Most voted "arduino" questions
Arduino is an open-source electronic prototyping platform based on flexible and easy-to-use hardware and software. It is aimed at artists, designers, hobbyists, and anyone interested in creating interactive objects or environments. This tag should be used when the problem is specific to Arduino.
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32
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answer512
viewsArduino I2C sends unexpected NACK
I’m wearing a Development board of microchip (explorer 16) with the pic24f128ga010 as Master and the Arduino as Slave. The PIC is sending everything right, but for some reason NACK for all the date,…
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20
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answers4153
viewsWhy are local variables avoided in Arduino?
In several code examples for the Arduino I note that there is almost no use of variables in local scope. One of the examples present in the IDE: Analog > AnalogInput: int sensorPin = A0; int…
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17
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answer270
viewsError in serial port of Arduin with communication between C and Perl
I have to make a language communicate with the arduino and vice versa. I own the program at C and I have to modify it for this project, the language I have to use is Perl. Follow the code I have:…
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9
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answer6826
viewsHow to transform non-digital data into digital data
I would like to know how you would develop a software that displays the statistics of a car for example. Speed is not a digital data until I turn it into one. How to do it ? Is microcontroller,…
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9
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answers3219
viewsConnect Arduino to SQL Server
I’m looking to keep an updated database with the outputs of the Arduino sensors. I wonder if it is possible to connect directly the Arduino to SQL Server for sending and receiving data. Or the only…
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8
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answer5423
viewsHow do I program for Avrs in C/C++? And using Arduino?
I’d like to know: How to start microcontroller programming ATMEL AVR in C/C++? What software can I use to compile my program? What software can I use to upload my program? Where I find the official…
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8
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answer253
viewsHow can I record information with Arduino?
We are developing a reading system to check parameters of electrical pulses that are measured directly from the electrical network of a household, and for this to happen we need to read and archive…
arduinoasked 9 years ago Pena Pintada 4,678 -
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answers9249
viewsControlling extra inputs and outputs in Arduino Uno and Mega 2560 via software
During the development of an Arduino project, I needed more digital terminals (inputs and outputs) in addition to those indicated on the board. You can control, via software, more extra digital…
arduinoasked 10 years, 8 months ago carlosrafaelgn 4,769 -
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answers1244
viewsHow to employ multithreading with Rduino
I’m making a bell with Andy. This bell shall be composed of: 01 Arduino UNO, 01 Buzzer, 01 Transmitter 433 Mhz, 01 Receptor 433 Mhz. My doubt revolves around how I can treat the listener who will be…
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7
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answer1192
viewsArduino with Millis function - computer cycle
I’m trying to build a computer cycle with Arduino that displays displacement and speed on a 16x2 LCD display, but I’m having trouble calculating speed. The travel is working perfectly, but the speed…
arduinoasked 9 years, 9 months ago Anthoni Silva 71 -
6
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answer867
viewsInternet of Things and Remote Access
I have a prototype of home lamp automation using Arduino in case I want to control my sensors off the local network which the appropriate solution nowadays? There are some other options besides…
arduinoasked 8 years, 11 months ago Daniela Morais 4,687 -
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answer7213
viewsLibraries for communication between Arduino and Android
I am a beginner Arduino programmer trying to make a connection to my mobile phone (Android) and / or my laptop using Java. I’ve done some research and so far I’ve found three examples of how this…
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5
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answer1721
viewsArduino mandar GET to PHP page
I have the following code on the Arduin: #include <SPI.h> #include <Ethernet.h> #include "DHT.h" #define DHTPIN 2 #define DHTTYPE DHT11 DHT dht(DHTPIN, DHTTYPE); byte mac[] = { 0xDE,…
arduinoasked 8 years, 9 months ago Rodrigo Segatto 743 -
4
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answers329
viewsStore SMS message in variable
I’m having trouble saving a text message in a variable. The idea is to send an SMS with a command and later use a conditional operator to activate or deactivate a relay. But I can’t save the SMS…
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4
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answer2298
viewsHow to display variable char on the Arduino LCD?
I was trying to print a variable char on the Antarctic LCD but I can’t, always error when I try to compile the code. I’ve pulled up the LCD library and the line I’m trying to print is next:…
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4
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answer5292
viewsHow to make an HTTP GET request for a web service with Arduino
With a request via GET to a web service with Arduino, using the following URL and passing a parameter http://192.168. 0.1:8080/automation/Sensor? value=###, where ### is variable and is updated…
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4
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answer125
viewsWhat happens on these lines in C++?
This is an Encoder reading routine that detects which direction of Encoder rotation. The references are left and right pins appreciated as MSB and LSB bits. The Code works perfectly, but I do not…
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4
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answers107
viewsDifficulties in the Scilab
I am communicating via USB -> Arduino Serial and receiving values from a sensor. But sometimes values have different sizes and the function used to receive the serial bytes needs a defined amount…
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4
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answers767
viewsDifference between local variable VS global variable
In my micro controller classes the variables are always defined globally and very rarely locally and I would like to know why, because in my mind it makes a difference between being global or local.…
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4
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answer138
viewsTake two values from Arduino and display in C#
I have two Ultrasonics linked in my Alpha, and I’m using this code to read their values normally: #include <Ultrasonic.h> Ultrasonic ultrasonic(11, 12); Ultrasonic ultrasonic1(8,9); const int…
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3
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answer1286
viewsSocket connection causes an exception on Android
The code below works perfectly when only used with a Jbutton, but when passing to Android happens the exception (Exception). I have located that the error is in clientSocket = new Socket(serverIP,…
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3
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answers7507
viewsArduino and Android Bluetooth Connection (Java) - Inputstream storing old data
I’m making a class in Java very simple, just to simulate the communication of Android with Arduino via Bluetooth. The idea is the following: The Arduino every 5 seconds will light and erase an LED.…
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3
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answer966
viewsArduino UNO restarts when using serial port outside the IDE
My Arduino UNO is rebooting when I use its serial port with a Python script. But when I open the serial terminal from the Arduino IDE and run the same Python script, it works normally. Why this…
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3
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answer265
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3
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answers1237
viewsHow can I get more accurate values by dividing two long?
I’m programming a CNC on my own, and I’m in the middle of my code, and now I have two variables like long which, when divided results in an exact fractional value, but the Arduino returning a…
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3
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answers76
viewsEnter decimal values on the computer keyboard and get the answer on the computer screen using Arduino
I want to have the Arduino connected on my computer and through the computer keyboard enter two values with cecimais, for example 10.5 and 12.7 and the Arduino perform the sum and present the result…
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3
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answers116
viewsLeds and Arduino board
Good night, I am programming an Arduino uno using C. I am using an RGB led on three PWM outputs. However, now appears the need to turn on more leds, hundred leds at the same time, but in addition to…
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3
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answer2578
viewsTcomport - Delphi Xe7
I need a component that can read serial port, I’m making an application integrating with Arduino. I saw that there is Tcomport, but I can not install in Delphi xe7, someone has already managed??…
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3
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answers290
viewsHow to convert string array to string?
In a program for Arduino, I have an array of strings but it seems that the function where I will use this data only accepts string. How do I convert an array to a string ? File prog =…
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3
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answer1963
viewsSend Arduino data to Android (ultrasonic sensor)
I made this code to receive data from an ultrasonic sensor on a cell phone Android. After passing the application to the mobile and the code to the Arduino, it can only connect, but does not show…
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3
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answers471
viewsSending computer vectors to the Arduino
Hello, I’m with a project that uses the Arduino to perform some operations for me. However, these operations use vectors. I need to somehow send a computer vector (other than by Serial) to the…
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3
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answers2052
viewsHow to create a single button to power on and off bulb for Arduino in html?
Good afternoon guys!! I’m new to everything in the programming universe, but I’m venturing into Rduino, php and html!! I would like to know how to pass two values in a single html button. Type when…
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3
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answers542
viewsArduino + Module SIM900 + PHP + Mysql - POST method problem
Good afternoon to all!, I am developing a project that consists in the communication of a module SIM900 with an application, and doing the interaction of the two will be a server WEB + Database. The…
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3
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answer146
viewsHow to encrypt a C-drive?
First to locate them, I have an idea of security, and to be able to put this idea into practice I would need to learn how to encrypt a USB stick. The idea is that the USB stick works as a 'key', and…
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3
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answer533
viewsHow to store data from Arduino in a Java string?
I need to store data from Arduino in the Java via serial communication only the values sometimes not filled in completely. I am using the library rxtx. //trecho do código para leitura int available…
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3
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answer109
viewsWhat is the functionality of this line of code?
I’m trying to translate the following code to C++: https://github.com/JohanLink/Ball-Balancing-PID-System/blob/master/pythonCodes/interface.py I wanted to understand what the following line does:…
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3
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answer804
viewsReceive data from Alpha via serial in C#
I need to make an application that sends and receives data from an Aryan Eonard. I searched some examples of serial connection between c# and Arduin application and in all examples I had the same…
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3
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answer126
viewsLosing data while communicating with C#
Man Arduous sends data continuously to my C# via serial port. However, I understand that the first figures sent by Arduous are simply disappearing, sometimes disappear more numbers, sometimes less,…
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2
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answers105
viewsArduino - 8x8 matrix
I have an 8x8 led matrix and an Arduino uno and I intend to display some sentences in the matrix but I have not found in any way the datasheet. The numbering is HS-2388BS. There is another way to…
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2
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answer161
viewsDoubt pinout Atmega328
I’m using Atmega328 in my project, and I was looking at the datasheet and I’m doubting whether the pins 22, 23, and 24 of the atmega328 work as Analogue and Digital, I’m in doubt. Someone could help…
arduinoasked 9 years ago Desenvolvedor 185 -
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answer1048
viewsMultiples serial communication with Atmega328
I am using the atmega328 serial to control a bluetooth module, but I would like to use the same serial output to communicate with another atmega328, as I can do ?
arduinoasked 9 years ago Desenvolvedor 185 -
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answer2359
viewsMac , Andy does not recognize the door imusb
I bought a UNO Rduino ( I believe it’s not the original ) , I downloaded the IDE , installed normal , connected the board ( lit normally , I went to the IDE on tools > boards and selected…
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2
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answers56
viewsSoftwareserial library for Galileo
Good morning, I would like to know how to use the Softwareserial library in Galileo Gen 2, or alternatives to be able to use the Shield ICOMSAT 1.1 in Galileo. Thank you.
arduinoasked 8 years, 11 months ago Gustavo Caetano 21 -
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answer200
viewsIs there a specific library to work with android and Arduino?
I’m with some automation projects, and I wanted to develop my own app, which controls an Arduino. With little research, I realized that there are several tools that create this communication and…
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2
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answer124
viewsDoubt in working with multiple
I’m developing a Sketch and I need to use multiples of one, but I guess I’m not knowing how to work right with them. I have a loop FOR that goes from 1 to 72 and I need to count and go showing the…
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2
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answer66
viewsInformation Duplicating in SDCARD
Hello I’m studying the use of SDCARD on the Arduino and I need to record the values of the sensors in a file. TXT, but it keeps duplicating the information in the file . TXT as it goes through the…
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answers498
viewsARDUINO Writing data to SD card over Shield ethernet
Good night I am wanting to make the Arduino uno record data on an SD card I do not have the module for SD card for Arduino However I have the module ethernet Shield, which has an input for SD card…
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2
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answer45
viewsCapture Started Strings with %t and %u
What modification can I make to capture humidity and temperature of my serial port to insert within a variable the humidity that is printed on the serial port as %u00.00 and the temperature %T00.00.…
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answer135
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answers155
viewsWeb sockets how to make a connection by selecting an IP
I’m doing a project that involves connection to a ESP8266 through websockets, but as the ip of ESP no and static need to make manual connection with the IP. But in the code below when I put the…