[an error occurred while processing this directive] [an error occurred while processing this directive][an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive] (none) [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive][an error occurred while processing this directive] [an error occurred while processing this directive][an error occurred while processing this directive] [an error occurred while processing this directive][an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive] (none) [an error occurred while processing this directive] [an error occurred while processing this directive] [an error occurred while processing this directive][an error occurred while processing this directive]
 
[an error occurred while processing this directive] [an error occurred while processing this directive]
Skåne Sjælland Linux User Group - http://www.sslug.dk Home   Subscribe   Mail Archive   Forum   Calendar   Search
MhonArc Date: [Date Prev] [Date Index] [Date Next]   Thread: [Date Prev] [Thread Index] [Date Next]   MhonArc
 

Re: [CPROG] Måling af tid på mindre end 1 sekund.



Poul-Erik Andreasen <sslug@sslug> writes:

> Det du opgiver her er alt sammen opløsninger, men det siger jo ikke
> noget om præcision. 

Korrekt.

Det er noget siden jeg kiggede paa noget saadant, og har derfor ikke
denne information.

Med hensyn til TSC, saa boer praecissionen vaere specificeret af
Intel, da det er en Pentium specifik feature.

PIT vil jeg _gaette_ paa kan vaere af forskellig praecission alt efter
hvilket chipset der anvendes.  Jeg aner ikke om der er en standard for
minimum PIT praecission.

ACPI timer er jeg helt paa bar bund med, men mon ikke ACPI
specifikationen siger noget om praecission?  Et hurtigt kig med Google
gav foelgende:

  The ACPI specification requires a power management timer that
  provides   an accurate time value used by system software [.... ]
  The power management timer is a 24-bit or 32-bit fixed rate free
  running count-up timer that runs off a 3.579545 MHz clock.

Ikke noget om hvad praecissionen af klokken skal vaere, men med en
krystal tror jeg ikke det er det du skal bekymre dig om.  Praecission
vil nok primaert afhaenge af den tid det tager at aflaese samt resette
timeren.

Men hvad er dine krav egentlig?

/Esben
-- 
In the beginning was the word. And the word was "Aardvark".


 
Home   Subscribe   Mail Archive   Index   Calendar   Search

 
 
Questions about the web-pages to <www_admin>. Last modified 2005-08-10, 20:09 CEST [an error occurred while processing this directive]
This page is maintained by [an error occurred while processing this directive]MHonArc [an error occurred while processing this directive] # [an error occurred while processing this directive] *