Make sure the timer wraps around correctly independent of the os tick frequency
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					 1 changed files with 29 additions and 15 deletions
				
			
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			@ -2,26 +2,40 @@
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#include "timer.h"
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void timer_init(void) {}
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static systime_t last_systime = 0;
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static systime_t overflow = 0;
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static uint32_t current_time_ms = 0;
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void timer_clear(void) {}
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uint16_t timer_read(void)
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{
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    return (uint16_t)ST2MS(chVTGetSystemTime());
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void timer_init(void) {
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  timer_clear();
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}
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uint32_t timer_read32(void)
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{
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    return ST2MS(chVTGetSystemTime());
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void timer_clear(void) {
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  last_systime = chVTGetSystemTime();
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  overflow = 0;
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  current_time_ms = 0;
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}
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uint16_t timer_elapsed(uint16_t last)
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{
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    return (uint16_t)(ST2MS(chVTTimeElapsedSinceX(MS2ST(last))));
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uint16_t timer_read(void) {
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  return (uint16_t)timer_read32();
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}
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uint32_t timer_elapsed32(uint32_t last)
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{
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    return ST2MS(chVTTimeElapsedSinceX(MS2ST(last)));
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uint32_t timer_read32(void) {
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  // Note: We assume that the timer update is called at least once betweeen every wrap around of the system time
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  systime_t current_systime = chVTGetSystemTime();
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  systime_t elapsed = current_systime - last_systime + overflow;
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  uint32_t elapsed_ms = ST2MS(elapsed);
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  current_time_ms += elapsed_ms;
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  overflow = elapsed - MS2ST(elapsed_ms);
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  last_systime = current_systime;
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  return current_time_ms;
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}
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uint16_t timer_elapsed(uint16_t last) {
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  return timer_read() - last;
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}
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uint32_t timer_elapsed32(uint32_t last) {
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  return timer_read32() - last;
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}
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