Stack Overflow
Stack Overflow

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.

798 questions
-2
votes
2 answers

C# led panel controlling over ethernet with native dll

Hy, I had bought a "Huidu HD-E40" led panel a few days ago and the company sent me a .dll file. (I mean, it wasnt written in .Net). My question was the following: How can I use the file contents in C#. I had registered the dll via regsvr32, then…
tiborjan
  • 31
  • 1
  • 6
-2
votes
1 answer

How to keep screen from turning off when my flaslight app running?

Currently i am working on my first android project. When screen off led light also off any help guys.
Usman Jamil
  • 3
  • 3
-3
votes
1 answer

please help me answer this for me? my final exam

enter image description here Question 1- In a system like the one below, the user is expected to enter a 4-digit password. The first time the program runs, it should say "Enter Password". When the user presses the Square key after entering the…
Nasr Salm
  • 1
-3
votes
1 answer

FastLED, how can i change the Number of LEDs (NUM_LEDS) at runtime?

is it possible to change the number of leds at runtime (Arduino/FastLED) ? How can i do that? A small sample code would be nice because i am a newbie :) Thank you!
PascalL
  • 155
  • 3
  • 12
-3
votes
1 answer

PIC Assembly programming - LEDs with potentiometer

I'm completely new to Assembly programming, but unfortunately I must solve a task in a short time using Assembly and PIC16F887. My task is to move a flashing light on a row of 4 LEDs with a potentiometer. The frequency of the flashing light should…
Wolf
  • 1
  • 3
-3
votes
1 answer

Arduino, button delay LED output

So I am trying to have an LED react to a button. The problem I seem to be having is how to add a delay in between the button click and the led reacting. Essentially I want to, for example, click the button 3 times and then 2 seconds later have the…
BeamerEA
  • 103
  • 1
  • 7
-3
votes
1 answer

Led Strip via USB?

Is there a way to attach a LED strip to a usb cable, so i can power it with my pc? The LED strip got the following connections: red blue green power(about 5V)
SmokedMeat
  • 48
  • 5
-3
votes
1 answer

Arduino RGB LED random PWM Level

I am attempting to create a program that will randomly choose a PWM value for a RGB LED from a given Array. It works fine with the first color, blue. Bu then I nest in a second color, green, I loose the blue from displaying and only the green…
Nicholas Rice
  • 13
  • 4
-3
votes
1 answer

Camera flash not working

My application turn on/off flash on a lot of devices. But it's not working on LG-F500S Android verion 6.0 (Samsung S7 android 6.0 work fine). Who help me to find reason and solution, please?
Tran Hien Le
  • 1
  • 1
-3
votes
1 answer

How to control Brightness of a LED using c in RL78 Micro Controller?

As i am using a RL78 micro controller , i need a C code for controlling the brightness of a led.i have searched in the internet ,but of no use.... only some datasheets are provided.There is no exact calculation of duty cycle for PWM also,if anyone…
user3749242
  • 1
-4
votes
2 answers

Trying to press a button and toggle an LED flash at 2Hz until i press the button again

i'm trying to learn coding and this has really stumped me so i thought i would ask you lovely people. basically i'm trying to press a button and have an LED toggle on that is flashing on and off twice in a second, this will be continuous until i…
Ross Todd
  • 1
  • 1
-4
votes
1 answer

Understanding the logic behind the code for controlling an 8x8 dot matrix with a joystick

I found this code online for controlling a max7219 8x8 matrix with an Arduino, and I am struggling to understand a few things about the code. Here is the whole code: #include int UD = 0; int LR = 0; //Setting up…
Crispy Bagpipes
  • 7
  • 1
  • 6
-4
votes
1 answer

LED wont turn on using localtime [ARDUINO]

#include #include time_t now; struct tm *now_tm; int h,m,s; void setup(){ pinMode(D6,OUTPUT); } void loop () { now = time(NULL); now_tm = localtime(&now); h = now_tm->tm_hour; m = now_tm->tm_min; s…
Joseph St.
  • 1
  • 1
-4
votes
1 answer

How to check if a led is blinking during a period of time?

I need to check if a LED is blinking every 2 seconds...is it possible? I am using Arduino Mega 2560. Thank you.
Claude Hitech
  • 13
  • 5
-4
votes
1 answer

using processing for 3D image mapping

actually, I've tried to run the spherical POV. For run POV, each image should be converted to the number of lines which is used in each revolution, I've tried to use processing software to convert the 2d to 3d image by its library, but when insert…
Hamid s k
  • 138
  • 2
  • 6
1 2 3
…
53
54