timer0 CTC mode + TCCR0A = _BV(WGM01); + TCCR0B = prescaler; + + OCR0A = TIMER_RAW_TOP; + TIMSK0 = _BV(OCIE0A); +#endif +} + +/** \brief timer clear + * + * FIXME: needs doc + */ +inline void timer_clear(void) { + ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { timer_count = 0; } +} + +/** \brief timer read + * + * FIXME: needs doc + */ +inline uint16_t timer_read(void) { + uint32_t t; + + ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { t = timer_count; } + + return (t & 0xFFFF); +} + +/** \brief timer read32 + * + * FIXME: needs doc + */ +inline uint32_t timer_read32(void) { + uint32_t t; + + ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { t = timer_count; } + + return t; +} + +/** \brief timer elapsed + * + * FIXME: needs doc + */ +inline uint16_t timer_elapsed(uint16_t last) { + uint32_t t; + + ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { t = timer_count; } + + return TIMER_DIFF_16((t & 0xFFFF), last); +} + +/** \brief timer elapsed32 + * + * FIXME: needs doc + */ +inline uint32_t timer_elapsed32(uint32_t last) { + uint32_t t; + + ATOMIC_BLOCK(ATOMIC_RESTORESTATE) { t = timer_count; } + + return TIMER_DIFF_32(t, last); +} + +// excecuted once per 1ms.(excess for just timer count?) +#ifndef __AVR_ATmega32A__ +# define TIMER_INTERRUPT_VECTOR TIMER0_COMPA_vect +#else +# define TIMER_INTERRUPT_VECTOR TIMER0_COMP_vect +#endif +ISR(TIMER_INTERRUPT_VECTOR, ISR_NOBLOCK) { timer_count++; } |