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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.

6
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1answer
161 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, ...
1
vote
1answer
70 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 ...
2
votes
0answers
1k views

Arduino sketch works on ATmega1280, but doesn't work on ATmega328 (Arduino Nano)

I'm working on arduino based RGB LED strip controller. This simple schematic was used to control 12V channels via 5V PWM signal from arduino: I have also connected an HC-05 bluetooth module to be ...
1
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0answers
58 views

LED strip with 12v power connected to ESP32

I'm looking at controlling a ws2811 strip and I have seen mention that you should share the same ground between the strip and the controller, which does make sense. I do not currently have a proper ...
1
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0answers
188 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 ...
1
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0answers
22 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. ...
1
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0answers
59 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 ...
1
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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 ...
1
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0answers
471 views

Switch on/off LED 24V using a MOSFET

I try to switch on/off IKEA Ledberg LEDs which are powered with 24 V using the setup from this tutorial video: https://www.youtube.com/watch?v=sVyi7yWuXxs I use a IRLB8721PBF MOSFET. When I switch ...
1
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0answers
134 views

Sparkfun Spectrum Analyzer: Problems with frequency bands

I bought around 2 years ago the Spectrum Analyzer Shield from Sparkfun, but I never had the time to do something with it. Recently I found the time to start a project to build a graphical equalizer. ...
1
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0answers
162 views

LED Webserver control not working

I've got an Arduino Uno and Ethernet shield, trying to test it out with a simple on off switch for the on-board LED. My Code is this // FILENAME = LED2.ino // SOURCE= http://www.instructables.com/id/...
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0answers
661 views

troubleshooting - Turn on a single led in a ws2811 ledstrip with an arduino Uno with FastLed

I want to to turn on a single led in a ledstrip running on ws2811 with an Arduino Uno. The problem is that when I try to turn just one of them on, they all three light up. The strip is a 3-wire ...
1
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0answers
457 views

Testing for bad WS2812B?

I bought a 100 pack of WS2812S SMDs last year (product link) and wired most of them together for a string of Christmas lights for a tree. It was more work, but way cheaper (at the time) than buying a ...
1
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0answers
73 views

Determining if an LED on another device is on

I'd like to check if this circuit I'm making is correct -- I'm concerned I'll mess up my Arduino. Essentially, I would like to determine if an LED on another device is on or not by measuring the ...
1
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0answers
237 views

Help with Arduino Due and APA102 LED strip Vs Matrix

I am in a fix since last one week regarding this: As mentioned in a previous question (asked here only), I have been working to develop a APA102 LED based display. Now for this I have an Arduino Due. ...
1
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0answers
236 views

Parallel Chaining of APA102 LED matrices

I have four APA102 LED matrices (those flexible ones) and I want to connect them together to make a display for showing images. Now my problem is this: Consider the coordinate system with four ...
1
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0answers
198 views

Parsing UDP text from a Command using UDP

I want to send a parameter from my computer (i.e using Hercules software) using UDP protocol to my Arduino with Ethernet shield to turn 2 LED on and off (each of them). The command I'm using is: $A&...
1
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0answers
330 views

Bluetooth shield with ardudroid RGB LED

Here is their code: /* PROJECT: ArduDroid PROGRAMMER: Hazim Bitar (techbitar at gmail dot com) DATE: Oct 31, 2013 FILE: ardudroid.ino LICENSE: Public domain */ #define START_CMD_CHAR '*' #...
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0answers
1k views

Blinking LEDs as fast as possible at different rates.

I'm trying to use the Arduino Uno to make a strip of LEDs blink as fast as they can while still blinking at different rates. I am able to get them blinking at different rates but the blinking is very ...
1
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0answers
700 views

Arduino PWM LED blinking on four pins, each pin's intensity and time period based on the previous pin

I am trying to make four LEDs glow using my Arduino, based on some relationship between them in terms of brightness and the time for which LEDs glow. For example, the relationships are: pin_3_value =...
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0answers
209 views

Arduino based temperature sensing circuit

I've currently got a setup where I am using a 2 thermocouple setup using MAX31850 and the circuit looks exactly as mentioned here using the external power option. (https://learn.adafruit.com/adafruit-...
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0answers
433 views

Pro Mini 3.3v + Neopixel not working when disconnected from USB

I'm doing a project using an Arduino pro mini 3.3v and Adafruit's Neopixel. I've flashed an example (strand example) from the Adafruit Neopixel's library sketch into the Arduino using the FTDI Basic ...
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0answers
422 views

What bytes do I send to the MAX7221 to light an LED (in an led Matrix)?

Datasheets LED Matrix (p2): https://www.circuitspecialists.com/products/pdf/M105057CHR1.pdf MAX7221: https://www.sparkfun.com/datasheets/Components/General/COM-09622-MAX7219-MAX7221.pdf ...
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0answers
266 views

Connecting Indicator LEDs to Arduino Pro Mini

I'm new to electronics and unsure whether my design below will work as intended. XBee Series 2 and Arduino Pro Mini 5V are used. There are 4 LEDs, each with the following roles: LED1: Flicker when ...
1
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0answers
541 views

7 Key Educational Piano with Capacitive Sensor

I am working on a project for grade 10 computer science. I am supposed to make a piano that has 7 keys using a capacitive sensor, and the piano is supposed to teach you songs like Twinkle Twinkle ...
1
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0answers
1k views

Controlling multiple LED strips with arduino

I want to control several (undecided) cut strips of these led lights:here. I want to be able to turn the LEDs on and off from the arduino, but I know that the voltage is too high to work with with ...
1
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0answers
972 views

Controlling LED delays via keypad

I'm trying to turn on LEDs based on delays entered by keypad and the same for turning them off, but the LEDs are not responding. Here is the code I'm using: #include <Keypad.h> const byte ROWS ...
0
votes
0answers
29 views

What's the required voltage for ws2815?

I am working on ws2815 led strip with the esp8266 on arduino 1.6.6 fast led library.Using CD40109B level shifter to convert 3.3V of esp output to 12V .It's working fine upto 31 leds according to the ...
0
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0answers
39 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
votes
0answers
141 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
votes
0answers
70 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
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0answers
65 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 ...
0
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0answers
25 views

Why won't this “Simon Says” sketch accept button input?

I tried to create a "Simon Says" game with Arduino, 4 INPUT_PULLUP type buttons and 4 leds. The random sequence generating part apparently does the trick, but the same can't be said for the "input ...
0
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0answers
114 views

256 (8x32) LED Matrix via ESP32-Pico-Kit_V4 possible? (Daft Punk Helmet)

I am currently planning on a Daft Punk Helmet. But the available kits are terribly expensive. I am looking forward to using a 8x32 LED-Matrix(with 256 separate 5mm LEDs) and having a few different ...
0
votes
0answers
32 views

How to upload data to program over USB port

I am working on a set of Visual poi (like these https://lighttoys.cz/store/vpoi/v4/) and need to upload new pictures to the controllers every now and again. Currently I use a program to convert a ...
0
votes
0answers
164 views

Push button to LED Code does not Properly Execute

I was making a program that would randomly select an order of lights utilizing the random-seed and random functions in Arduino. After selecting an order randomly, the LEDs would proceed to go off ...
0
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0answers
35 views

What am I doing wrong? (LED PROBS)

I have chopped up and spliced together some USB cables to combine with several strips of LEDs to create (what should be) a daisy-chainable setup that I can use to make a light fixture. Below is a ...
0
votes
0answers
139 views

Can 2 or more LED strobe Lights Flash in Sync?

I'm trying to build a strobe light that has at least 1 mode that can sync with another unit. The strobe light has 2 colors, white and red which are driven by 2 qlite drivers which are controlled by ...
0
votes
0answers
67 views

Arduino Code hang

I am working on a project to dim/brighten the LED lights between each hour. To make the program readable i have only kept the code for few hours. For example if T1 is at 255 PWM and T2 is 20 PWM, the ...
0
votes
0answers
138 views

Fading 5 LED strips

I'm trying to fade 5 led strips (12 V with MOSFET), with push of a button. A user can push any or multiple buttons and leds fade in, when button is released, they slowly fade out. Now I almost got It ...
0
votes
0answers
111 views

Arduino: Output state of pin (~3) running PWM signal. Is it ON or OFF?

On my Arduino UNO, I have set pin ~3 to run PWM. Is there a way to know when the signal is ON and when it is OFF? I am trying to eliminate background noise from an LED light intensity reading by ...
0
votes
0answers
64 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.
0
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0answers
7k 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
votes
0answers
672 views

sunrise alarm clock using android to set alarm time

I'm trying to create a sunrise alarm clock, controllable via Bluetooth by my phone (running android marshmallow) with an Arduino nano, real time clock module, and Bluetooth module. these will then ...
0
votes
0answers
117 views

Help with LED 'ON' duration during PIR motion event in this sketch? (beginner)

I cobbled together a sketch, based on some others I found vie google search, to send motion events from a PIR sensor to a MQTT broker. It works really well, however, there is an issue with turning on ...
0
votes
0answers
95 views

Safe way to setup I/O to read switch AND manipulate LEDs at the same time

I would like make educational shield for playing with Arduino, where (at least couple of) pins would be connected to grounded switches (so could be configured as INPUT, or INPUT_PULLUP a digitalRead() ...
0
votes
0answers
449 views

NeoPixelClock pulsating effect

I want to make an anduino based neopixelclock pulsate while displaying time. Code: https://codeshare.io/5M8rJ2 Inspiration: http://www.tweaking4all.com/hardware/arduino/adruino-led-strip-effects/
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0answers
616 views

Problem with arduino nano and nrf24l01

I connected my clone of arduino nano (with CH340) and not-clone of arduino leonardo to nrf24l01 module and I have uploaded simple sketch which turn ON diode when I press button on another board. ...
0
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0answers
647 views

Using Arduino Uno to make digital LEDs go to music

I've just started playing around with Arduinos... I found relatively simple project on youtube: https://www.youtube.com/watch?v=5U354Qp6j24. I followed the instructions, loaded up the code, and ...
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votes
0answers
22 views

Using different data-outputs for SW2812 programmable LED

I am planning on building a DIY light chandelier (of sort). The build will be four circles of different sizes within eachother. The inner circle has a diameter of 30cm and the other 3 has another 30 ...