ADXL357 SPI Issue

Hello,

I am using the SPI interface with a 1 MHz clock on the ADXL357B.

The hardware is similar to ADXL357 application circuit on page 21 of the datasheet.

The INT1, INT2 and DRDY are left open.

I can readout all register with their reset values. When I write to a R/W register, I get back only the reset value.

For example I write 0x00 to the register 0x2D to leave standby (start measuring) - but readout is 0x01.

What have I to consider for the hard- and software to get the chip running. Are there software examples available?

 

Thank you in advance

  • 0
    •  Analog Employees 
    on Aug 13, 2019 12:43 AM

    Hi Burkhard,

    Since you can readout all registers and read the default values of these register, your issue might be in SPI write implementation.

    My advice is to check the signal waveform of the SPI using oscilloscope or signal interpreter tool to see if your write implementation is functioning correctly.

    Regards,

    Mark

  • Issue is solved. I am using the wrong SPI mode; only SPI mode 0 is working for read/write. I have some SPI devices on the SPI interface.

    One of the devices uses SPI mode 1 or 3. For testing I switch to SPI mode to 3 and then I could only "read" the ADXL. Sometimes it's

    helpful to read all datasheets! 

    Burkhard