First,
here is the sensor manual from 2011. We found it sortof helpful in first learning how to use the sensor.
Some notes:
For SPI, there's a hazy memory about not having the right DIO selected for a specific input from the SPI interface on the accelerometer, refer to the sensor manual or the datasheet for the ADXL345 to learn about what the various acronyms on the board are actually for (and thus know you have the right DIO selected in the LV example.)
- I2C has been the most hasslefree for us
- the code in the WPILib for the I2C ADXL345 expects a default hardware address, find out what that is. (For example, with I2C, we had plugged the 4 wires into the wrong I2C ports, and just moved it to the other ones. Hey presto, it worked.)