From: Mike Monett
X-Mailer: Mozilla 2.02 (Win16; I)
Subject: Re: What makes coils AC or DC??
References: <2DoU9.22597$jM5.email@example.com> <firstname.lastname@example.org> <3E223E27.367C@sneakemail.com>
Date: Mon, 13 Jan 2003 08:08:10 -0500
NNTP-Posting-Date: Mon, 13 Jan 2003 08:07:40 EST
Organization: Bell Sympatico
John Larkin wrote:
> Well, for instance, I did a timing gadget that had a 77.76 MHz clock
> (1/2 OC3 rate) but was programmed in integer picoseconds, 48 bits of
> same. So to convert the customer's requested time into my internal
> format (ie, N clock ticks and M bits of interpolation vernier: 16 bits
> of vernier) I had to do a multiply by a scaler that would partition
> the result into nice bit clusters, N.M bits. Simple enough (all in
> bare-metal 68K assembly), but I couldn't find a calculator anywhere
> that would do the math to 48-bit precision.
> The problem reduced to multiplying by something like 5.09607936...,
> which I did by multiplying by 8 (just a shift) then a fractional
> multiply by 0.637..., which factor I couldn't get anything to
> calculate accurately.
> Everything I tried missed by too much. In the end, I just tweaked the
> scaler manually until it gave me the right answer: it was...
> 0.A3131505A0BB0000 hex
> So what I needed was an infinite-resolution calculator that worked in
> hex, with decimal point (heximal point?) included.
LOL! When conventional methods won't work, find a simpler method. I love
Thanks, John. First laugh of the day:)