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    SubjectRe: [PATCH] 2.4: variable HZ
    On Fri, Oct 18, 2002 at 03:38:43PM -0400, Richard B. Johnson wrote:
    > If you are not using ELAN, CLOCK_TICK_RATE is 1193180.

    well, in fact it's 1193181.666... (14318180/12).

    > If your HZ is 100, you have 1193180/100 = 1193.18, not too exact.

    you meant 1000, I suppose ?

    > if you use 500, you get 1193180/500 = 2386.36 which has twice as much
    > round-off. If you use 1193180/512 = 2330.43, even a higher fractional
    > part.

    those interested can try 511 Hz (/2334.994) or 1900 Hz (/627.990) which
    has the double advantage of being multiple of 100 Hz and have a little
    drift due to frac part (/628 gives 1899.97 Hz, and /627 gives 1903.001 Hz).
    If you don't need a multiple of 100 Hz, I noticed that dividing by 5709
    gives 209.0001 Hz.

    I'm also wondering why we never use the RTC as an interrupt source. Are
    there any incompatible PCs ?

    Cheers,
    Willy

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