Re: [tGarden-dev] help re slow, repeated values

[nik g. <ni...@f0...>]

NOTE:  http://libarynth.f0.am/cgi-bin/view/Libarynth/ProjectTxoomWearables

> it seems that the data coming into oz from one of our wearable
> assembly is too stepped:  as we rotate the sensor slowly, the data
> does not change smoothly with the sensor, but instead jumps at
> approximately  1 second intervals to successive values.   i have to
> look more carefully at the std out from  operate on the ipaq, but it
> could be that

this sounds like a sensor conenciton problem. do you have TWO sensors 
connected to the stamp/pic-box ?+

check the sensor input with the following command on the ipaq
 cat /dev/ttySA0 
should see a stream of raw sensor bytes + channel numbers.

see previous post on thsi topic ->  (quote w/ spelling corrections!)

> > our gvu lab rates seem slow  -- only 
> > a few vectors / sec from the one single! ipaq.   what factors control 
> > or limit the frequency of data from the accelerometer to 802.11b? 
> > (wasn't that a rate fixed at the pic, or does that depend on 
> > available  802.11b speeds/bandwidth?
> 
> we had some very unusual fluctuations  in network behaviour in torino.
> generally it worked better at night, perhaps excessive radiation during the
> day? badly configured cell network? if  you are getting only a few samples
> per second, it might be a sensor or pic problemm since stocks version waits
> quite a while (tens of milliseconds) between sensor channels if no data is
> sent from the sensor. make sure both sensors are plugged into the pic, and
> that they are both working sensors.
>  
> > our little 802.11b network runs only the ipaqs and a mac airport on a 
> > pc.   there's a second mac airport card but that's built into the oz 
> > mac in order for it to get around some draconian sysad restrictions 
> > on our wireless usage.
>
> have a look at some of the wireless monitoring thruput/frame dropping rates
  
more at http://libarynth.f0.am/cgi-bin/view/Libarynth/ProjectTxoomWearables

please consult/append/modify


> (1) the data stream is interrupted somewhere on the
> accelerometer-pic-ipaq chain,
> and
> (2)  some code (in the ipaq?) is repeating fossil data  (which would
> be wrong!  -- we want sensor to push data)
>
> Q1.	i recall that the data acquisition and rebroadcast code (on
> ipaq) was built to poll at a regular cloack rate.   where is that
> rate set, and what was it?
>
> Q2.	what could possibly affect this slow, delayed episodic
> response to changes in the sensor ?
>
> we put every mac on a hub disconncetd from the ambient net, so they
> see only one another.  the only difference is that i'n using an
> Airport base station to send data htough it's tittanium.
>
> and
>
> Q3.	what can we do to speed up the frequency?
>
> please help, any suggesions?

more at http://libarynth.f0.am/cgi-bin/view/Libarynth/ProjectTxoomWearables