<div dir="ltr"><br><br><div class="gmail_quote">On Sat, Sep 20, 2008 at 4:07 PM, Joel Newkirk <span dir="ltr"><<a href="mailto:freerunner@newkirk.us">freerunner@newkirk.us</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I wrote a short shell script to repeatedly take the raw output from one of<br>
the accelerometers (/sys/devices/platform/spi_s3c24xx_gpio.1/spi0.1/dump)<br>
and massage the data to output X,Y,and Z-axis readings in decimal, -128 to<br>
128.<br>
<br>
With my Freerunner sitting flat, face up, on the concrete slab of my house,<br>
the 'Z' reading (positive Z is toward the back of the handset, BTW)<br>
fluctuates between 51 and 56. (X and Y range from -1 to 2) That's a<br>
variance of +/- 5%, and I'm fairly confident gravity isn't fluctuating<br>
significantly... ;)<br>
<br>
Is that to be expected, is my Freerunner defective, or am I doing something<br>
wrong?<br>
<br>
I'm trying to develop a simple tool that will determine 'down' based on<br>
output from the accelerometer, and indicate deviations from various<br>
90-degree orientations - will I need to massage the data further to ignore<br>
variations, should I be averaging several readings, or what?<br>
<br>
j<br>
<br>
<br>
<br>
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</blockquote></div><br>j<br><br>As a bit OT but since you have gone to the trouble of developing the script, could you run a test while driving/riding in the car and post what the readings might be? I was thinking of the possibility of having the FR determine if it was in a moving car or not.<br>
<br>Mike<br clear="all"><br>-- <br>Michael Fisher<br><a href="mailto:desNotes@gmail.com">desNotes@gmail.com</a><br>
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