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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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Detect if hard disk is being accessed or not

I am trying to make a very simple hard disk access monitor to work like those embedded LEDs that blink according to drive usage. That LED REALLY helps me, but the laptop I am using does not have it. =[ So, I've made a simple tray icon application,…
LuckyScooby
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Arduino (processing) Library in Netbeans and control

I am trying to control 4 LEDs and getting analog input from 4 contacts. The program is written in java, so to gain acces to the functions of arduino, such as AnalogRead() and setting an LED to high or low, would importing the processing library let…
Casper Marcussen
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Send long array to arduino over serial from processing

So i build an 24x16 (hight of 16, length of 24) LED matrix and am using an Arduino Uno to control it. It is only a one color matrix and i am using an array to store all of the bits of data. This is an example of how i am storing the data on the…
user3399652
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A delay of a Few seconds when trying to power on Led flash

Im trying to power on the led flash, but the led flash powers on after a delay of a few seconds. I have a built in torch in my phone, and when I click it it the flash turns on immediately. Whats the problem here? Heres my code: private void…
mn6vdv23g
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Android: LED doesn't turn on/off

I'm trying to write a little Android widget with a button that turns the camera flashlight on/off. I know, there a thousands of it out there, but I want to learn Android (and little steps seem to be the best way). Now I've read the official…
roecket
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How can I switch On / Off LED Camera Flash on Windows 8 tablets (such as ATIV Smart PC)

I can't find a code to control windows 8 tablets camera flash. Can anyone help me get it?
Abdulla Eqab
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LEDs supported on the android device

Is there a way to know the number of LEDs an android device supports . For eg certain device support notification and charging LEDs and some devices support only charging LEDs . Is there a way for an app to know the number of LEDs present in the…
sim
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Arduino sketch does not work, the pins do not output anything

I have an Arduino Uno, and I'm trying to control my s107g rc helicopter with it. This code was available for download along with a few Youtube videos showing tests of it. So when I tried it with the IR led it didn't work. I tested it with normal…
Matthew Brand
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Permanently enable and disable blinking LED notification light in android programmatically

I have been looking for the ability to disable and enable the LED notification light through code. I saw this thread Disable/enable notification led, but it is quite old and I was wondering if the new API versions has some support for turning it off…
user1431748
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How to change LED trigger?

I have register in BSP's the LED: static struct gpio_led ic_leds[] = { { .name = "led1:green", .gpio = USER_LED, .default_trigger = "heartbeat", …
swmail
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LED Matrix using AVR Controller

I have created a 8x8 LED Matrix that is controlled by a mircocontroller (specifically Atmega8), an 8-bit shift register (HEF4794), and a driver array (MIC2981). The problem I having is that the pattern that is supposed to be displayed is not…
Scott Gardner
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Arduino RGB LED Clear

I have an RGB LED and have pins to 9, 10, 11 and a pin to ground. Resistors have been provided for R, G, and B. When I do: analogWrite(r, 255); // I see a red color analogWrite(g, 0); analogWrite(b, 0); analogWrite(r, 0); analogWrite(g,…
A.W.
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Built-in led won't turn on STM32F303RE Nucleo board

I am trying to turn the led (LD2 in schematic) inside the nucleo board on using only registers with the STM32CubeIDE. The user manual states the following addresses for the clock, mode and data registers: Led pin: PA5 Address of the Clock control…
CKiamy
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Weird output for RGB

I am trying to manage some LED strips with my mobile device using bluetooth + Adafruit NeoPixel. I almost had the sketch finished but I have found the numbers for RGB are not appearing as I expected and I cannot find what I am doing wrong. Imagine…
UnitedFioreMages
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How to hook up LED lights in C++ without microcontroller?

I want to light up/off LEDs without a microcontroller. I'm looking to control the LEDs by writing a C++ program. but the problem im having is hooking them up is there a free way to do !!!! I'm using Windows XP if that is relevant. I have LEDs but I…
H4cKL0rD
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