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Questions tagged [led]

An LED is a type of light source which is typically fairly small and has low power requirements.

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1answer
91 views

Arduino UNO LED half brightness when connected to digital GND but not analog [closed]

I am using an Arduino UNO. When lighting an LED with the switch button on a joystick module, I have two situations: If the LED's cathode is connected to GND on the digital pin side of the Uno, the ...
-1
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1answer
92 views

how to connect 100 Leds and Blink them on Arduino [closed]

I am planning to connect 100 LEDs to an arduino in a parallel circuit. The current limit exceed beyond the Arduino UNO board. In want to blink all 100 LEDs at same time. So how can I provide power ...
0
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1answer
40 views

LED on Arduino does not blink

I successful installed arduino, added me to uucp and lock and loaded cdc_acm module. I use Arduino Uno R3, so I also installed arduino-avr-core. I have Arduino on /dev/ttyUSB0. I configured with: ...
0
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1answer
1k views

FastLED - How to Control specific LEDs

I am fearly new to Arduino and FastLED. I found a nice Sketch which fits almost perfectly to my needs. Just one Problem: I dont want the Sketch to effect ALL LEDs in one color. I want some LEDs in ...
1
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1answer
103 views

Blynk app, DotStar bluetooth control code help

This is my setup: Arduino Mega; HM-10 bluetooth module (bought off ebay, so not sure if genuine but works); Adafruit Dotstar addressable LED strip; iOS Blynk app; Hardware-wise, everything is ...
1
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1answer
123 views

Flickering LED when servo moves

I just got to play around with Arduino lately so I'm really new on this stuff and sorry for the grammar error. I got a work where I need to turn the LED on all the time, my plan is to add a slow fade ...
1
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1answer
37 views

Arduino with 8 LEDs and a switch

I have an assignment wherein we have 8 LEDs connected to an Arduino Uno which has a switch. These LEDs light up according to the johnson counter but every time I turn the switch off it should reset ...
1
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2answers
90 views

arduino firmware

Hi I was wondering if there is any way to/ how I might go about solving the following. I am designing my own arduino board based on a mega32u4 chip and I want my arduino board to light up an ...
0
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1answer
46 views

Use IR remote with arduino

I would like to use the IR remote with Arduino to turn on a LED and turn off the same LED when I push on the remote. That is to say : If I push on 1 I would like the LED turn on If I push on 2 I ...
0
votes
1answer
56 views

What value of resistance to put between the output of a 74hc595 and the LEDs?

I'm going to start a project to make an array of LEDs using the shift registers 74HC595, I've seen many tutorials and it's not really difficult using the Arduino plataform. The situation is as ...
0
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1answer
316 views

Looking to blink entire led strip

I am fairly new to FASTLED programming and am looking to make my entire LED strip blink at the same time. Similar to the Example Sketch "Blink" however all 30 of my LEDS. I might just be having a ...
2
votes
2answers
388 views

How do I change the default LED pin for displaying uploading

I made a board for my project based on Arduino Pro Mini. The problem is, that I had to put the LED on pin 4 instead of pin 13. What setting do I have to change to make pin 4 the default one? Or do I ...
1
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2answers
56 views

Keeping track of multiple actions

I have a number of LED's connected to an Arduino which receives a JSON dict. The JSON dict determines which action the LED's follow (either a fade, a pulse, on, or off), but I'm having trouble ...
0
votes
1answer
44 views

How to stop extra LEDs from lighting in LED cube

So I build LED cubes and the way I have it programmed is I use an analog pin for the ground layers and set them to high when i want an led on that layer lit up. So lets say I wanted the following LEDs ...
1
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0answers
62 views

Do I need one N3904 for each LED?

I want to control 4 (or more) LEDs using the PWM output pins of my Arduino. Here is how I have it on a breadboard, and it's working for me. Question: Is this schematic inefficient? Are there any ...
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1answer
60 views

LED does not light when inserted into round Lilypad board [closed]

Title: LED does not light when inserted into round Lilypad board. very simple goal here: i want to plug in a blinking LED [or 10] into a round circuit board [then solder them], then power those LEDs. ...
0
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1answer
156 views

RX and TX pin in Arduino Uno

I have LED Cube Project, and I want to activate the LED with My Android apps (Bluetooth). The LED Cube used A0-A5 and D0-D13 Pins, and the Bluetooth need RX and TX (D0, D1). Where I can put the RX ...
3
votes
1answer
61 views

Timer interrupt triggers too often

The following question is based on the Arduino Pro Mini (8MHz, 3.3V) I'm in process of developing (yet another) LED strip driver shield. For that I wrote a simple control loop, that adjusts the ...
1
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1answer
130 views

Triggering both LED and buzzer [closed]

I am attempting to create a motion detector that triggers both a 12V LED and a piezo buzzer, but have read that you cannot use delay() with them both. How do I trigger the LED and the buzzer ...
1
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3answers
57 views

The Arduino IDE can’t find my Arduino Uno

My Arduino has all of its LEDs on. The Rx, Tx and L LEDs are all on and my computer can’t see it (it's an SMD edition).
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1answer
1k views

Control multiple LEDs with multiple buttons

Problem 1: LED1 needs to be on only when button1 is held down. Right now it takes several presses to turn on and off and stays on. Problem 1: LEDs 2,3,4 do not turn off with buttons 2,3,4. They are ...
0
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1answer
24 views

Variable that holds the users input doesn't empty itself, so the program only works once

This code seems to function, but only works once before I need to press the reset button. Otherwise, it repeats the same error message. It might have something to do with emptying the String variable. ...
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0answers
168 views

Output multiple arrays to single LED Strip

I'm currently working on a rather large LED display and am wondering if it's possible to output more than one CRGB LED array to a single pin (using offsets; I don't want to write different values to ...
0
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2answers
224 views

Random LEDs light up on 10 MAX7219 modules

I'm trying to create an IoT clock using 10 MAX7219 (Serially Interfaced, 8-Digit, LED Display Drivers) modules. I've created the following code: //clock.ino #define MODULES_X 5 #define MODULES_Y 2 #...
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0answers
36 views

Arduino Uno LED not working

so I'm new to all this Arduino stuff and have been trying to get into it, starting off with a simple project/test but have been having some issues. I followed the set up the book provides, and am ...
0
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1answer
38 views

Does blinking an LED with no resistor for a few seconds harm my Arduino?

I am new to Arduino and I just made my first LED blink. I connected the LED to ground and digital pin 13 without resistance (for only a few seconds). Does this harm my Arduino? Hilmi
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1answer
153 views

Traffic signal simulation: A minor doubt

I am trying to simulate a traffic signal with a provision of a pedestrian button, that when pressed, stops the traffic for a while. Here are the conditions I'm trying to meet, One green LED (on pin ...
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votes
1answer
54 views

How do I get LEDs to turn on according to a continuous Python input?

I'm trying to make a tuner. 3 LEDs are connected to the Arduino board, each one corresponding to one situation (too high, low or correct). Python handles the detecting of a note according to the mic ...
5
votes
3answers
78 views

How to improve response time of this sound operated LED?

I have written the following code for lighting an LED on a clap ( using sound sensor) that I have connected via a resistance of 330 OHM on pin number 4. However, when I clap once, close to the ...
0
votes
1answer
71 views

TLC5917 Electrical Characteristics

I am using an Arduino Uno to communicate over SPI to 3 cascaded TLC5917 chips corresponding to the Red, Green and Blue rows of an RGB LED Matrix. I am using direct output IO from the Arduino to power ...
1
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1answer
116 views

IR receiver starts giving nonsense readings in LED colour change setting

First of all, I'm very new to this so sorry if it's a dumb question. I have an IR module which I'm using to control an LED strip. I have set buttons 1–3 on the remote to select three basic static ...
1
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1answer
75 views

Relay Board making Output Signal Weak

I am using an Arduino Uno and Relay Shield (http://www.seeedstudio.com/blog/2013/02/28/shield-evolution-flexible-add-ons-for-arduino/relay-shield/), and using a code similar to the Teapot Demo, in ...
0
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1answer
128 views

Arduino Wall Wart and Relay Board Power Supply

I am relatively new to Arduino, and have been doing a project to trigger an LED/alarm when movement is detected to be over a certain threshold value. I am using an Arduino Uno, an LED/buzzer (https://...
1
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1answer
59 views

Why the LED freezes? when I am adding a delay?

I am new into arduino and stuff. So i was playing around with the pull up resistor. It worked fine but the problem rised when I used a delay to turn the led on for few seconds before it gets back to ...
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votes
1answer
58 views

I want a code for 6 LDR/LED pair

Each LDR is connected to one LED because I am doing a parking lot model. I have tried but with no luck. Help! int ledPin = 11; int sensorInput = A0; boolean ledIsOn = false; void setup() { ...
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2answers
599 views

How to control Neopixel LEDs in parallel?

Imagine a collection of LEDs (Neopixel or otherwise) labeled 2 through 12. There may be more than 11 LEDs, so repeat numberings are allowed. I want a simple way to control them from a single Arduino ...
0
votes
1answer
195 views

Breaking out of a while loop using IR remote for neopixel

I've been piecing together various lighting effects. I am wanting to have each lighting effect loop until another button is pressed to trigger another lighting effect. I've come to a bit of ...
0
votes
1answer
84 views

Turn on LEDS one after another

I am trying to turn on LEDs one after the other so that I can start at one end and slowly turn the LEDs until it reaches the middle of the strip. The code works coming from the end of the LED strip, ...
1
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1answer
212 views

Sending a character 'A' through blinking led

How do i code to send a character 'A' to the arduino through a blinking led? i am doing a project about data transmission. i really need help&some guide. Material used are arduino uno r3,...
0
votes
2answers
683 views

ESP8266 Led is not working

My led is not blinking, I have no idea why it's not working. I am running it on "generic esp8266 module" plate. /*Blink Turns an LED on for one second, then off for one second, repeatedly. ...
0
votes
0answers
98 views

FastLed code LEDs only displaying blue

I'm just starting out learning to code in Arduino, so I'm finding examples online and modifying them a bit. I found this bit of code online for pulsing LEDs. I tested it out and it worked fine to ...
0
votes
1answer
205 views

Binary addressing and coding to control a 96 input mux matrix

I’m trying to wrap my head around using binary addresses in a mux. Failing miserably. For the circuit I have six 16 channel analog multiplexers CD74HC4067 as slaves to an eight channel multiplexor ...
0
votes
1answer
694 views

Bluetooth a pushbutton from one arduino to another to turn on a LED

For a major project at school i need to get a bluetooth module to be able to communicate between two HC-05 modules as a master and slave. They need to be able to press a pushbutton on the slave and ...
1
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1answer
88 views

Small Baseball Scoreboard using 2 to 3 breadboards

I'm helping my son start an Arduino small baseball scoreboard (roughly 2 or 3 breadboards in size). Im thinking to use qty 2, 2 digit 7 segment LED's (score of each team), an LCD 1602 module (inning ...
0
votes
0answers
34 views

Use 1 resistor for multiple LEDs [duplicate]

Is this possible to use 1 resistor for the entire led circuit?
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votes
1answer
42 views

Making a distance sensor for human interaction [closed]

I want to make a sensor that senses a person between 1.5 m and 0.2 m, connected to an LED that is on 100% at 0.2 m and 1% at 1.5 m and gradually scales. Is an ultrasonic sensor the best sensor to use ...
0
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1answer
137 views

How does Peggy2 drive rows with 74HC154 Decoder?

Trying to program Evil Mad Scientist's Peggy 2 board without their Library. The board drives a LED Matrix with Source 74HC154 Decoder Sink STP16CPSO5 LED Sink Driver Schematic What has me ...
0
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2answers
113 views

Comparing button presses to correct sequence

I am creating a memory game with the Arduino. It has four buttons, each for a different colored led. The leds will blink in a random sequence and either fail or add another light in the next sequence ...
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2answers
146 views

One of the LEDs on my Arduino is very dim

I made a vibration sensor using an Arduino. It is connected to an Android app. When the start button is pressed on the app, a red light LED turns on (stand by), and after 2 - 5 seconds, the red LED ...
0
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0answers
87 views

Lighting up long led strip no longer works when my code grows

I have a 144 LED strip - Adafruit NeoPixel Digital RGB LED Strip 144 LED, link here: https://www.adafruit.com/product/1507 If I create a simple project, eg turning pixels on off from the serial ...