Application Notes Linux (with sample terminal commands)

Owned by Albinleo Velappan (Deactivated)
Last updated: 23. Jan 2023 by Sven Hillger
2 min read

Howto... (unordered)

Set Backlight Brightness

$ echo X > /sys/class/backlight/backlight/brightness

X: Value 0..100

List Block Devices (incl. mountpoint)

$ lsblk

Example output:

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 1 14.6G 0 disk `-sda1 8:1 1 14.6G 0 part /run/media/sda1 mmcblk0 179:0 0 7.1G 0 disk |-mmcblk0p1 179:1 0 500M 0 part /run/media/mmcblk0p1 `-mmcblk0p2 179:2 0 6.6G 0 part / mmcblk0boot0 179:32 0 4M 1 disk mmcblk0boot1 179:64 0 4M 1 disk mmcblk0rpmb 179:96 0 4M 0 disk

List USB Devices

See 'lsusb –help' for options; i.e. -v for verbose output.

List PCIe Devices

See 'lspci –help' for options; i.e. -v for verbose output.

Change Terminal Output Length

Useful to view logs or enter commands in terminal window without having the line-wrap/cut after 80 characters.
i.e. set to 1000 characters:

i.e. check window-size of serial-terminal:

Using Serial (tty) in Linux

To identify usably serial ports use:

Configuration and terminals:

  • setserial

  • cu; i.e. cu -l /dev/ttyS0 -s 115200

  • screen

  • minicom

  • putty

  • tip

When accessing a serial port i.e. /dev/ttyS0 or /dev/ttyUSB0 (FTDI) , you may get a /dev/ttyS0: Permission denied error.
A way around this is to add yourself to the tty and dialout group:

You will need to properly logout and login again for changes to take effect.

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