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Updated filtering algorithm from transmitter

The Dx4e transmitter (currently that's what I'm using) creates alot of noise when used with arduino. It's quite clear that the receiver has a tuned low pass filter that needed to be emulated for the code.
A low pass filter was implemented with a stategy of using a the gradient of 3 values to determine whether allow input to the servo signal stream or not. Here's the pseudo code below:



  // check for ascending/descending trend in signal prior
  // to including current filtered signal - then update servo signal

  if ((temp_pulse[1] > temp_pulse[0]) && (temp_pulse[2] > temp_pulse[1]))
  {
    *out_pulse = temp_pulse[2];
  }
  if ((temp_pulse[1] < temp_pulse[0]) && (temp_pulse[2] < temp_pulse[1]))
  {
    *out_pulse = temp_pulse[2];
  }

This works quite nice and combination of a low pass filter improved the signal interrupt to the servos while the other sub-systems are executing. First flight test with sensor logging capability.

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