common/mbed/timer.c

   1 #include "cmsis.h"
   2 #include "timer.h"
   3
   4 /* Mill second tick count */
   5 volatile uint32_t timer_count = 0;
   6
   7 /* Timer interrupt handler */
   8 void SysTick_Handler(void)  {
   9     timer_count++;
  10 }
  11
  12 void timer_init(void)
  13 {
  14     timer_count = 0;
  15     SysTick_Config(SystemCoreClock / 1000); /* 1ms tick */
  16 }
  17
  18 void timer_clear(void)
  19 {
  20     timer_count = 0;
  21 }
  22
  23 uint16_t timer_read(void)
  24 {
  25     return (uint16_t)(timer_count & 0xFFFF);
  26 }
  27
  28 uint32_t timer_read32(void)
  29 {
  30     return timer_count;
  31 }
  32
  33 uint16_t timer_elapsed(uint16_t last)
  34 {
  35     return TIMER_DIFF_16(timer_read(), last);
  36 }
  37
  38 uint32_t timer_elapsed32(uint32_t last)
  39 {
  40     return TIMER_DIFF_32(timer_read32(), last);
  41 }