OAL_TIMER_STATE (Windows Embedded CE 6.0)

1/5/2010

This structure stores information about the timer module component control block. It unites all internal module variables that can be used by other OAL modules.

Syntax

typedef struct {
  UINT32 countsPerMSec;
  UINT32 countsMargin;
  UINT32 maxPeriodMSec;
  UINT32 msecPerSysTick;
  UINT32 countsPerSysTick;
  UINT32 actualMSecPerSysTick;
  UINT32 actualCountsPerSysTick;
  volatile UINT64 curCounts;
} OAL_TIMER_STATE, *POAL_TIMER_STATE;

Members

• countsPerMSec
  Specifies the input clock frequency in kHz, which is the number of input clock ticks that fit in the 1 ms time frame.

• countsMargin
  Defines the number of ticks that must elapse before the timer interrupt can safely change the timer value. This member is used as a parameter for functions that manipulate the timer such as OEMIdle and pOEMUpdateRescheduleTime.

• maxPeriodMSec
  Specifies the maximum timer period supported by the hardware, in ms. Some modules, such as the profiler and ILT, change this value to reduce the maximum time between system timer interrupts.

• msecPerSysTick
  Defines a base timer period value representing the number of ms per system tick.

• countsPerSysTick
  Defines a base timer period value representing the counts per system tick. This value must always equal msecPerSysTick * countsPerMSec.

• actualMSecPerSysTick
  Timer period value representing actual ms per system tick. The interrupt handler must use this actual value to update the system counter CurMSec.

• actualCountsPerSysTick
  Timer period value representing the actual counts per system tick. The interrupt handler must use this actual value to update system counter curCounts.

• curCounts
  Counts at the last system tick.

Remarks

At the beginning of a period, the handler must restore the actual values from the base variables. This is equivalent to msecPerSysTick / countsPerSysTick.

Requirements

See Also

Reference

Timer Structures