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Diffstat (limited to 'wirish/time.c')
-rw-r--r-- | wirish/time.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/wirish/time.c b/wirish/time.c new file mode 100644 index 0000000..69e962c --- /dev/null +++ b/wirish/time.c @@ -0,0 +1,77 @@ +/* ***************************************************************************** + * 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.c + * + * @brief + */ + +#include "libmaple.h" +#include "systick.h" +#include "time.h" + +#define CYCLES_PER_MICROSECOND 72 +#define FUDGE 42 + +extern volatile uint32 systick_timer_millis; + +uint32 millis() { + unsigned long m; + m = systick_timer_millis; + return m; +} + +void delay(unsigned long ms) +{ + unsigned long start = millis(); + + while (millis() - start <= ms) + ; +} + + + +#if 1 +void delayMicroseconds(uint32 us) { + uint32 target; + uint32 last, cur, count; + /* fudge factor hacky hack hack for function overhead */ + target = us * CYCLES_PER_MICROSECOND - FUDGE; + + /* Get current count */ + last = systick_get_count(); + cur = systick_get_count(); + count = last; + while ((count-cur) <= target) { + cur = systick_get_count(); + + /* check for overflow */ + if (cur > last) { + count += MAPLE_RELOAD_VAL; + } + last = cur; + } +} +#endif |