Acquiring Data from an ADXL335 Accelerometer

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Acquiring Data from anADXL335 Accelerometer
living with the lab
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DKSB1002A Evaluation Board and ADXL335
Accelerometer

• DKSB1002A is a prototyping board purchased for
  20 from Digikey
• Screw holes for mounting board onto object of
  interest
• Board is 20mm square
• ADXL335 3-axis accelerometer chip
• 3-axis
• 3g

this small chip is the ADXL335 accelerometer(this
is an older model . . . they are even smaller
now)

• COM - ground
• VSS - power (we will provide 5V)
• X - acceleration in x-direction
• Y - acceleration in y-direction
• Z - acceleration in z-direction

z
x
the DKSB1002A is a board used to evaluate the
accelerometer if you were putting an
accelerometer in a device like a cell phone, you
would only use the ADXL335 chip (and maybe some
capacitors)
y
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Implementing a 3-axis Accelerometer Wiring to
Arduino

• COM - ground
• VSS - power (we will provide 5V)
• X - acceleration in x-direction
• Y - acceleration in y-direction
• Z - acceleration in z-direction

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Programming
void setup() Serial.begin(9600) void
loop() int xaccel analogRead(0) int
yaccel analogRead(1) int zaccel
analogRead(2) unsigned long timevar
millis() Serial.print(timevar)
Serial.print(" ") Serial.print(xaccel)
Serial.print(" ") Serial.print(yaccel)
Serial.print(" ") Serial.println(zaccel)
associates a time with each set of accelerations
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Calibration
 
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Angle Measurement
 
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Example Application
The piezospeaker below outputs a frequency that
varies with the acceleration in the x-direction.
The equation for computing the frequency is
chosen so that the device makes an audible noise
that varies when rotating or shaking the device.
void setup()Serial.begin(9600) void
loop() int xaccel analogRead(0) int
freq 1500xaccel2 tone(7,freq)
Serial.print(xaccel) Serial.print(" ")
Serial.println(freq)