Has anyone else seen data read from the MMA8451Q FIFO in Y-Z-X order, instead of as XYZ as normal?
I have written some functions to use I2C to configure initial settings for 8/14 bit data, ODR, HPF, Range etc. All of which seem to be OK.
Recently I added i2c 'burst' reading to do FIFO access, which also seems good.
However, a couple of days ago I was testing reading from the FIFO & changing the data size from 14-bits to 8-bits. I cannot say if I did anything to
trigger the change, but I noticed the pattern of FIFO data being read had changed from 0, 0, -1024 into 0, -1024, 0 [my device was completely stationary].
This ordering continued for subsequent FIFO reads. It only happened once & has not been reproduced.
Two ideas I had:
1. I2C burst reading had failed somehow in the sequence after reading X, but before Y & Z. So the next fifo byte available would be Y.
BUT, I expect the FIFO would correct itself from this situation for the next i2c command.
2. When changing between 8 & 14 bit modes I put the mma8451q in Standby but did not disable the FIFO (my Bad).
Do you think this mistake could be the cause?
Any comments or assistance would be greatly appreciated.