Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 28 Jan 2008 10:59:50 -0800
From:      Sam Leffler <sam@errno.com>
To:        Sean Bruno <sbruno@miralink.com>
Cc:        freebsd-hackers@freebsd.org
Subject:   Re: How long is a hz?
Message-ID:  <479E2626.6040207@errno.com>
In-Reply-To: <479E24A1.60103@miralink.com>
References:  <479E0A1C.2060908@miralink.com>	<20080128134253.C1539@mail.tacorp.net> <479E24A1.60103@miralink.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Sean Bruno wrote:
> Jason Slagle wrote:
>> On Mon, 28 Jan 2008, Sean Bruno wrote:
>>
>>> I couldn't quite find the definition for "hz" in sys/ this morning.  
>>> What is it's value and where is it defined?
>>
>> From http://en.wikipedia.org/wiki/Hertz
>>
>>    The hertz (symbol: Hz) is the International System of Units (SI) base
>>    unit of frequency. Its base unit is cycle/s or s^-1 (also called
>>    inverse seconds, reciprocal seconds). In English, hertz is used as 
>> both
>>    singular and plural. As any SI unit, Hz can be prefixed; commonly 
>> used
>>    multiples are kHz (kilohertz, 10^3 Hz), MHz (megahertz, 10^6 Hz), GHz
>>    (gigahertz, 10^9 Hz) and THz (terahertz, 10^12 Hz).
>>
>>    One hertz simply means one cycle per second (typically that which is
>>    being counted is a complete cycle); 100 Hz means one hundred 
>> cycles per
>>    second, and so on. The unit may be applied to any periodic event--for
>>    example, a clock might be said to tick at 1 Hz, or a human heart 
>> might
>>    be said to beat at 1.2 Hz. The frequencies of aperiodic events, 
>> such as
>>    radioactive decay, are expressed in becquerels.
>>
>>
> But more importantly, where is "hz" defined in the kernel tree?
>
> Sean
> _______________________________________________
> freebsd-hackers@freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-hackers
> To unsubscribe, send any mail to 
> "freebsd-hackers-unsubscribe@freebsd.org"
>
>
http://fxr.watson.org/fxr/ident?i=hz



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?479E2626.6040207>