Hi, I am trying to issue a soft reset (0x7E, 0xB6) in the initilization sequence and for some reason all sequences fail afterwards. So it is of no help to start directly from beginning after the reset is issued (Dummy byte etc. onwards). They pass again when i reset the MCU for some reason, i suspect it has something to do with the SPI pins that are altered during the reset allowing the IMU to cycle. The sensor is not power cycled in the process and i have no control of its power either (VDD and VDDIO come from the source). Serial link is with SPI 4 wire interface. There seems to be very little information on this subject in the manual. edit: I am chasing this more. Particularly soft reset is needed to catch the Gyro self test so not doing it is no solution. Gyro test it seems to be picky on being done early on after POR or soft reset to return its result (0b00001111). So right after the SPI dummy read, i have to issue soft reset and do small 50ms delay (increasing the delay does not help, decreasing fails), then 4 dummy reads at register 0x00. Dummy reads (or any other for that matter) less than 4 times, the Chip ID becomes 0xFF after reset, but even if that happens the subsequent configurations do succeed so definetly this is related to some kind of voltage tickling with SPI pins. Increasing or decreasing the SPI Mhz does not have effect.
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