Date: Thu, 29 May 2003 22:29:05 -0400
Message-Id: <200305300229.h4U2T5vd031704@envy.delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: killer DOT lightspeed AT bigpond DOT com
CC: djgpp-workers AT delorie DOT com
In-reply-to: <3ED6C0EB.3080403@bigpond.com> (message from Ben Peddell on Fri,
	30 May 2003 12:24:43 +1000)
Subject: Re: uclock() still out by 1 in 65536
References: <4wyBa.45993$1s1 DOT 615094 AT newsfeeds DOT bigpond DOT com> <200305300208 DOT h4U28vDV031441 AT envy DOT delorie DOT com> <3ED6C0EB DOT 3080403 AT bigpond DOT com>
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Please keep djgpp-workers on the recipient list.

> >If the count's wrong, it's a bug.  The question is - are we *supposed*
> >to be counting to 65535, or 65536?  IIRC there are some oddities in
> >how the timer works.
> >
> >  
> >
> Well, the code programs a count of 65535:
> 
>     outportb (0x43, 0x34);
>     outportb (0x40, 0xFF);
>     outportb (0x40, 0xFF);
> 
> whilst it assumes a count of 65536:
> 
>     rv = ((uclock_t)tics << 16) | (msb << 8) | lsb;
> 
> I'll check it on the real PIT, and get back to you.

No, my question was whether a count of 65535 was required to get the
total tic count correct for a day.