Turn On/Off Keyboard LEDs via commandline

xset led 3
Usefull as a light blink to remember events, mails, intrusions, etc... yet another output Since nobody ever uses the scroll lock function... Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick ) xset led 3 turns on the third led, ie, Scroll lock xset -led 3 turns it off xset led 1 turns on Numerical Lock led ( doesn t work on all computer ) xset led 2 turns on Caps Lock led ( idem ) Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)

By: m33600
2009-10-23 00:25:56

What Others Think

DaveQB · 638 weeks and 5 days ago
Any CLI ascii to morse translators around?
rbossy · 638 weeks and 1 day ago
this is what I call an idea!!!
m33600 · 638 weeks ago
Try this: http://freshmeat.net/projects/morse2led/ (it's in the AUR if you have Arch Linux)
matthewbauer · 637 weeks and 1 day ago
I found that setleds worked better. Usage: setleds +num < /dev/tty7
matthewbauer · 637 weeks ago
Happy Xmes! while true; do setleds -D -num < /dev/tty7; sleep 3; setleds -D +num < /dev/tty; done
Heoa · 630 weeks and 1 day ago
err while true; do setleds -D -num < /dev/tty7; sleep 3; setleds -D +num < /dev/tty; sleep 3; done
Heoa · 630 weeks and 1 day ago
Hmmm, interesting. I was experimenting and attempted an xset led 4. It turned on my caps lock and then one second later began sending endless returns. No matter what terminal I clicked on it kept sending returns making the desktop unusable. Found if I unplugged the keyboard and plugged it back in it reset. (Using a Logitech G110 Keyboard.)
john6of6 · 146 weeks ago
This hack sounds so cool but as I am not a Linux user so I am unable to understand this properly, Here you follow street lights Please make a video tutorial related to your topic. Hope to see this soon. Thanks anyways.
CrestLED1 · 32 weeks ago
This hack sounds so cool street lights
CrestLED1 · 32 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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