piclist 2000\11\09\145509a >
Thread: another challenge
www.piclist.com/techref/microchip/devices.htm?key=pic
flavicon
face BY : Dwayne Reid email (remove spam text)



At 01:56 PM 11/9/00 -0500, M. Adam Davis wrote:
>What you've told us so far:
>Two 9 bit numbers, A and B
>A + B is constant, so B is inversely proportional to A.
>  There is a constant (A + B)
>  This means their relationship is linear,
>  Given A, B could be determined (and vice versa)
>  (ie, A+B=512, 512-A=B, 512-B=A, etc if 512 is the constant)

I'm getting in trouble here because I'm not speaking precisely enough.

A + B = C

X is not a constant per se - its just that for a given set of components
and ambient temperature, A increases by the same amount that B
decreases.  I find C when I've measured both A and B.

>So, your equation
>X = (remainder of) ( (A+B)/B )
>is actually X = B MOD Constant  (MOD being the remainder of the division
>Constant/B)

This is where I'm not speaking precisely enough - I don't have a constant
that I can work with at compile time.  I find (a+b) only after I've
measured both a & b during operation.

>So far, as I understand it, you are modeling a three terminal pot
>(terminals 1,2,3, with 2 being the wiper).  A represents the resistance
>between 1 & 2, B the resistance between 2 & 3, so A + B is the total
>resistance of the POT, which is constant.

Its the best analogy I could come up with.  The application is for
differential sensors, both resistive and capacitive.

As I mentioned in my first message, what I'm looking for is x = (remainder
of) (a+b) / b or, as you more correctly state: x = b MOD (a+b).

My first message said "I have 2 - 9 bit numbers that I need to find the
ratio of, where the ratio is expressed as a number from 00 to FF."  I guess
what I failed to express clearly enough was that the ratio was "b" (top
part) and a+b (bottom part).  Sorry for being imprecise.

dwayne



Dwayne Reid   <dwayner.....spamplanet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax

Celebrating 16 years of Engineering Innovation (1984 - 2000)

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
commercial email nor is intended to solicit commercial email.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics





seeking: ubicom lib mem memory
<4.3.2.7.2.20001109122948.00cdc140@pop.telusplanet.net>

In reply to: <3A0AF371.2ED1D136@ubasics.com>
See also: www.piclist.com/techref/microchip/devices.htm?key=pic
Reply You must be a member of the piclist mailing list (not only a www.piclist.com member) to post to the piclist. This form requires JavaScript and a browser/email client that can handle form mailto: posts.
Subject (change) another challenge

month overview.

new search...