[Stephen.Usher@earth.ox.ac.uk: Re: Load average patch for MiNT 1.09.]

[Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>]

From: Stephen Usher <Stephen.Usher@earth.ox.ac.uk>
Subject: Re: Load average patch for MiNT 1.09.
To: schwab
Date: Fri, 11 Feb 1994 09:55:05 +0000 (GMT)
In-Reply-To: <9402110950.AA02543@issan.informatik.uni-dortmund.de> from "Andreas Schwab" at Feb 11, 94 10:50:06 am
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>Stephen Usher <Stephen.Usher@earth.ox.ac.uk> writes:
>
>|> BUGS
>
>|> 	The uptime and load average code uses the Vertical Blank Interrupt
>|> 	to update its values and assumes that the interrupt will happen
>|> 	60 times per second. This is a false assumption on PAL STs running
>|> 	in either ST Low or ST Medium resolutions in which case the uptime
>|> 	clock will run slow.
>
>It's worse than that, in ST High the frame clock is 72 Hz (on
>ST/STe's), and the uptime clock will run too fast. You should never
>make any assumptions about the frequency of the VBI. If you want a
>reliable clock, use etv_timer.

I could have used the 200Hz interrupt but decided that it'd probably use too
much CPU time for that. If anyone wishes to modify my patches to give a
better time accuracy it's fine by me! :-)

Steve

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