DosTmrQueryFreq
Provides the frequency of the IRQ0 high resolution timer (Intel 8254) / Queries the performance timer for its frequency.
Syntax
DosTmrQueryFreq (pulTmrFreq)
Parameters
- pulTmrFreq (PULONG) - output
- Timer Frequency.
- Provides the frequency of the IRQ0 high resolution timer in hertz (timer units/sec).
Return Code
- rc (APIRET) - returns
- DosTmrQueryFrequency returns the following values:
- 0 NO_ERROR
- 87 ERROR_INVALID_PARAMETER
- 535 ERROR_TMR_NO_DEVICE
- 99 ERROR_DEVICE_IN_USE
Remarks
Currently, the timer frequency = 1.19318 Mhz, for a timer resolution of about .838 microseconds. (See also DosTmrQueryTime.)
Example Code
#define INCL_DOSPROFILE #include <os2.h> PULONG pulTmrFreq; /* Timer Frequency. */ APIRET rc; /* Return Code. */ rc = DosTmrQueryFreq(pulTmrFreq);