nRF52832 with external Infineon OPTIGA Trust X

[ezamp]

Hello,

I would like to save some keys securely using the Infineon OPTIGA Trust X chip. To do a quick test I bought the Infineon shield2Go with the OPTIGA chip that I connected to the EVK-ANNA-B112 dev kit produced by Ublox (based on nRF52832).

I tried running the example [SDK 17.0.2]/examples/crypto/nrf_crypto/test_app/pca10040_optiga/ses but in debug I get a return error when the nrf_crypto_init () function is called (ret val equal to 0x03).

I connected the Infineon shield using the pins on the bottom part and I connected the reset pin as described in the official document. The connections follow the pin definition in the pal_pin_config.h file.

Am I running the wrong example?

Thanks in advance for the help!

[Kenneth]

I have not used the OPTIGA Trust X chip (don't have one here at the home office), but from my understanding it is using i2c as serial interface, and I suspect the error code is that the i2c is not able to communicate with the chip (either invalid pins, missing pull-up resistors, wrong i2c address, chip not powered, grounding missing or similar). I can see similar error code when running the example as-is with no chip connected:

There is little information in the description of the example:
https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/ifx_optiga_custom_example.html

My suggestion is to hook up a logic analyzer to the i2c interface and check if there is communication on the i2c, that may give some indication of the problem that I may relay to the team that have worked on the example.

I used the \examples\crypto\ifx_optiga_custom_example as example project here.

[ezamp]

Thanks for the reply.

From the logic analyser I have seen that SDA and SCL always remain high. Unfortunately the SDA and SCL pins were incorrectly enumerated, correcting this error the code works.

Thanks!