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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
296 views

How do I connect a LED strip to a Multiwii SE 2.5?

https://www.m.nu/neopixel/mini-skinny-neopixel-digital-rgb-led-strip-60-led-m-black-pcb-1m I just purchased this led-strip that I plan to use with my Multiwii SE 2.5. I power the Multiwii itself ...
1
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3answers
562 views

NodeMCU NeoPixel

I am attempting to control a single NeoPixel with a NodeMCU, but I'm not having any luck. Even just loading the default Adafruit NeoPixel library sketch yields unsuccessful results. I've tested the ...
1
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2answers
130 views

Help What am I doing wrong? Matrix Led

I'm new and im trying out the Matrix LED heres my code #include <LedControl.h> LedControl lc = LedControl(12, 11, 10, 1); unsigned long delayime = 100; void setup() { lc.shutdown(0, false);...
3
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4answers
188 views

Is it possible to run two for loops separated?

I have three funtion which describe the brightness of three LEDs. I want the seconde loop run 1 second after the first one and the third 1 second after the second one. One loop needs approximately 5 ...
0
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1answer
382 views

Buzzing on computer speakers when LEDs are on

I have an Arduino Nano connected via USB to a Mac Mini. When the LEDs come on, an external speaker connected to the Mini starts to hum/buzz quite loudly. If the LEDs are turned off, the buzz stops. ...
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2answers
205 views

15x15x15 LED cube with thermal sensors

I'm trying to wrap my head around a public art project that I've recently received funding for, and I'm hoping that someone here can help me with a bit of guidance. The concept I'm working on is a ...
0
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2answers
69 views

time delayed LEDs

I have two LEDs an I want the first one getting linear brighter and the second one do the exact same thing just one ore two seconds later. When one LED has reached 100, it should getting darker until ...
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2answers
222 views

polynomial change of LED brightness arduino

I try to change the brightness of an LED following the formular in out1. I'm pretty sure that something is going wrong because it doesn't really change its brightness and it never stops lightening. ...
0
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1answer
108 views

Feasibility of project with 50 leds working independently

I don't have much knowledge in Arduino and I'm about to start a new project which I believe can be done with it. There will be 50 boxes with a led in top of each one. The user will type a number in ...
2
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1answer
205 views

Can I power my shift register with a 12V external power supply and connect only the data, strobe and clear pins to the Arduino digital pins?

I'm using a CD4094 shift register to power my LEDs along with a ULN2003A darlington transistor array. I want to hook up the LEDs to an external power supply of 12V (common anode). The cathodes of ...
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2answers
6k views

Arduino code to control 4 led's from 4 buttons

This is my very first arduino sketch and it's causing me a bit of a headache. Sounds so simple really all I want the sketch to do is digitalread from one of 4 digital input pins and then digitalwrite ...
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3answers
149 views

Two Arduinos get out of sync after a few seconds

I built a small PCB that has some LEDs (bare NeoPixel 5050) and an IR receiver on it. The microcontroller is an ATtiny85, and the PCB is powered by a LiPoly battery (3.7V). The circuit normally stays ...
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1answer
76 views

Why is 8x8 matrix pins do not correspond to rows and columns order?

It would be easier to program led matrix if 1-8 pins corresponded to 1-8 rows and 9-16 pins corresponded to 1-8 columns. Instead there is the following arrangement: Why is it made like this?
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2answers
101 views

Getting more current through an LED array

I have an Arduino Uno controlling an array of 24 LEDs (datasheet). I understand these LEDs are ultraviolet and have a forward current of 0.5A. My power source (12V 2A) is wired to a switch which is ...
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1answer
240 views

Some questions about a RGB LED Strip project that Im planning to do

Good day all So Im in the planning and research phase of a new project that I want to start for my car. I want to control a bunch of RGB LED strips independently from each other via a micro ...
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3answers
554 views

Turning on many (30) leds arduino mega

I´m new working with Arduino. Right now I have a project thar requires to turn on 30 LEDs at the same time with an Arduino Mega. The problem is that it would exceed the max current that the chip can ...
0
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1answer
61 views

Powering leds from arduino with adapter

Sorry for having (again) a beginners question, but I was wondering something. If I would want to drive like 20-30 LEDs from an Arduino (Uno), and I want to use an external adapter (12V, 1A), going ...
2
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3answers
1k views

Button and switch to turn on and off LED and changing after time

I have system connected to an Arduino Uno where I want to read whether the switch is open or closed. Based on if the switch is open/closed, I want an LED light to turn on/off. When the switch is ...
1
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1answer
273 views

Decoupling cap for self-powered LED matrix and LED strip

Should I add a decoupling capacitor to my RGB 16x32 LED matrix powered directly via the 5V pin? When I display a spectrogram, the current load is fluctuating quickly in the 100-250 mA range (on ...
0
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1answer
756 views

LED sequence control by button [closed]

I want to make sequential LED by using arduino that controlled by button. If I press + button, LED will increase from L1 to (L1 and L2 is HIGH), then I press button again, L1, L2, and L3 will be HIGH....
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1answer
142 views

how to drive 500W of leds

I am currently developing a project that needs 9 led stripes, each led stripe has 5 meters, 300 leds, it consumes 60W per stripe in a total of 540W... This are the led stripes - 5M 12W/M 24V SMD 2835 ...
0
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1answer
388 views

Arduino Nano + (2* tlc5940) + 34 LEDs = Power Questions

This is an adapted layout for two tlc5940 hooked up to an Arduino nano. The original project can be found here. I am a little unsure about the capacitors and resistors as that project had it hooked up ...
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1answer
35 views

How can I add a LED to this build?

I recreated this project from Fritzing in my circuits.io project then on the arduino itself, it all works fine just how I wanted it. The concept behind it is: You plug it in and the time is set to ...
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2answers
200 views

How do I send all notifications from specific apps (like Skype or Facebook) to my Arduino through Wifi?

I am making a project that includes notifying a person through a specific colour on an LED strip. I need to find a way to send all notifications from a specific app to my Arduino through Wifi. It ...
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2answers
172 views

Controlling a LED array from Arduino NANO

I have a project Im currently busy with that I need a lot of help with. What I want to do i create a flat 8x12 grid of LEDs and be able to control each individual LED independently from the others. I ...
0
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2answers
82 views

Make lights come on and off depending on which button is pressed

Imagine a strip of LEDs with O being HIGH and X being LOW. X O X O X Now if I pressed the button below the second O and wanted it to switch the last two LEDs (4th one to LOW and 5th to HIGH or any ...
0
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1answer
282 views

Error compiling: expected unqualified id before token {

#include <LiquidCrystal.h> #define trigPin 12 // the trig pin to digital pin 12 #define echoPin 13 // the Echo pin to digital pin 13 #define led 8 #include <Servo.h&...
3
votes
1answer
281 views

Powering the attiny85 with a separate power source

I have an LED project for which i'm using a 9v power supply. For part of the project I'm using an off the shelf LED driver that is compatible with 9v however I have one LED component that I want to ...
1
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2answers
433 views

3x3 LED Matrix with less pins

I'm building an audio cable tester/soldering station. XLR cables have 3 pins and they can be wired in a few ways depending on what you want to do. The basic cable is connected 1 for 1 and I want to ...
0
votes
2answers
422 views

Press on pressure sensor once, turn on LED for 6 seconds

I am working on a project where I would like to press on a pressure sensor (0-1024) once and turn on the LED and turn off by itself after 6 seconds. I am quite new to arduino and I can't seem to ...
4
votes
2answers
462 views

Molex power with USB serial Communication from the same PSU

Before I begin I just want to apologize for my mediocre understanding of things electrical and arduino. I know there are a lot of topics similar to this but I'm confused by the term external PSU ...
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2answers
62 views

When a pushbutton and sensor are in a certain state, do something for a certain period of time (15 seconds)

I have a sketch that contains code for an analog input (FSR sensor), a pushbutton, and 6 blinking LEDs. Currently, the sketch is written to allow the LEDs to blink only when the button is pressed and ...
2
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2answers
3k views

Implement Visible Light communication using Arduino

I want to implement a simple VLC based communication system using two Arduinos and send messages/data/files between two PCs. For that I have a simple transmitter circuit with an LED on Tx side and a ...
0
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2answers
67 views

i am unable to make a correct program using the pushbutton to toggle LED on/off?

I want to toggle the the LED on on my first complete click(i.e. pushing and even releasing the pushbutton) and i want to make my LED off at my second click. This is the program :- int led = 13; int ...
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1answer
567 views

How to blink 2 led strips without delay

Hi all I use 2 sensors and 2 led strips. I want to let both led strips light up without interrupting each other while reading the different values from the inputs. But Arduino still pauses when one ...
0
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0answers
70 views

Using an Arduino Uno to program a PIC12F1571

I wanted to build my own version of the Pixie, an individually addressable LED. How do I upload code to the PIC12(L)F157X microcontroller? I think the code I want to program is this.
2
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1answer
102 views

Matching the blink of an LED to midi music

I have a function that plays a song and lights an LED corresponding to the note that is being played. when the same note is played consecutively(i.e E in bar 6) instead of the LED turning on and off ...
6
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1answer
174 views

Working with multiplexers for constant voltage output

I'm working on creating a circuit where I'm trying to have the ability to switch multiple strands of LED rope on and off at a time using an Arduino and a multiplexer. With my current configuration, ...
2
votes
2answers
420 views

POV using ATmega328 powered with cr2032 cell

I am planning to make a POV (persistence of vision) display using ATmega328 with 5 red LEDs for display. Below are my aims: I want to power it with cr2032 coin cell, so power consumption has to be ...
3
votes
1answer
279 views

Arduino leave PWM on

I am doing an aquarium light sunrise/sunset. Till now programming wise I only did the sunrise. After running the code the light starts to rise up fine, than at full brightness, it turns off. I want ...
6
votes
2answers
6k views

Using a transistor to get 100mA on a IR led

What i saw is that the led use 1.3V on 100mA with a 1:10 Cycle (100ms). Im currently at 30mA using only a 100 resistor, but the range of the led is 20cm at max, i want to get at least 2 meters. Since ...
3
votes
1answer
55 views

What is the correct way to create large project files?

I am currently working on a 10x10 RGB LED screen (using Neopixels from Adafruit) and my project files are starting to get rather large. I have several different devices used in this project: The LED ...
1
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1answer
961 views

LED fade with LDR sensor depending on the light

I need help on a project. I just started to experiment with arduino 2 weeks ago and I am building a lamp that react to movement and interactions. So the idea is; when there is nobody in the room, the ...
0
votes
0answers
8k views

How to read the received SMS from GSM and do actions accordingy?

Here I am using AT commands to receive SMS and I am trying to read the received message. I want to switch on the builtin LED of the Arduino board but I am not able to store the received message in a ...
0
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1answer
793 views

How to drive a strip of 12 V no-addressable LEDs?

I recently bought this LED Strip. I got the 5M 3528 300LEDs SMD RGB Non-waterproof ones. However, I am not sure how to use them. On the strip there is four wires. I have tried supplying power to the ...
0
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1answer
60 views

Could someone help me with an Arduino Uno program? [closed]

I am thinking to do a gas leakage and fire detector using a GSM module in my home. I got all the contents like an Arduino Uno, MQ22 gas sensor, LM 35 heat sensor and GSM module SIM800L to send SMS and ...
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1answer
749 views

Using an Arduino and multiplexer for writing to multiple outputs

I'm attempting to use the multiplexer setup in this article with my Arduino Uno to control the output of LED's, as a way to fully understand the principles of multiplexing. I'm working to modify the ...
0
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3answers
66 views

Turning an LED on when an error occurs, then turn it off after 2 seconds

I am currently working on making some test equipment for µUSB cables. The code is supposed to recoqnise when an error in the cable occurs. Most of it works as expected, but I have some trouble ...
3
votes
4answers
3k views

Hex to binary, LED blinking

I need to write a program that takes a user inputted HEX value and converts it to binary, then an LED blinks according to the number of 1's in the binary. For instance, if the value is 0xABC then ...
0
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2answers
165 views

Problem connecting 10W led + Led driver Directly Arduino Uno [closed]

can anyone give me an advice on connecting an 10W led + 12 volt drive to an Arduino Uno? it works without the board but when i tried to connect to Uno it doesn't work anymore. Thankyou