nRF9131 EK

Overview

The nRF9131 EK (PCA10165) is a single-board evaluation kit for the nRF9131 SiP for DECT NR+ and LTE-M/NB-IoT with GNSS. The nrf9131ek/nrf9131 board configuration provides support for the Nordic Semiconductor nRF9131 ARM Cortex-M33F CPU with ARMv8-M Security Extension and the following devices:

  • ADC

  • CLOCK

  • FLASH

  • GPIO

  • I2C

  • MPU

  • NVIC

  • PWM

  • RTC

  • Segger RTT (RTT Console)

  • SPI

  • UARTE

  • WDT

  • IDAU

nRF9131 EK

nRF9131 EK (Credit: Nordic Semiconductor)

The Nordic Semiconductor TechDocs [2] will soon contain the processor’s information and the datasheet.

Hardware

nRF9131 EK has two external oscillators. The frequency of the slow clock is 32.768 kHz. The frequency of the main clock is 32 MHz.

Supported Features

The nrf9131ek/nrf9131 board configuration supports the following hardware features:

Interface

Controller

Driver/Component

ADC

on-chip

adc

CLOCK

on-chip

clock_control

FLASH

on-chip

flash

GPIO

on-chip

gpio

I2C(M)

on-chip

i2c

MPU

on-chip

arch/arm

NVIC

on-chip

arch/arm

PWM

on-chip

pwm

RTC

on-chip

system clock

RTT

Segger

console

SPI(M/S)

on-chip

spi

SPU

on-chip

system protection

UARTE

on-chip

serial

WDT

on-chip

watchdog

Connections and IOs

LED

  • LED (red) = P0.29

  • LED (green) = P0.30

  • LED (blue) = P0.31

Push buttons and Switches

  • BUTTON = P0.28

  • RESET

Security components

  • Implementation Defined Attribution Unit (IDAU [1]). The IDAU is implemented with the System Protection Unit and is used to define secure and non-secure memory maps. By default, all of the memory space (Flash, SRAM, and peripheral address space) is defined to be secure accessible only.

  • Secure boot.

Programming and Debugging

nrf9131ek/nrf9131 supports the Armv8m Security Extension, and by default boots in the Secure state.

Building Secure/Non-Secure Zephyr applications with Arm® TrustZone®

Applications on the nRF9131 may contain a Secure and a Non-Secure firmware image. The Secure image can be built using either Zephyr or Trusted Firmware M [3] (TF-M). Non-Secure firmware images are always built using Zephyr. The two alternatives are described below.

Note

By default the Secure image for nRF9131 is built using TF-M.

Building the Secure firmware using Zephyr

The process requires the following steps:

  1. Build the Secure Zephyr application using -DBOARD=nrf9131ek/nrf9131 and CONFIG_TRUSTED_EXECUTION_SECURE=y in the application project configuration file.

  2. Build the Non-Secure Zephyr application using -DBOARD=nrf9131ek/nrf9131/ns.

  3. Merge the two binaries together.

Building the Secure firmware with TF-M

The process to build the Secure firmware image using TF-M and the Non-Secure firmware image using Zephyr requires the following action:

  1. Build the Non-Secure Zephyr application using -DBOARD=nrf9131ek/nrf9131/ns. To invoke the building of TF-M the Zephyr build system requires the Kconfig option BUILD_WITH_TFM to be enabled, which is done by default when building Zephyr as a Non-Secure application. The Zephyr build system will perform the following steps automatically:

    • Build the Non-Secure firmware image as a regular Zephyr application

    • Build a TF-M (secure) firmware image

    • Merge the output binaries together

    • Optionally build a bootloader image (MCUboot)

Note

Depending on the TF-M configuration, an application DTS overlay may be required, to adjust the Non-Secure image Flash and SRAM starting address and sizes.

When building a Secure/Non-Secure application, the Secure application will have to set the IDAU (SPU) configuration to allow Non-Secure access to all CPU resources utilized by the Non-Secure application firmware. SPU configuration shall take place before jumping to the Non-Secure application.

Building a Secure only application

Build the Zephyr app in the usual way (see Building an Application and Run an Application), using -DBOARD=nrf9131ek/nrf9131.

Flashing

Follow the instructions in the Nordic nRF5x Segger J-Link page to install and configure all the necessary software. Further information can be found in Flashing. Then build and flash applications as usual (see Building an Application and Run an Application for more details).

Here is an example for the Hello World application.

First, run your favorite terminal program to listen for output.

$ minicom -D <tty_device> -b 115200

Replace <tty_device> with the port where the nRF9131 EK can be found. For example, under Linux, /dev/ttyACM0.

Then build and flash the application in the usual way.

# From the root of the zephyr repository
west build -b nrf9131ek/nrf9131 samples/hello_world
west flash

Debugging

Refer to the Nordic nRF5x Segger J-Link page to learn about debugging Nordic boards with a Segger IC.

Testing the LEDs and buttons in the nRF9131 EK

There are 2 samples that allow you to test that the button and LED on the board are working properly with Zephyr:

You can build and flash the examples to make sure Zephyr is running correctly on your board. The button and LED definitions can be found in boards/nordic/nrf9131ek/nrf9131ek_nrf9131_common.dtsi.

References