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| author | Marti Bolivar <mbolivar@leaflabs.com> | 2012-06-27 14:04:10 -0400 |
|---|---|---|
| committer | Marti Bolivar <mbolivar@leaflabs.com> | 2012-06-27 14:04:10 -0400 |
| commit | 0e7a40c7b790f13daec1b8a73f20d1dda57134f9 (patch) | |
| tree | b4d16f74946dd73d55baf1436448f65ea8b35d91 /wirish | |
| parent | 1ea491a3ed723b9895d2827deb235fdace870ea4 (diff) | |
| download | librambutan-0e7a40c7b790f13daec1b8a73f20d1dda57134f9.tar.gz librambutan-0e7a40c7b790f13daec1b8a73f20d1dda57134f9.zip | |
Clean up micros().
Don't leave US_PER_MS user-visible. Remove an unnecessary variable.
Signed-off-by: Marti Bolivar <mbolivar@leaflabs.com>
Diffstat (limited to 'wirish')
| -rw-r--r-- | wirish/include/wirish/wirish_time.h | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/wirish/include/wirish/wirish_time.h b/wirish/include/wirish/wirish_time.h index 1520b1e..eb6c68f 100644 --- a/wirish/include/wirish/wirish_time.h +++ b/wirish/include/wirish/wirish_time.h @@ -37,8 +37,6 @@ #include <wirish/boards.h> -#define US_PER_MS 1000 - /** * Returns time (in milliseconds) since the beginning of program * execution. On overflow, restarts at 0. @@ -56,19 +54,18 @@ static inline uint32 millis(void) { static inline uint32 micros(void) { uint32 ms; uint32 cycle_cnt; - uint32 res; do { ms = millis(); cycle_cnt = systick_get_count(); } while (ms != millis()); +#define US_PER_MS 1000 /* 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; + return ((ms * US_PER_MS) + + (SYSTICK_RELOAD_VAL + 1 - cycle_cnt) / CYCLES_PER_MICROSECOND); +#undef US_PER_MS } /** |