RE: [tracker2] Smartbeaconing settings T2-135
- There's a lot of that base 2 integer math in there. The discriminator for the OT1+ is just a bunch of shifts and adds. The arctangent function uses floating point, but it still cheats with a lookup table and multisegment linear approximation. Makes me wish I'd paid attention in math class. Of course, when I wasn't paying attention in math class it was usually because I was sketching out embedded system designs in my notebook...Anyway, it's these issues with unit conversion that have kept me from implementing the profile switch configuration in the command line interface. Someday soon I'm going to have to figure out how I want to do that.Scott
From: email@example.com [mailto:firstname.lastname@example.org] On Behalf Of James Ewen
Sent: Monday, June 18, 2007 4:49 PM
Subject: Re: [tracker2] Smartbeaconing settings T2-135
On 6/18/07, Scott Miller <scott@opentrac. org> wrote:
> As for why they're used, it originally comes from the fact that the OpenTRAC
> protocol uses centimeters/ second for speed, and that's how the OpenTracker
> stores the speed internally. The profile switch and SmartBeaconing settings are
> 8-bit values, so it shifts the speed right by 5 bits (dividing it by 32) to give it a
> useful range of values.
I figured as much with the 32 value in there. If it were simply a
count you could stop early and come close to km/h. With the simple
math derived from a right shift operation, we'll learn to live with
Thanks again Scott...
- I don't know where Scott posted it, but a FYI that he's been out of
town without his computer for a couple of days. He'll be back later
today, but might be a little buried in email. But it was worth it, if
I can speak for him -- readers in Silicon Valley will know what I'm
talking about when I saw we went over to the Geek Golden Triangle
area in Sunnyvale. Halted, Weird Stuff, Action Computers, Fry's, and
HRO. And missed a couple of other places only because they had already closed.
Have a great field day everyone.
At 09:18 AM 6/23/2007, you wrote:
>At 03:11 PM 6/18/2007, 'Scott Miller' wrote:
> >I updated the manual and included the conversion factors and added a table.
>Where have you posted this revised manual?
- Bob W9RXR wrote...
> Where have you posted this revised manual?Is it the T2-135 manual that you are looking for? Scott referred to a table
and conversion factors which seem to appear in this manual.
73 es cul - Keith VE7GDH
"I may be lost, but I know exactly where I am!"
- At 05:00 PM 6/23/2007, Keith VE7GDH wrote:
>Is it the T2-135 manual that you are looking for? Scott referred toThanks, Keith. That is a more current manual than the one I had.
>a table and conversion factors which seem to appear in this manual.