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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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How do I detect if my iOS device has an LED light or not?

How do I detect if my iOS device has an LED light or not? I am trying to see the difference between an iPad 2 (front and back camera) and an iPhone 4 (front, back + LED light)
Ethan Allen
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Control LED brightness by using MCP3002 Analog to Digital Converter

I'm trying to control a list of PWMLED brightness by using MCP3002 ADC and Potentiometer. My issue is when I run my script everything is functioning as expected, except the potentiometer that is connected to MCP3002 ADC, it won't adjust the…
MrYosuko
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dumb question: Is there a way to make a color pattern repeat every X number of LEDs? Or do I have to write out the pattern for each LED in the strip?

I have a strip of 288 addressable LEDs and it is broken up into segments of 12 LEDs each. I have already written a bunch of code for colors and patterns designed for just one segment. The single colors were easy enough to adjust to fill all of the…
Z B
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How can I make an LED blink every n seconds without developing a lag?

I'm using an Arduino Uno to control LED. I want the LED to turn on every m seconds and remain ON for n seconds. I've tried this code using the delay() function (by adding delays after LED is turned ON and OFF) and also using the millis() function…
Severus
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Turn on vibration on Android by terminal command

Since long I am modifying Android kernels, but now I am stuck to find prompt while starting the Android. I am adding recovery inside the kernel image. For this there will be a prompt like vibration, LED or flash light for entering the recovery as…
Abuzar Shaheen
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USB drive LED flash

I was recently reading about the Arduino's Hello World application, and I thought to myself, "I wonder if I can do that with hardware that I have right now." Since I don't have an Arduino, I grabbed a usb flash drive that I had laying around and…
troyal
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Generating pure colors of equal brightness (for display on LEDs)

I have some RGB LEDs, and I want to have them display random colors. My first approach was to pick a random hue h from 0-360, create an HSV color of the form (h, 1, 1), and then convert from HSV to RGB using the algorithm given on Wikipedia. This…
user31708
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Python - Control Led using php

I would like to control my led lighting through webpage. I follow a YouTube tutorial, it works perfectly for pinon.php and pinoff.php. However, it does not work for control.php, anybody knows the reason? pinon.php
aaa
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Write data to SSD1306 via I2C

I'm using an SSD1306 OLED and have a question about it. When writing data to its buffer via I2C, some libraries write 16 bytes every time. For example: void SSD1306::sendFramebuffer(const uint8_t *buffer) { // Set Column Address (0x00 - 0x7F) …
mmmmar
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Serial monitor constantly say 0 when using arduino and sound sensor

I am having trouble with the arduino sound sensor and LEDs. I keep on getting the value of 0 in my serial monitor, the same thing happens with another sound sensor that I have. I am currently trying to make it light up the LEDs based on the sound…
Jonathan Weaver
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Arduino PWM fading led with avra

I'm writing Arduino UNO (=ATMega328P-PU) programs in assembly to save memory, so I use avra.exe (same as atmel studio's avrasm32) to compile and avrdude to upload, and simple programs like blinking run fine. But now i tried to half-bright a LED with…
Frazzo
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8051 assembly button click

I can't seem to find an answer for this question. One LED is connected to port P2.4, and one button connected port P1.7. We have COUNT variable, and we increment it each time the button is clicked. So if we press the button 5 times led is on, if we…
Hüseyin Aslan
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Python GPIO triggering LED with Pushbutton

I am trying to control and LED on an Raspberry Pi. I want the LED to light up when I push a button, and maintain that state until I push the button again. I have implemented the code below and it works quite fine. However, I am getting problems…
OYPS
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PIC16F883 Led Blink

I need to program a PIC16F883 to blink / light up LED's at the same time. The oscillator is running at 3,2768, and I'm using TIMER0 to help me with the timing. Right now, I have a prescaler set to 1:256, so I get an interrupt every 50ms, and I have…
Emil Wismann Kirkebæk-Jensen
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How can I trigger a series of LED events when a switch is HIGH, and how can I stop them whenever the switch is LOW?

I am trying to make this thing where every time a micro limit switch is HIGH (pressed), it starts this process that turns on a red LED for fifty seconds, then blinks the LED for about ten seconds, and then finally turns off the red, and turns on a…
bennyscot27
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