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Date: Thu, 5 Jul 2001 13:43:06 +0400
From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
To: "Oleg I. Vdovikin" <vdovikin@jscc.ru>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [patch] Re: alpha - generic_init_pit - why using RTC for calibration?
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In-Reply-To: <003e01c10522$1c9cf580$4d28d0c3@jscc.ru>; from vdovikin@jscc.ru on Thu, Jul 05, 2001 at 11:14:19AM +0400
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On Thu, Jul 05, 2001 at 11:14:19AM +0400, Oleg I. Vdovikin wrote:
>     Richard, thanks. But please use calibrate_cc version which I've submited
> as a patch - it gives more accuracy with maximum latch we can ever use and

With both variants even on a 166MHz CPU you'll get above 1e-7 precision,
which is way above accuracy of any crystal oscillator.

> has cc's type changed to 'unsigned int' to prevent problems when rpcc
> overflows.

The only difference is that you'll have extra 'zap' instruction converting
'unsigned int' to 'unsigned long'.

Ivan.