Thanks Joe, I appreciate the response. I'll keep all that in mind. I noticed that on POR the device starts up with Advanced Power Save (APS) mode enabled and in the datasheet they indicate it should be turned off after switching to SPI mode. This doesn't occur in the official driver, so perhaps that's an issue with this revision of chips. I perform a dummy read to switch to SPI and then turn APS off before initializing via the driver and it appears to work so far. Not the first workaround I've had to implement with a Bosch MEMS chip and probably won't be the last.
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I have a custom board leveraging the official BMI270 driver and I'm having inconsistent results when initializing the chip. I'm using the official Github based driver. On startup a dummy read of CHIP_ID is performed and the BMI270 does not reply. This should put it in SPI mode per the datasheet. At least 450us later a real read of CHIP_ID is performed with mixed results. When using a SPI clock of 6MHz (CPOL=CPHA=0) it responds, but the bits are often shifted or wrong altogether about 50% of the time. With a 1.5 MHz SPI clock (CPOL=CPHA=0) this initialization works every time. From the datasheet it states that the device powers up in APS mode. Does this require a slower clock until it's turned off? Should it work with up to 10 MHz every time.
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