Hi,
1. When BMA253 is set to +/-2g full scale range, 1LSB for tap_th<4:0> in register 0x2B corresponds to 62.5mg. The pseudo code in the technical document uses 0x04 for tap_th<4:0> as an example. It means that the tap threshold is 62.5mg/LSB * 4LSB = 250mg. If you set tap_th<4:0> to 0x10 then the tap threshold will be 62.5mg/LSB * 16LSB = 1000mg = 1g.
The same applies to slope_th<7:0> in register 0x28. When BMA253 is set to +/-2g full scale range, 1LSB for slope_th<7:0> corresponds to 3.91mg. If you set slope_th<7:0> to 0x10 then the slope threshold will be 3.91mg/LSB * 16LSB = 62.56mg. Slope means the current acceleration value minus previous acceleration value, i.e. Delta ax_t = ax_t - ax_t-1 for x axis. If Delta ax_t is beyond the slope_th threshold for the amount of duration, then slope interrupt or any-motion interrupt will be generated. BMA253 single-tap and double-tap interrupts use Delta ax, ay, az as input.
2. When BMA253 bandwidth is set to 1000Hz, the sampling rate is 2000Hz which means the sample time is 0.5ms. Please see the attached Excel file for more information.
Thanks.
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