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Hello I am trying to set the registers for BMA253 and was looking at the source code - in BMA2-Sensor-API  bma2.c - and I have a few questions. I am looking at v0.3.0  On line 726, in bma2_set_accel_conf() function, it is reading the register 0x11(PMU_LPW) and that doesn't make sense. below is the code snippet: -------------------------------------------------------------------------------------------------------------------------------------------- Line726: rslt = bma2_get_regs(BMA2_REG_PMU_LPW, reg_data, 2, dev); Line727: Line728: if (rslt == BMA2_OK) Line729: { Line730: reg_data[0] = BMA2_SET_BITS_POS_0(reg_data[0], BMA2_RANGE, accel_conf->range); Line731: reg_data[1] = BMA2_SET_BITS_POS_0(reg_data[1], BMA2_BW, accel_conf->bw); Line732: Line733: /* Set the values in the accel configuration registers */ Line734: rslt = bma2_set_regs(BMA2_REG_PMU_RANGE, reg_data, 2, dev); -------------------------------------------------------------------------------------------------------------------------------------------- it is reading from 0x11(PMU_LPW) , setting the range and bandwith and writing it to 0x0F(PMU_RANGE). shouldn' t it be getting from register 0x0F(PMU_RANGE)? (it doesn't really matter because PMU_LPW is 0x00 and you are setting the reg_data with your range and bw)   The code just after this is, I think, setting 0x3 in the reserved bit. (Line742) code snippets below: ------------------------------------------------------------------------------------------------------------------------- Line736: if (rslt == BMA2_OK) Line737: { Line738: reg_data[0] = BMA2_SET_BITS(reg_data[0], BMA2_SHADOW_DIS, accel_conf->shadow_dis); Line739: reg_data[0] = BMA2_SET_BITS(reg_data[0], BMA2_DATA_HIGH_BW, accel_conf->data_high_bw); Line740: Line741: /* Set the values in the accel config register */ Line742: rslt = bma2_set_regs(BMA2_REG_ACCD_HBW, &reg_data[0], 1, dev); ------------------------------------------------------------------------------------------------------------------------- when i printf the reg_data , reg_data[0] has 0x03 when setting data to register 0x13(ACCD_HBW). In the case of BMA253, according to the data sheet, bit7 and bit6 is for data_high_bw and shadow_dis. bit5 to bit0 are for reserved and setting 0x03 means strange because you set data on the reserved bit. I think you have previous data (pmu range) in reg_data[0]. it seems that you should be calling bma2_get_regs() function with parameter 0x13(ACCD_HBW) before setting reg_data[0] on line738. that's all. I appreciate if you could give me a feedback. ... View more

Hi I want to set  the free-fall detection of BMA253 like BMA400. I read this post (Free Fall detection on BMA456) , that references this post (BMA400 Fall detection) which gives the freefall tutorial pdf file and says Low G feature is equal to free fall detection after configure correctly like BMA400 . I am trying to set the registers of BMA253 like BMA400 referencing the above tutorial, but the registers of the two sensors aren't exactly the same. For Example BMA400 has settings for OSR in register 0x1A but BMA253 doesn't have any setting for OSR in any of the registers, and so on... I will be appreciated if you could show me the configuration for BMA253 for Low-g detection (free-fall detection).   ... View more