text: #ifndef __TIMER_H__
  #define __TIMER_H__
  
  typedef struct {
  	unsigned elapsed;
  	unsigned timeout;
  	bool triggered;
  	bool enabled;
  } sys_timer;
  
  void   sys_timer_reset(sys_timer *timer);
  void   sys_timer_enable(sys_timer *timer, bool enabled);
  void   sys_timer_set(sys_timer *timer, UINT32 microseconds);
  void   sys_timer_run(sys_timer *timer, UINT32 microseconds);
  bool   sys_timer_is_triggered(sys_timer *timer);
  bool   sys_timer_is_enabled(sys_timer *timer);
  void   sys_timer_clear(sys_timer *timer);
  UINT32 sys_timer_elapsed(sys_timer *timer);
  
  #endif
  