using SPI0 and LTE together throws a fault

[vchhabra]

Was wondering if anyone knew why this fault might be triggered?

It triggers when I try to use SPI0 and LTE together.

AT host is disabled.

The code stops here during debugging and then on resume it restarts the application.

fault_s.S line 90

#if defined(CONFIG_ARMV6_M_ARMV8_M_BASELINE) || \
    defined(CONFIG_ARMV7_M_ARMV8_M_MAINLINE)
    mrs r0, MSP
    mrs r1, PSP
    mov r2, lr /* EXC_RETURN */

[Didrik Rokhaug]

Hi.

SPI0 is using the same hardware as UART0, so you can not use those two at the same time.

Are you using logging in your application?

Are you disabling the serial drivers (CONFIG_SERIAL=n)?

Have you configured the SPM to set up SPI0 as non-secure?

Is there a reason why you are using SPI0 instead of SPI2 which is configured by the SPM by default?

Do you know what the last thing that happens before you enter the fault handler is?

Could you share your <your build folder>/zephyr/.config and <your build folder>/zephyr/zephyr.dts files?

Best regards,

Didrik

[vchhabra]

I do have a question in the meantime. Is it necessary to use UART with LTE or can we completely disable the UART without any issues from the drivers?

[Martin]

If you refer to the 'bsdlib' (socket interface) then I have a custom board that has no serial port and the LTE modem is working fine.

But if your question is for the DK or Thingy you might have to modify the software a bit ...

[vchhabra]

We have a custom board package for our custom board. Issue is we cannot turn off serial as we use UART1 for communicating with the nrf52840. That's why I was wondering if something else is using UART.