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Questions tagged [led]

A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices.

A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices, like mobile phones or micro-controller boards.

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Can I change the LED intensity of an Android device?

Is there a way to set the LED intensity that I desire? I know that to turn on the LED I use: p.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH); mycam.setParameters(p); But this code just turns on the LED. But is there a way to set…
Buda Gavril
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LED flashlight on Galaxy Nexus controllable by what API?

So many LED flashlight API questions for Android. I'm afraid to ask yet another, but here goes.. Using the tried and true FLASH_MODE_TORCH I am able to achieve satisfaction with my Samsung Galaxy SII and get the LED flash turned on. On my friend's…
Malachi
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Turn off leds of Raspberry Pi

I would like to turn off the leds of my Raspberry Pi. I tried modifying the file echo none >/sys/class/leds/led0/trigger but nothing changed. Is this possible?
Mauro Midolo
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Individual Access of Camera LED Lights of iPhone 5s

I'm coding for the iPhone 5s and it now has two LED lights for the rear camera. I don't know the official LED color names, but one LED is white and the other LED is yellowish. Apple refers to this as "True Tone". I'm trying to access these camera…
JimVision
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How to use camera flash/led as torch on a Samsung Galaxy Tab?

I'm facing to a problem with a Samsung Galaxy Tab. I want to use the camera flash as torch. Does anyone know how to enable it ? Hereby a code that works to enable/disable the camera flash on a HTC Desire but fails on Samsung Galaxy…
Sly
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Can I detect the presence/absence of 'LED notification' on an Android device?

Background: I have an app with notifications and I want to support LED notifications (and it's working perfectly). In my preferences, I allow the user to customize the LED notifications. Problem: I don't want to show the LED customization options if…
copolii
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Can the Android handset LED be manipulated without using a Notification object?

I want to control the LED on an Android device with more control than is offered by the Notification class. Notifications allow you to change the rate of flashing; e.g. 300 milliseconds on, 1000 milliseconds off, but that's it. Essentially, I would…
Omniwombat
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Control Android LED from shell

I have seen several questions (and blog posts, elsewhere) with Java code for controlling the notification LED on an Android device. That's not what I'm looking for. I'm wondering if there is any way to access the appropriate commands / controls /…
Vicki B
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How to control Computer RGB LEDs in Linux

Since I switched to a new AMD Ryzen system my computer lit-up. All new hardware components seem nowadays to have such fancy(?) RGB-LEDs built in (even in memory modules, even the stock CPU-cooler from AMD). I don't like that and want to switch all…
gue
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Fading Arduino RGB LED from one color to the other?

I've currently managed to get my LED to cycle through eight colors that I've selected. Everything is working correctly, except that I want to go for a more natural feel, and would like to fade / transition from one color to the next, instead of…
KingPolygon
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LED Flashlight does not work on Samsung Galaxy Nexus

I've got the following problem: My Flashlight app works fine on my Samsung Galaxy S2 but unfortunately not on the Samsung Galaxy Nexus (problem: flashlight ignores the button-click -> no reaction, no light, no crash, no exception). I've read "LED…
CarpeTempus_
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Android Notification LED doesn't use my Color

I'm trying to use a Notification that also uses the Notification LED on my S3, but for some reason the color will always be blue (I guess it's the default?). I tried to use different colors but nothing changes. Other apps (like Whatsapp, Gmail and…
Luc Kolen
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Camera.Parameters.FLASH_MODE_TORCH replacement for Android 2.1

I am trying to write an app that requires the LED flash to go into torch mode. The problem is, Android 2.1 does not support this mode and therefore I cannot support the platform yet. Wouldn't be an issue, but I am writing it for my fiance and her…
smccloud
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How to detect multiple faces using opencv in order to generate an output of flickering LED lights

I am fairly new at using processing and OpenCV, so please bear with me. I have posted my question on both StackOverflow and on the processing forum to reach a wider audience and find a solution -- so apologies if this looks as if I am carelessly…
Gaby Rock
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Nexus 5 (4.4.2) Flashlight LED not turning on

I wrote a simple flashlight app that I've tested on an HTC Sensation, Nexus 7, HTC One, Moto X, Galaxy S3, Galaxy S4, and a Nexus 5. The only one that it doesn't work on is the Nexus 5. It doesn't throw an exception so finding out what's wrong is…
Zeek Aran
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