C/C++ in Embedded Chronographs
By William Smith, April 01, 2004
William examines the use of C/C++ for real-time event timing, then presents a generic system that supports Standard C/C++ on Windows and Palm platforms.
April 04:
Listing 1: clock.hpp.
// clock.hpp Begin
#ifdef __PALMOS
#include <SystemMgr.h>
#include <TimeMgr.h>
#define CLOCKS_PER_SEC ((clock_t)SysTicksPerSecond())
typedef long clock_t;
#elif defined( __WINDOWS )
#include <windows.h>
#define CLOCKS_PER_SEC 1000
typedef long clock_t;
#else
#include <time.h>
#endif
class cClock
{
public:
cClock( clock_t ClocksPerSec = CLOCKS_PER_SEC );
cClock( clock_t CalPeriod, clock_t CalError,
clock_t ClocksPerSec = CLOCKS_PER_SEC );
~cClock() {};
clock_t StartClock();
clock_t GetClock();
clock_t GetCalClock();
clock_t GetClocksPerSec();
static void SetCalibration( clock_t CalPeriod, clock_t CalCorrection );
static void CalcCalibration( clock_t ActualTime,
clock_t MeasuredTime, clock_t Correction );
private:
static clock_t _mClockStart;
static clock_t _mNumClockCalls;
static clock_t _mDesClockRes;
static clock_t _mDesClocksPerSec;
static clock_t _mNatClockRes;
static clock_t _mCalPeriod;
static clock_t _mCalCorrection;
static void InitClock();
static inline clock_t LoopClock( clock_t Clock1, clock_t *NumCalls );
static void SetClockRes( clock_t ClocksPerSec );
static clock_t RoundToRes( clock_t Clock );
};
// clock.hpp End
