Embedded module TQMa65xx - YOCTO Linux BSP documentation


CAN

The MBa65xx provides the CAN interfaces CAN0 and CAN1.

CAN configuration

DIP switches SW2 and SW3 are used to configure the CAN interfaces CAN0 and CAN1.

Function SWx-1 SWx-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.

CAN FD 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

Ethernet

The STKa65xx Starterkit provides seven Gigabit Ethernet interfaces.

U-Boot

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 192.168.100.111)
setenv netmask <netmask> 
(e.g.: setenv netmask 255.255.255.0)

Linux

The Ethernet interface is activated and configured by systemd-network. The configuration file for the eth0 interface is located in /lib/systemd/network/ these 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 192.168.1.100/24 dev eth0


Show statistic of all interfaces

ip -s link


Set default gateway for a specific interfaces
e.g. set gateway ip 192.168.1.1 for eth0

ip route add default via 192.168.1.1 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 

I2C

An overview of the onboard i2c devices is available here

U-Boot

Select i2c bus device

i2c dev 0

Show all devices connected to the i2c bus currently selected:

i2c probe

Linux

Detect all devices connected to a i2c bus:

i2cdetect 0

RTC

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 STKa65xx has one temperature sensors, located on the TQMa65xx SOM.

Device I²C Address
TQMa65xx 0x1F

Read TQMa65xx Temperature Sensor

cat /sys/devices/platform/bus@100000/bus@100000:bus@28380000/bus@100000:bus@28380000:bus@42040000/42120000.i2c/i2c-0/0-001f/hwmon/hwmon0/temp1_input

Read CPU internal Temperature Sensor
The AM65xx 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

USB

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 MBa65xx has two user controllable LEDs, the behavior of these LEDs can be selected by several triggers.

User LED Overview

Reference LED name color linux filesystem
V1 led0 blue /sys/class/leds/led1
V2 led1 blue /sys/class/leds/led2

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 led1 to heartbeat

echo heartbeat > /sys/class/leds/led1/trigger

  • Last modified: 2022/09/17 13:40