🚀 go-pugleaf

bomgard@iuvax.cs.indiana.edu (Tim Bomgardner) writes:
>filetp@dnlunx.pttrnl.nl (Peter Filet) writes:
>> (wants a faster system clock)

>This is actually very easy to do.  The idea is to hook the clock tick 
>interrupt, keeping the original vector and substituting your own handler.
>Then, if you
>want, say, a 4X clock rate (72.8/sec), you call the original handler every
>fourth tick.  The rest of the OS has no idea anything has changed.  Indeed,
>from its point of view, nothing has.

The rest of the "OS" (if you call DOS that), maybe -- but some other
TSR may be peeking at the 8253's registers periodicaly to see how long
it has been since the last tick, and they will get mighty confused if
you've changed the interupt rate by changing the clock-freqency devisor on
the clock-interupt channel of the 8253.

>... Commercial
>software developers can usually tell you how to do it anyway :) .

Assuming the rest of the software is better behaved than theirs'. :-(


-- 
/bill ricker/
wdr@wang.com a/k/a wricker@northeastern.edu
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