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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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0answers
20 views

Got problem with dot matrix (MAX7219 FC16 module)

I am doing a project about notice board using led dot matrix display (MAX7219 FC16 module). the problem is: After I sent a message via webserver, only a text message will appear on the led dot ...
1
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1answer
50 views

5 switches, 5 leds, 5 tones, in an Array

The idea is when a switch is pushed, the corresponding tone will be played as well as lighting up the corresponding LED. I have the circuit set up to where each array matches another, for example ...
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0answers
26 views

FastLED fill_rainbow - Unexpected red pixel

I'm using FastLEDs builtin fill_rainbow function for generating a rainbow spectrum on an LED strip. The issue is, I get a random red pixel midway through the yellow region. I've tried it on 3 ...
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1answer
46 views

Dimming multiple leds with pot meter [closed]

I'm working on a small project. I have 13 leds which need to be controlled individually (turn on or turn off); Since I don't have 13 pwm pins I used a potentiometer to change the brightness. This ...
1
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0answers
19 views

TLC5917 SPI Speeds

I am attempting to use 3 x TLC5917 chips to drive a row of LEDs in PWM. The LEDs share a common anode being powered through a transistor, with each LEDs cathode going to pins on the TLC5917 Chips. ...
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4answers
50 views

help with a loop

I recently got into programing and I'm making an alarm. I cant figure out how to make a buzzer loop. I have two blinking LED's and two fading ones. Now I plan to have sound and it won't work. It only ...
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2answers
63 views

How can you have two blinking leds and a fading one

I am trying to make a alarm and I have two blinking leds (red and blue). They work fine but I want two more that fade in and out. I have a buzzer on it too. I am very new to programming. By the way, ...
2
votes
2answers
52 views

Using two sensors with delay concurrently

I want to use an ultra-sonic sensor and the led concurrently. I want the led to blink every 0.2 seconds and the ultra-sonic to measure distance without regard to the blinking. The problem is I have ...
1
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1answer
42 views

Midi controlled LED by USB [closed]

I am trying to create something that will allow me to control an individually adressable LED strip using an electric piano using its midi output. Some things to note: The piano can output midi ...
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1answer
32 views

Adjustable temperature [closed]

How can I make a project where I can adjust a temperature with buttons and a display and if the temperature is higher than that I set, a led turn on ?
1
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1answer
48 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
votes
1answer
83 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 ...
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1answer
34 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: ...
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1answer
76 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 ...
0
votes
1answer
35 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 ...
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0answers
58 views

Smooth LED wave algorithm

I would like to make a smooth wave algorithm of a single color as a blinker for my electric skateboard. Specifically, I have 7 individually-addressable RGB pixels that need to be different shades of ...
1
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1answer
41 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
vote
1answer
34 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
83 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
24 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 ...
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0answers
31 views

WS2812B and APA106

So ive used the WS2812B before for a propeller clock but now i want to use Apa106 and im not sure about how frequencies of the board and led correlate so in the answer of if i can use the apa106 led ...
0
votes
1answer
39 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
45 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 ...
0
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0answers
18 views

arduino on off fade - single button [duplicate]

I am trying to create a lighting circuit using LED strips. I want a single button to control the lights i.e. push on, push off, press and hold to cycle through dimming. I can get it to dim using a ...
0
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0answers
29 views

RGB LED colour transitions with accelerometer

I try to convert an accelerometer's upper hemisphere x and y rotations - meaning clamping output only to z positive orientations - into two pre-defined colour transitions of an RGB LED, where x and y ...
0
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0answers
29 views

Flicker LEDs from Arduino with precise square wave?

I need some advice regarding an Arduino setup I am currently working on. My aim: I have a set of 6 high power LEDs (http://www.roithner-laser.com/datasheets/led_highsingle/apg2c3-530.pdf) that I need ...
2
votes
2answers
383 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
vote
2answers
49 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
30 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 ...
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0answers
53 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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votes
1answer
48 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
75 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
42 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
57 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 ...
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3answers
34 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
131 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 ...
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1answer
23 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
84 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 ...
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2answers
73 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
35 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 ...
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1answer
37 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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votes
1answer
113 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 ...
-1
votes
1answer
45 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
74 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
47 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
vote
1answer
45 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
vote
1answer
48 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 ...
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votes
1answer
46 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
54 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 ...
-1
votes
1answer
49 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() { ...