Embedded module TQMaRZG2x - YOCTO Linux BSP documentation


The MBaRZG2x provides the CAN interfaces CAN1 and CAN2.

CAN configuration

DIP switch S10 is used to configure the CAN interfaces CAN0 and CAN1.

Function S1-1 S1-2
CAN-Bus not terminated OFF OFF
not defined (illegal state) OFF ON
not defined (illegal state) ON OFF
CAN-Bus terminated with 120 Ohm ON ON

CAN Loopback

CAN FD can not be automatically configured by systemd machine units due to a limitation in the systemd version in Yocto Zeus,
it can be enabled by the following commands in the shell:
ip link set can0 down
ip link set can0 up type can bitrate 500000 sample-point 0.75 dbitrate 4000000 dsample-point 0.8 fd on
ip link set can1 down
ip link set can1 up type can bitrate 500000 sample-point 0.75 dbitrate 4000000 dsample-point 0.8 fd on

CAN0 -> CAN1

candump can0&
cansend can1 5A1#11.2233.44556677.88

CAN1 -> CAN0

candump can1&
cansend can0 5A1#11.2233.44556677.88


The STKRZG2X Starterkit provides one Gigabit Ethernet interfaces.


In U-Boot eth0 is configured as default interface. The IP configuration can be done statically or by a DHCP server in the network.

IP configuration via DHCP

For a configuration via a DHCP server, use the dhcp command in U-Boot.

Static IP configuration For a static IP configuration the following, U-Boot environment variables must be set:

setenv ipaddr <ipaddr> 
(e.g.: setenv ipaddr
setenv netmask <netmask> 
(e.g.: setenv netmask


The Ethernet interface is activated and configured by systemd-network. The configuration file for the interface are located in /lib/systemd/network/ the configuration file can be altered to customize the default interface configuration. A documentation of the configuration files can be found here.

eth0 10-eth0.network

For a temporary static configuration the ip command can be used, below some useful ip commands are listed:

Activate a specific interface
e.g. eth0

ip link set eth0 up

Disable a specific interace
e.g. eth0

ip link set eth0 down

Show ip address for a specific interface
e.g. eth0

ip addr show eth0

Show statistic for a specific interface
e.g. eth0

ip -s link show eth0 

Set ip address for a specific interface
e.g. eth0

ip addr add dev eth0

Show statistic of all interfaces

ip -s link

Set default gateway for a specific interfaces
e.g. set gateway ip for eth0

ip route add default via dev eth0

If a DHCP server is available in the network environment the ip configuration can be received from it. To do so execute the udhcpc command, by default eth0 is used.
To configure another interface via dhcp the parameter -i followed by the interface name e.g. eth1 must be given.
e.g. eth1

udhcpc -i eth1 


The STKaRZG2x provides a HDMI interface, the interface is activated by default.


An overview of the onboard i2c devices is available here


Select i2c bus device

i2c dev 4,7

Show all devices connected to the i2c bus currently selected:

i2c probe


Detect all devices connected to a i2c bus:

i2cdetect 6,7,8


TQ offers an optional LVDS Display kit for the STKRZG2x. An LVDS Display can be used by setting the corresponding device tree in the U-Boot environment. To allow reusage, the support for each display is separated in a separate dtsi fragment.

To bring up the display the U-Boot environment has to be adapted accordingly.

1. Interrupt boot process in U-boot
2. Set U-Boot environment variable fdt_file a specific command has to be used for the differnt types of the TQMaRZG2x:

setenv fdt_file r8a774b1-tqmarzg2n_b-mbarzg2x-lvds-tm070jvhg33.dtb


setenv fdt_file r8a774a1-tqmarzg2m_aa-mbarzg2x-lvds-tm070jvhg33.dtb


setenv fdt_file r8a774e1-tqmarzg2h_c-mbarzg2x-lvds-tm070jvhg33.dtb

3. Save the envrionment by executing the saveenv command


To set the hardware clock to the actual time and date use the following commands:

date -s [YYYY.]MM.DD-hh:mm[:ss]
hwclock -w

Temperature Sensors

The STKaRZG2x has two temperature sensors, one is located on the TQMaRZG2x SOM and the other is locates on the MBaRZG2x baseboard.

Device I²C Address
TQMaRZG2x 0x1F
MBaRZG2x 0x1F

Read TQMaRZG2x Temperature Sensor

cat /sys/devices/platform/soc/e60b0000.i2c/i2c-7/7-001f/hwmon/hwmon0/temp1_input

Read MBaRZG2x Temperature Sensor

cat /sys/devices/platform/soc/e66d8000.i2c/i2c-4/4-001f/hwmon/hwmon1/temp1_input

Read CPU internal Temperature Sensor
The RZ/G“ CPU has an internal TMU that supports three thermal zones, all can be read by the commands below:

Thermal zone0

cat /sys/devices/virtual/thermal/thermal_zone0/temp

Thermal zone1

cat /sys/devices/virtual/thermal/thermal_zone1/temp

Thermal zone2

cat /sys/devices/virtual/thermal/thermal_zone2/temp
The temperature is shown in millidegrees Celsius.


With lsusb you can see all connected usb devices. To mount a partition of an usb stick you can excute mount /dev/<partition> <mount dir> (e.g. mount /dev/sdb1 /mnt). This will mount the first partition of sdb to /mnt. To unmount the device execute umount <mount dir> (e.g. umount /mnt).

User LED

The MBaRZG2x has three user controllable LEDs, the behavior of these LEDs can be selected by several triggers.

User LED Overview

Reference LED name color linux filesystem
V17 user_led_1 green /sys/class/leds/user_led_1
V16 user_led_2 green /sys/class/leds/user_led_2
V46 user_led_3 green /sys/class/leds/user_led_3

User LED Location

The user LED's are located in /sys/devices/platform/leds/leds/.
To change the behaviour a specific LED, the value in the file trigger must be overwritten.

The following values are valid:

For example set the trigger of user_led_1 to heartbeat

echo heartbeat > /sys/class/leds/user_led_1/trigger

SSH Connection

The file /etc/ssh/sshd_config is used to configure the SSH service. To be able to login with a password as user root change the following lines in the Authentication section

PermitRootLogin prohibit-password


PermitRootLogin yes 


#PasswordAuthentication yes


PasswordAuthentication yes

After altering the SSH configuration, the SSH service must be restarted to apply the new configuration:

systemctl restart sshd.socket

To setup a password for a user, execute the command passwd <username>, e.g. passwd root for the default user root, and set your password. Afterwards execute the login command to login the user with the new password.

  • Last modified: 2022/09/17 13:37