In support of the Healthcare SMS, I had to rewrite their Heart Rate Monitor code to do sample-by-sample ADXL/ADC reading (i.e. no FIFO mode in the ADXL). But, something weird occured whereby I had to double the ADXL sample rate (from 100Hz to 200Hz) to get an effective 100Hz data rate? With the FIFO on, everything correlated one to one (100Hz rate gave 100 samples per second). Just simply turning off the FIFO caused this. Can you explain?