Rockwell Automation 2711P Software Development Kit User Manual - Manual (Page 51)

Publication 2711P-UM005A-EN-P - March 2007
PanelView Plus CE-Specific Extensions to the WinCE API 51
pdwFrequency
Pointer to an application allocated DWORD containing the frequency
(in Hz) to which the timer is to be set.
When the function is successful, it changes *Frequency to the actual
value used. The *Frequency may differ from the initial value due to
resolution issues in the hardware timer. Valid values range from 1 –
20,000 HZ for the Critical Timer and 1 – 1,000 HZ for the non-Critical
Timers.
Return Values:
Remarks:
Applications must check the frequency returned and use it in their
counter calculations. The frequency cannot be set once the timer has
been started.
Portability:
This function is specific to the PanelView Plus CE or the RAC6182.
Requirements:
UserTimerRequestFrequency - Return Codes
Value Description
USER_TIMER_OK The timer has been set to the closest possible
frequency, and the actual frequency used is
returned at pdwFrequency
USER_TIMER_INVALID_TIMER The timer number is not valid for the system.
USER_TIMER_INVALID_PARAMETER The requested frequency is NULL or out of range.
USER_TIMER_NOT_CLAIMED This application has not claimed this timer.
Runs On Version Defined In Link To
PanelView Plus CE
RAC6182
All usertimers.h usertimers.lib