STEVAL-MKI208V1K (IIS3DWB) and Nucleo-WB55RG : SPI not working, Pin CS at 3.3v?

[NoWayCall]

Hi,

(Since i am not a native speaker i apologize in advance for any mistake i would make.)

I am curently working on a project that require an acelerometer.

For my tests, i am working with a NUCLEO-WB55RG and an eval board STEVAL-MKI208V1K. They are connected together through SPI1 like follows:

Nucleo ---> Eval Board

(SCK) PA5 [D13] ---> SCL

(MISO) PA6 [D12] ---> SDA

(MOSI) PA7 [D11] ---> SDO

(CS) GND ---> CS

When i check the levels i can see that the chip select is somehow at 3.3V !

Is there a register to parameter or something to do to specify that i don't want to use the chip in I2C but in SPI (and so put the CS to ground level).

Thank you in advance ,

Noé.

[Eleon BORLINI · Accepted solution]

Hi Noé @Noé Colle​ ,

I suggest you to first check the SPI communication pattern with an oscilloscope, to have the proper temporal resolution.

However, to be sure you are working in SPI only, you can also set bit I2C_DISABLE=1 in reg 13h in order to disable I2C internal pullups (see IIS3DWB datasheet, p.4 and p.34).

-Eleon