Running Zephyr on NXP S32K344

Preparing S32K344 Evaluation Board for Zephyr Installation

The following hardware setup is required for installing and running a Zephyr sample on the NXP S32K344 Evaluation Board:

• The serial console is provided through “lpuart2” on the 7-pin DCD-LZ debug connector “P6”:

• The SEGGER J-Link is connected to the P26 connector (this is a 10 pin 0.50” space JTAG with the standard pinout used by standard Arm debuggers). Ensure pin 1 on the PCB silkscreen is aligned with pin 1 on the debugger (refer to the picture above).

• The Ethernet connection to the local network using the RDDRONE-T1ADAPT Ethernet media converter connected to the P9 100Base-T1 Ethernet Connector.

• The power is to be supplied at the 5 pin P27 connector at the top left corner of the board (Pin 1-2 power, Pin 3 NC, Pin 4-5 ground). The input voltage range is from 5V to 40V.

Building Zephyr for S32K344 Evaluation Board

Zephyr samples can be built as described in the Zephyr Project documentation:

https://docs.zephyrproject.org/latest/develop/getting_started/index.html

For example, use the following command to build the hello_world sample for the S32K344 Evaluation Board:

cd zephyr
west build -p always -b mr_canhubk3 samples/hello_world

Installing Zephyr on S32K344 Evaluation Board

If the J-Link probe is directly connected to the build machine then the “west flash" command can be used to flash the sample as described in the Zephyr Project documentation:

https://docs.zephyrproject.org/latest/develop/getting_started/index.html

However, it is not always convenient to use the same PC for building and flashing. It is actually enough to install the J-Link software

https://www.segger.com/downloads/jlink/

on the host PC to be able to Flash the boards over the J-Link probe. After installing the J-Link software, verify that the J-Link probe is detected by the SEGGER J-Link Commander and identifies the MCU successfully:

$ JLinkExe -nogui 1 -if swd -speed auto -device S32K344
SEGGER J-Link Commander V7.92c (Compiled Aug 30 2023 14:58:04)
DLL version V7.92c, compiled Aug 30 2023 14:57:42

Connecting to J-Link via USB...O.K.
...
J-Link>connect
...
Cortex-M7 identified.
J-Link>

Create the J-Link Commander script for flashing Zephyr onto the S32K344 Evaluation Board:

$ cat runner.jlink
ExitOnError 1
r
loadfile "zephyr.hex"
r
g
writeDP 1 0
readDP 1
q
$

Put the build/zephyr/zephyr.hex file into the current directory and run the following command:

$ JLinkExe -nogui 1 -if swd -speed auto \
> -device S32K344 -CommanderScript runner.jlink
...
Downloading file [zephyr.hex]...
Comparing flash   [100%] Done.
Erasing flash     [100%] Done.
Programming flash [100%] Done.
J-Link: Flash download: Bank 0 @ 0x00400000: 1 range affected (57344 bytes)
J-Link: Flash download: Total: 0.661s (Prepare: 0.082s, Compare: 0.055s, Erase: 0.032s, Program & Verify: 0.442s, Restore: 0.049s)
J-Link: Flash download: Program & Verify speed: 126 KB/s
O.K.
...
Script processing completed.

$

As soon as a Zephyr image is flashed, it can be started by resetting the board using the reset button or the “reset/go" command sequence of the J-Link Commander:

$ JLinkExe -nogui 1 -if swd -speed auto -device S32K344
...
J-Link>connect
...
J-Link>reset
...
J-Link>go
J-Link>

Now you can connect to the target serial console using a terminal program on your Linux PC, for example:

$ picocom -b 115200 /dev/ttyUSB0
...
Type [C-a] [C-h] to see available commands

Terminal ready

Depending on the installed Zephyr application, you will see some output on the serial console after reset. The Zephyr banner is usually printed:

*** Booting Zephyr OS build emcraft-ef041c6-2-gdaa341a973af ***

Controlling S32K344 Evaluation Board LEDs from the NAVQ+ Kit

Emcraft provides the simple Zephyr demo (emcraft/app/led_network_control) that allows to control the board LEDs from the NAVQ+ kit over the local network.

1. Before building the demo, choose a static IP address for your target board and configure the demo appropriately, for example:

   $ grep CONFIG_NET_CONFIG_MY_IPV4_ADDR emcraft/app/led_network_control/prj.conf
   CONFIG_NET_CONFIG_MY_IPV4_ADDR="192.168.0.111"
   $

2. Build the led_network_control sample for the S32K344 Evaluation Board:

   cd zephyr
   west build -p always -b mr_canhubk3 emcraft/app/led_network_control

3. Install the demo on the target board as described above. If you connect to the target serial console, you will see the following output after reset:

   *** Booting Zephyr OS build emcraft-ef041c6-2-gdaa341a973af ***
   user_led1_green: ready
   user_led1_blue: ready
   user_led1_red: ready
   Single-threaded TCP server waits for a connection
       on address 192.168.0.111 port 4242...

4. From the NAVQ+ console, connect to the target board using telnet:

   $ telnet 192.168.0.111 4242
   Trying 192.168.0.111...
   Connected to 192.168.0.111.
   Escape character is '^]'.
   
   list: print supported LEDs
   <LED> on: turn on the specified LED
   <LED> off: turn off the specified LED
   
   

5. Type “list" to see the available LEDs on the target board:

   list
   user_led1_green
   user_led1_blue
   user_led1_red
   
   

6. Turn user_led1_green on and off:

   user_led1_green on
   OK
   
   user_led1_green off
   OK