IIS2DH Reading and Clearing FIFO

[apennell001]

Posted on April 12, 2017 at 17:13

I am moving to the IIS2DH from the LIS3DSH because it is end of life. I am having an issue with reading the FIFO. I can enable FIFO mode and it seems to fill and generate an interrupt on OVRN and WTM just fine, but the X, Y and Z high and low registers are all value 0x80. And reading the data does not empty the FIFO. 

Can you suggest what would cause this? Otherwise it seems very similar the LIS3DSH which I have no issues with. 

-AP

[apennell001]

Posted on April 12, 2017 at 20:09

This was resolved. The IIS2DH is a little different than the LIS3DSH in that you need to set the MSB of the register address so the register location auto-increments. See pg. 24 paragraph 4 of the spec sheet. The LIS3DSH did this with a setting in CTRL_REG6.