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Diffstat (limited to 'wirish/wirish_time.h')
-rw-r--r-- | wirish/wirish_time.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/wirish/wirish_time.h b/wirish/wirish_time.h new file mode 100644 index 0000000..a0c0c82 --- /dev/null +++ b/wirish/wirish_time.h @@ -0,0 +1,99 @@ +/****************************************************************************** + * The MIT License + * + * Copyright (c) 2010 Perry Hung. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + *****************************************************************************/ + +/** + * @file time.h + * @brief Timing and delay functions. + */ + +#ifndef _TIME_H +#define _TIME_H + +#include "libmaple.h" +#include "nvic.h" +#include "systick.h" +#include "boards.h" + +#define US_PER_MS 1000 + +/** + * Returns time (in milliseconds) since the beginning of program + * execution. On overflow, restarts at 0. + * @see micros() + */ +static inline uint32 millis(void) { + return systick_timer_millis; +} + +/** + * Returns time (in microseconds) since the beginning of program + * execution. On overflow, restarts at 0. + * @see millis() + */ +static inline uint32 micros(void) { + uint32 ms; + uint32 cycle_cnt; + uint32 res; + + nvic_globalirq_disable(); + + cycle_cnt = systick_get_count(); + ms = millis(); + + nvic_globalirq_enable(); + + /* SYSTICK_RELOAD_VAL is 1 less than the number of cycles it + actually takes to complete a SysTick reload */ + res = (ms * US_PER_MS) + + (SYSTICK_RELOAD_VAL + 1 - cycle_cnt)/CYCLES_PER_MICROSECOND; + + return res; +} + +/** + * Delay for at least the given number of milliseconds. + * + * Interrupts, etc. may cause the actual number of milliseconds to + * exceed ms. However, this function will return no less than ms + * milliseconds from the time it is called. + * + * @param ms the number of milliseconds to delay. + * @see delayMicroseconds() + */ +void delay(unsigned long ms); + +/** + * Delay for at least the given number of microseconds. + * + * Interrupts, etc. may cause the actual number of microseconds to + * exceed us. However, this function will return no less than us + * microseconds from the time it is called. + * + * @param us the number of microseconds to delay. + * @see delay() + */ +void delayMicroseconds(uint32 us); + +#endif + |