CLI control of LED on mt300n

alzhao · 2018-08-12T01:16:41.225Z

Did you changed the firmware to a customized firmware? These LEDs names seems not bind to the physical LEDs.

There should only be three LEDs.
gl-mt300n:wlan/
gl-mt300n:lan
gl-mt300n:wan

kyson-lok · 2018-08-12T04:09:24.565Z

Nope, the color of the led isn’t configurable. You only can turn it on or turn it off. Those directory are located in /sys/class/led.

slowden · 2018-08-12T17:31:38.077Z

alzhao, the firmware was updated yes.
I posted the version in the first msg. If I recall, the /etc/config/system file was changed a little from factory. In the original, there is only mention of one.
config led ‘led_wifi_led’
Do I just need to put the old one back in and rebuild?
What else could I provide to help?

kyson-lok, I thought one of the LEDs is red which is the one I wanted to use.

alzhao · 2018-08-13T15:52:56.996Z

You may try the latest openwrt. I think openwrt standard the LEDs names to gl-mt300n:green:wan etc.

LED names is a little mess so if you have your own firmware.

So try latest openwrt or GL stock firmware for LED configurations. Cannot change LED color.

Don’t use usbpow because it is not LED. It is used to control the power of USB port.

slowden · 2018-08-13T22:31:27.578Z

ok but I am using my own /files directory. What must I leave that is factory in order to have the LEDs working as they should be? Not sure what I’ve removed that would cause this.

slowden · 2018-08-15T18:01:49.427Z

For future reference since no one seemed to have the correct answer, all I needed to do was to install kmod-leds-gpio kmod-ledtrig-usbdev in my build. Not sure if I need both but one or both allow me to control the LED.

Also, yes, there is a RED led, it is the WLAN.

Now this works.
echo 1 > /sys/class/leds/gl-mt300n:wlan/brightness
echo 0 > /sys/class/leds/gl-mt300n:wlan/brightness

With the above, I can turn it on and off but how can i make it flash also for example? Any other controls?

Johnex · 2018-08-15T19:38:50.076Z

To make it flash you add a delay between on and off

slowden · 2018-08-15T19:56:58.293Z

I’m not sure about that. I’ve read that there is something else, using the kmod-ledtrig-timer if I understand correctly. However, I cannot find a way to send the LED a command to do anything but go on and off.

Johnex · 2018-08-15T21:55:30.372Z

kmod-ledtrig-gpio
kmod-ledtrig-heartbeat
kmod-ledtrig-morse
kmod-ledtrig-oneshot
kmod-ledtrig-timer
kmod-ledtrig-transient

are some interesting packages you can try.

Morse and heartbeat are basically just turning the LED’s on and off and predefined intervals, which you can do using sleep in a bash script with the commands above for on and off so…

You can either write your own bash script to do what you want, or make a c++ program and compile it for more advanced things.

This basically what the GL UI is doing for the reset blinking and other blinking apart from the automatic from OpenWRT (which is probably also just calling the LED’s to be on or off).

slowden · 2018-08-15T22:06:45.352Z

Thanks for the input.
I can see how the echo command is being used to turn something on and off but the next trick I’d like to see is how to make the LED blink at a certain rate without using a script to turn it on and off repeatedly. Meaning, one command to start the LED flashing at a s certain rate, one more command to stop it or change it to another rate.

From what I have read, the kmod-ledtrig-timer is the package I need to do blinking LEDs.

I am not a programmer so am trying to avoid writing a script unless there is something very simple to be found on the Internet somewhere.

I find this on the openwrt site but no idea how to use it.

opkg install kmod-ledtrig-timer

Name Type Required Default Description
default integer no 0 LED state before trigger: 0 means OFF and 1 means ON
delayoff integer yes (none) How long (in milliseconds) the LED should be off.
delayon integer yes (none) How long (in milliseconds) the LED should be on.
sysfs string yes (none) LED device name
trigger string yes (none) timer

Johnex · 2018-08-15T22:11:51.457Z

If you mean this page:

OpenWrt Wiki – 17 Oct 16

LED Configuration

LED Configuration The LED configuration is located in system uci subsystem, and written in the /etc/config/system file. Basic led configuration is available via LuCI on the System > LED Configuration page. Led section The led section contains...

Then it is at the bottom.
You edit the /etc/config/system file and set the options you need.

config 'led'
	option 'sysfs'		'gl-mt300n:wlan'
	option 'trigger'	'timer'
	option 'delayon'	'500'
	option 'delayoff'	'500'

try that

Johnex · 2018-08-15T22:15:49.586Z

How to set it on the fly, well you need to follow these sets of commands:

https://wiki.teltonika.lt/index.php?title=UCI_command_usage¨

Something like this:

uci set system.led.trigger='default-on'
uci system commit

Have fun

kyson-lok · 2018-08-15T22:56:31.942Z

oops! It is easy to control led flash.

echo timer >  /sys/class/leds/gl-mt300n:wlan/trigger
cat /sys/class/leds/gl-mt300n:wlan/delay_off
cat /sys/class/leds/gl-mt300n:wlan/delay_on

Changing delay_off and delay_on to control flashing frequency.

slowden · 2018-08-15T23:14:58.878Z

I am able to make the wlan LED flash but only at one rate.

echo “none” > /sys/class/leds/gl-mt300n:wlan/trigger
echo “timer” > /sys/class/leds/gl-mt300n:wlan/trigger

Then back to ‘none’ to stop it but that’s not what I am looking for. I want to flash the LED at different speeds, have it remain flashing until I stop it using ‘none’ again, for example.

I’ll try your delay suggestion next :).

slowden · 2018-08-15T23:20:44.751Z

Now I am seeing what you mean.
Changing the delay is all I need to do. I don’t need to have a script turning it on and over repeatedly.

Send the ‘timer’ to the trigger file then the following to set the rate.

echo 1 /sys/class/leds/gl-mt300n:wlan/delay_on
echo 128 /sys/class/leds/gl-mt300n:wlan/delay_off

1 and 128 seems to be the max rate.

slowden · 2018-08-15T23:30:45.641Z

This is exactly what I was interested in, something that doesn’t require a bunch of programming, nice and simple.

For anyone that finds this.

Disable timer mode
echo “none” > /sys/class/leds/gl-mt300n:wlan/trigger

Enable timer mode
echo “timer” > /sys/class/leds/gl-mt300n:wlan/trigger

Set on/off flash rate that you would like.
echo 1 > /sys/class/leds/gl-mt300n:wlan/delay_on
echo 255 > /sys/class/leds/gl-mt300n:wlan/delay_off

Thank you for your help everyone. Hope someone that needs this will find it useful.

Johnex · 2018-08-16T00:29:32.471Z

You can check this:

OpenWrt Wiki – 10 Jan 15

Signal strength LED meter

Signal strength LED meter Sometimes you may need a simple indicator to know if the link has a good signal strength. Or for moving an antenna to catch the remote AP. Using leds is the more simple aproach. Scripts By blinking one led This script...

And the delay is an integer, so max is 2147483647. You won’t have much use then a few seconds, but you can set longer. They use 2 seconds in the example above, 2000ms.

slowden · 2018-08-16T01:04:27.406Z

Yes, I just realized this :).
I thought the limit was 1-255 but now I see there is more.
Now I’m trying to figure out how to change the brightness. Maybe the LED script has to be restarted for that since it doesn’t work like the others.

slowden · 2018-08-16T12:34:26.572Z

There is one interesting problem. I have not confirmed when/what causes this but when dealing with the files directly, meaning using echo to send into delay_on/off for example, the files eventually disappear. I have tested this on both tp-link and glinet to be true so far.

No idea what condition causes this to happen and only a reboot resets this. I’ll try restarting the led program next time.

slowden · 2018-08-16T12:40:49.548Z

Found the condition. When I sent a reset to the trigger file
echo “none” > /sys/class/leds/gl-mt300n:wlan/trigger

that removes the delay files.