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Thank You for confirmation.   One last question: If there are no changes in acceleration (theoretically constant velocity) for 300s, software timer will reach 300 and system will detect rest state. Neither ANY_, nor NO_ motion solves that case. Right? ... View more

This means that if you only use BMA280 no-motion interrupt in LPM1, when BMA280 is stationary, then BMA280 will always stay in normal mode that consumes 130uA all the time. I can confirm that. I rewrote the code to use NO_MOTION + ANY_MOTION interrupt swapping (both use pin INT2) and current consumption is good. But: do I then need NO_MOTION interrupt at all? My observation shows (Fluke amperemeter), that ANY_MOTION + LPM1 with 1 second sleep_dur + 300 seconds software timer (any motion causes its reset, by motionlessness is timer incremented) proves the same consumption and BMA doesn't stay in NORMAL mode whether in motion or at rest (PMU_BW = 500Hz, INT_RST_LATCH = 0). Whenever you see any-motion interrupt, you disable it and then enable no-motion interrupt. Why should I do that? Am I forgetting something? ... View more

My observation confirms that Table 19 is correct, but formula for "Delay time" in range 40..80s is wrong. Shouldn't be: slo_no_mot_dur<5:4>=’b01’ -> [slo_no_mot_dur<3:0> . 8 + 40] ? ... View more

Thanks for detailed explanation. To summarize my issue: If I want BMA280 in LPM1 with no-motion functionality, I have to 1. set no-motion interrupt as non-latched (INT_RST_LATCH) 2. use filtered data (not default max ODR in PMU_BW) 3. use software timer to measure pulse width, because BMA280 generates interrupt always (even when in motion) Real application: slo_no_mot_dur = 14 (Delay time 15s) software timer counts up to 285 (seconds), when BMA280 interrupt pulse is high, and resets with every high-to-low pulse transition This ensures max time 300s (5 minutes) for no-motion detection (with max 15s uncertainty, no-motion state can happen sooner than in 300. second, i.e. in 285. second, but must happen in 300. second at the latest) Right? ... View more