File content as of revision 30:9e127911409d:

# Documentation for Vibration Detection

Our algorithm is fairly simple right now; it measures knocks by comparing x, y, and z
values to an initial baseline set of values. When the program starts, it saves
initx, inity, and initz (uint8_t values); these are the initial baseline values for
each axis of measurement for the accelerometer. The program then enters a
perpetual while loop that measures x, y, and z and compares those new measurements
to their respective initial values. If any of these measured values vary from their
initial values by more than 2 (in either a positive or negative direction), the
LED lights for 2 seconds and measurement pauses. After those 2 seconds, measurement
resumes.

This algorithm assumes 2 main things about the evironment: that any knock is
significant enough to change the measured value from the initial value by at least 3,
and that the baseline does not change (that is, that the board's orientation is fixed
during program execution).

# Documentation on Altimeter Measurement

Our altimeter code (measureAlt()) reports the atmospheric pressure in Hecto-Pascals and
temperature in Celcius, retrieved from the appropriate registers at a rate of 10Hz.
The function saves the first 1000 measurements into an array of doubles (doubles being
the returned values of both our pressure and temperature measurements), arranged in
order of measurement. (data[0] is the first pressure measurement, data[1] the first
temperature measurement, data[2] is the second pressure measurement, and so on.)

If the buffer is filled or a keypress is registered from the PC, measureAlt() stops
measuring and shows a basic input prompt, "p%". If the interrupt was from a keypress,
the key pressed is echoed as well. If the user types 'p' and then 'enter', the
measurements taken are printed to the terminal in the following format:

    %PRESSURE%  %TEMPERATURE%\n\r
    
(Example actual output is shown below.)

Once the measured values have been printed, the function exits successfully.

    #A note on our implementation
    Currently, our code relies on being connected to a pc with a keyboard as it is
    measuring values. This is a limitation of our code that we are attempting to
    (and fully plan to) address.
    
    In addition, our code does not include the GPIO pin at the moment because screen
    breaks when it is added.
    
Example output:

98763.000000    22.187500
98763.000000    22.187500
98763.000000    22.187500
98763.000000    22.187500
98763.000000    22.187500
98763.000000    22.187500
98763.000000    22.187500
98763.000000    22.187500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98749.000000    22.062500
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98797.000000    22.250000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98785.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98794.000000    22.125000
98842.000000    22.250000
98842.000000    22.250000
98842.000000    22.250000
98842.000000    22.250000
98842.000000    22.250000
98842.000000    22.250000
98842.000000    22.250000