LPS27HHTW in SPI mode

[mdbot]

If the LPS27 pressure sensor works fine under I2C, I cannot make it repond through the SPI bus.
The SPI interface is setup as 4-wire Motorola format (phase 1 polarity 1). CS, the clock SCP and SDI are driven from the SPI controller; SDO is connected to the SPI interface POCI pin. 
Is there something I forgot? Is there a special configuration to setup at power up to avtivate the LPS27 SPI interface?
I don't know what else I could try.

[Smithson]

I cannot help you directly, but from many years of struggle, ok June 2024, I know your answer will be buried in the documentation somewhere.  I assure that having done this a lot that you have to read everything carefully and you will ultimately maybe perhaps no promises find an answer.  

I struggled for five hours over 2 days to get the Sensor tilebox pro wokring on a new machine.  The steps are so convoluted.

Good luck.  

I know that the rate of response on this board, suggests that no one cares, I hope you find a solution.  

[Federica Bossi]

Hi @mdbot ,

There is no special “enable SPI” register on the LPS27HHTW. Make sure you:

• use mode 3
• send the read bit in the register address
• ensure CS is correct at boot
• verify VddIO

[mdbot]

Thank you for your response.
I use mode 3, the read bit is at its right place on bit 7 of register address. VddIO is at 3.3V.
What do you mean "ensure CS is correct at boot"? What is correct? Low? High? The controller drives CS low only during a SPI transaction. Should it be low during startup? I did not see this mentionned anywhere in the documentation.

[mdbot]

Or precisely not in the documentation, I have seen that too.
And this is why I was asking.

Thank you for your message!