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is sceRtcGetTickResolution a constant?

 
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jonny



Joined: 22 Sep 2005
Posts: 351

PostPosted: Fri Jan 27, 2006 2:25 am    Post subject: is sceRtcGetTickResolution a constant? Reply with quote

as the subject says, can i assume this?

thanks
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Raphael



Joined: 17 Jan 2006
Posts: 646
Location: Germany

PostPosted: Fri Jan 27, 2006 3:16 am    Post subject: Reply with quote

It shoul be, since the time generation is based on these ticks, so if the ticks per second weren't constant, you'd get jumps in times.
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PacManFan



Joined: 25 Jun 2005
Posts: 66

PostPosted: Fri Jan 27, 2006 3:36 am    Post subject: Reply with quote

I'm not sure of this, but I think it's based on the clock frequency. You might want to run a few tests to see what it is at 166, 266, and 333. Then you can generate your own constants. If you find out what they are offhand, please post them here.

-PMF
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Raphael



Joined: 17 Jan 2006
Posts: 646
Location: Germany

PostPosted: Fri Jan 27, 2006 4:00 am    Post subject: Reply with quote

Well, that's what I was implicitly expecting, but should have mentionend. It's constant under a specific clock frequency.
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chp



Joined: 23 Jun 2004
Posts: 313

PostPosted: Fri Jan 27, 2006 4:18 am    Post subject: Reply with quote

When I looked at sceRtcGetTickResolution(), it was something like 1000000, which sounds like an oddly round number for 222Mhz. I suspect that if the timer is cycle-based, the RTC compensates this in its calculations.
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bulb



Joined: 19 Jan 2006
Posts: 50

PostPosted: Fri Jan 27, 2006 4:30 am    Post subject: Reply with quote

My guess is tick resolution should be independent of CPU clock (always the same). Modifing CPU clock only means that some tasks will use more or less cycles, it has nothing to do with resolution. The same is true for Pentium CPUs anyway.
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jonny



Joined: 22 Sep 2005
Posts: 351

PostPosted: Fri Jan 27, 2006 6:21 am    Post subject: Reply with quote

seems fixed to 1000000
( i'd bet i have seen it at 1500000 some time ago :S , but i can be wrong here)
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