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Added code for ADXL345 accelerometer
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Adafruit_ADXL345/Adafruit_ADXL345.py

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#!/usr/bin/python
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# Python library for ADXL345 accelerometer.
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# Copyright 2013 Adafruit Industries
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# Permission is hereby granted, free of charge, to any person obtaining a
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# copy of this software and associated documentation files (the "Software"),
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# to deal in the Software without restriction, including without limitation
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# the rights to use, copy, modify, merge, publish, distribute, sublicense,
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# and/or sell copies of the Software, and to permit persons to whom the
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# Software is furnished to do so, subject to the following conditions:
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# The above copyright notice and this permission notice shall be included
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# in all copies or substantial portions of the Software.
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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# DEALINGS IN THE SOFTWARE.
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from Adafruit_I2C import Adafruit_I2C
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class Adafruit_ADXL345(Adafruit_I2C):
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# Minimal constants carried over from Arduino library
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ADXL345_ADDRESS = 0x53
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ADXL345_REG_DEVID = 0x00 # Device ID
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ADXL345_REG_DATAX0 = 0x32 # X-axis data 0 (6 bytes for X/Y/Z)
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ADXL345_REG_POWER_CTL = 0x2D # Power-saving features control
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ADXL345_DATARATE_0_10_HZ = 0x00
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ADXL345_DATARATE_0_20_HZ = 0x01
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ADXL345_DATARATE_0_39_HZ = 0x02
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ADXL345_DATARATE_0_78_HZ = 0x03
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ADXL345_DATARATE_1_56_HZ = 0x04
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ADXL345_DATARATE_3_13_HZ = 0x05
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ADXL345_DATARATE_6_25HZ = 0x06
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ADXL345_DATARATE_12_5_HZ = 0x07
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ADXL345_DATARATE_25_HZ = 0x08
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ADXL345_DATARATE_50_HZ = 0x09
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ADXL345_DATARATE_100_HZ = 0x0A # (default)
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ADXL345_DATARATE_200_HZ = 0x0B
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ADXL345_DATARATE_400_HZ = 0x0C
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ADXL345_DATARATE_800_HZ = 0x0D
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ADXL345_DATARATE_1600_HZ = 0x0E
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ADXL345_DATARATE_3200_HZ = 0x0F
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ADXL345_RANGE_2_G = 0x00 # +/- 2g (default)
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ADXL345_RANGE_4_G = 0x01 # +/- 4g
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ADXL345_RANGE_8_G = 0x02 # +/- 8g
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ADXL345_RANGE_16_G = 0x03 # +/- 16g
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def __init__(self, busnum=-1, debug=False):
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self.accel = Adafruit_I2C(self.ADXL345_ADDRESS, busnum, debug)
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if self.accel.readU8(self.ADXL345_REG_DEVID) == 0xE5:
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# Enable the accelerometer
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self.accel.write8(self.ADXL345_REG_POWER_CTL, 0x08)
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def setRange(self, range):
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# Read the data format register to preserve bits. Update the data
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# rate, make sure that the FULL-RES bit is enabled for range scaling
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format = ((self.accel.readU8(self.ADXL345_REG_DATA_FORMAT) & ~0x0F) |
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range | 0x08)
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# Write the register back to the IC
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seld.accel.write8(self.ADXL345_REG_DATA_FORMAT, format)
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def getRange(self):
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return self.accel.readU8(self.ADXL345_REG_DATA_FORMAT) & 0x03
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def setDataRate(self, dataRate):
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# Note: The LOW_POWER bits are currently ignored,
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# we always keep the device in 'normal' mode
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self.accel.write8(self.ADXL345_REG_BW_RATE, dataRate & 0x0F)
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def getDataRate(self):
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return self.accel.readU8(self.ADXL345_REG_BW_RATE) & 0x0F
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# Read the accelerometer
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def read(self):
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raw = self.accel.readList(self.ADXL345_REG_DATAX0, 6)
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res = []
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for i in range(0, 6, 2):
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g = raw[i] | (raw[i+1] << 8)
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if g > 32767: g -= 65536
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res.append(g)
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return res
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# Simple example prints accelerometer data once per second:
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if __name__ == '__main__':
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from time import sleep
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accel = Adafruit_ADXL345()
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print '[Accelerometer X, Y, Z]'
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while True:
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print accel.read()
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sleep(1) # Output is fun to watch if this is commented out

Adafruit_ADXL345/Adafruit_I2C.py

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../Adafruit_I2C/Adafruit_I2C.py

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