Continuous acquisition from LIS3DSH

[aaron239955_stm1_stmicro]

Posted on February 12, 2015 at 16:24

Hello

I'm attempting to acquire continuous data at high rate from a LIS3DSH, and getting discontinuities in the data - any input / suggestions / feedback would be hugely appreciated.  The aim is full rate of 1600 S/s, but 800 S/s would be OK.  Only one channel is required (Y seems to be lowest noise).  The sensor is being communicated with over an I2C bus at 400 kHz.  Both FIFO and direct reading has been tried. - What is a sensible maximum data rate on a 400 kHz I2C bus? - Is it possible to use the FIFO and read only a single channel? - What is the most likely cause of discontinuities in the data - these seem weakly correlated with a larger number of elements in the buffer, but there is no evidence we are getting anywhere near the maximum 32 elements - see attached image Thanks! Aaron #odr #fifo #lis3dh #accelerometer

[aaron239955_stm1_stmicro]

Posted on February 17, 2015 at 12:37

Is there a limitation that the accelerometer cannot mediate between FIFO reads and writes, therefore when reading multiple elements over a slow bus such as I2C you can lose data, as reading from the FIFO blocks the ability to write