Rockwell Automation 6182 SDK - Manual (Page 76)

4–36 RAC6182-Specific Extensions to the CE API
Publication 6182-UM002B-EN-P
Applications must check the *Frequency returned and use it in their
counter calculations.
Note: As of this writing, RAC6182 user timers operate at a fixed
frequency of 75MHz. Thus, attempts to adjust the timers to
frequencies other than 75MHz will not be effective.
However, the timers’ frequencies may become adjustable in
future releases of the RAC6182, and no guarantee can be
made that the timers will always have a fundamental
frequency of 75MHz.
ATTENTION: This function has unpredictable results if
called when the timer is running.
Parameter Description
TimerNumber Number of a timer previously claimed.
Frequency 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.
Return Value
Possible return values are represented by macros defined in usertimers.h:
USER_TIMER_OK - Successfully claimed or released timer
USER_TIMER_INVALID_TIMER - Timer number not present on
system
USER_TIMER_NOT_CLAIMED - Another application already has
claimed the timer so this application could not claim it
USER_TIMER_INVALID_PARAMETER - Invalid value
Portability
This function is specific to the RAC6182 hardware.
See Also
UserTimerClaim and UserTimerSet