Linux Examples

System information

uname -a
cat /proc/cpuinfo
cat /proc/meminfo
lsblk
df -h
dmesg

After inserting a card:

lsblk
dmesg | tail -n 30

Manual mount example:

mkdir -p /mnt/tf
mount /dev/mmcblk1p1 /mnt/tf
ls -al /mnt/tf

Use the device name reported by lsblk on the actual system.

mkdir -p /mnt/udisk
lsblk
mount /dev/sda1 /mnt/udisk
ls -al /mnt/udisk

aplay -l
aplay test.wav

Direct MP3 playback depends on the codecs and player packages included in the root file system. aplay natively handles WAV/PCM audio.

ip link show
ip addr show eth0
ip route
ethtool eth0
ping -c 4 <gateway>

stty -F /dev/ttyS1 115200 cs8 -cstopb -parenb -ixon -ixoff
cat /dev/ttyS1
echo "I527BV3 UART test" > /dev/ttyS1

Adjust the device node and pin multiplexing according to the device tree.

cat /sys/kernel/debug/gpio
cat /proc/interrupts

On newer kernels, prefer the GPIO character-device interface and libgpiod tools.