Questions tagged [arduino]
Be sure to use the Arduino Stack Exchange for questions that are more Arduino and less electronics.
9,008
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How much current can I draw from the Arduino's pins?
What's the maximum amount of current which I can draw from each of the Arduino's pins without tripping any of the internal fuses? Is there a limit per pin as well as an overall limit for the whole ...
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votes
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What is the voltage range of a standard headphone jack from a phone?
I want to connect the output from the audio jack of an iPhone to an Arduino.
What voltage range can I expect to see on the audio lines from the iPhone? I assume that turning the volume up on the ...
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8
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How do I go from an Arduino on a breadboard to creating a real device?
My first Arduino project: I have made a headlight sensor that will activate an outside light when a car's headlights hit it. I know I could go buy one, but where is the fun in that?
Now I would like ...
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58
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How can I get my atmega328 to run for a year on batteries?
Scenario
I have created a nice electronic door lock for my dorm room. It is currently an Arduino Diecimila with a servo [un]locking the door. It has a numerical keypad with 3x4 buttons and 5 LED's (2 ...
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6
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Do I really need resistors when controlling LEDs with Arduino?
I'm just trying out Arduino Uno for the first time with 2 blinking LEDs on a breadboard. All the tutorials on the Internet seem to use a resistor. I do know the function of resistors, but does it ...
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Complete alternatives to the Arduino IDE? [closed]
I'm not that big of a fan of the official Arduino IDE (in terms of visuals), so I've started looking for nicer alternatives. However, most of the projects I've found are in alpha/beta and are ...
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Why is AVR used in Arduino?
Why is Arduino using AVR? I understand that they are the official processor but there isn't a reason the code couldn't be ported to an ARM or a Freescale architecture other than cost, right? As long ...
46
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How can I use a 12 V input on a digital Arduino pin?
I am creating a controller for a 12 V system using an Arduino Uno microcrontroller. For the outputs I am using a relay shield to switch the 12 V components. I have a 12 V toggle switch that turns on ...
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44
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6
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How to connect multiple i2c-interface devices into a single pin A4 (SDA) and A5 (SCL) on Arduino?
I want to add a real time clock module into my little project. I want to display both time and date on my existing i2c 2x16 LCD module.
Both i2c-interface real time clock module and 2x16 LCD module ...
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43
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Purpose of the diode and capacitor in this motor circuit
I'm hooking up a small DC motor to an arduino using an NPN transistor using the following diagrams I found online:
The circuit works, and I'm successfully able to make the motor run. Now, I'm ...
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Why does my circuit work on a breadboard, but not on a perfboard? I am new to soldering
I'm a total beginner when it comes to soldering, and recently I've been trying (and failing) to solder together a simple circuit I put together for a Raspberry Pi sensor.
Although it works fine on ...
41
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4
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What is "Arduino Optocoupler Disease"?
Another post on this site, when critiquing a pcb design, referred to "Arduino optocoupler disease" spreading across the internet. What type of design mistake does this refer to?
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Saving Arduino sensor data to a text file
How can I save data retrieved from a sensor to a text file on the computer?
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What's the difference between INPUT and INPUT_PULLUP?
On newer Arduinos, one can set pinMode to one of three states: OUTPUT,INPUT, and INPUT_PULLUP...
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Why do some pins have `~` signs next to their numbers?
I was looking at my Arduino Uno and I noticed that symbol by digital pins 11, 10, 9, ...
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Why should you use two resistors in parallel on an LED?
So I was looking over the Arduino R3 schematics and noticed this little design choice:
What is the reason for doing something like this? I mean it's hard to know what the designers were thinking, but ...
- 1,054
39
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Can I use the analog pins on the Arduino for my project as digital?
I am new to using Arduino, and I have an Arduino Uno. For the projects I've done, I've only used the digital pins.
I am building a small vehicle that uses stepper motors. I have run out of pins to ...
- 1,103
39
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1
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Why does my AVR reset when I call wdt_disable() to try to turn the watchdog timer off?
I am having a problem where executing a disable watchdog sequence on an AVR ATtiny84A is actually resetting the chip even though the timer should have plenty of time left on it. This happens ...
- 10.2k
38
votes
2
answers
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Selecting a MOSFET for driving load from logic
I'm looking to drive a magnetic door lock from an Arduino. I've found a question about driving a solenoid from an Arduino, which includes a circuit that looks perfect for this kind of situtation:
...
- 10.9k
38
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I2C 3.3 to 5.0 V conversion
I'm trying to interface a 3.3V I2C device to a 5V Arduino.
I don't have any problem with SCL line.
I can use a simple voltage divider but I have an issue with the SDA line as this is bi-directional. ...
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Is an Arduino Uno capable of running 24/7?
I'm curious as to the reliability and durability of the Arduino Uno.
Does anybody have experience in "killing" one due to excessive use?
If so, how long did it take for the board to fail?
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Why do Arduinos ship w/ 16MHz crystal instead of 20MHz?
Why do Arduino boards ship w/ 16MHz crystal instead of 20MHz? They are spec'ed for operating at 20MHz, after all.
I guess there are a few advantages to running more slowly (lower power consumption, ...
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Reliability of the Arduino platform for industrial use
I'm no electrical engineer (just mechanical) but I would like to apply some of my hobbyist experience to my job and implement various automated systems in an industrial (manufacturing) environment.
...
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33
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Embedded Programming for Beginners: Arduino or Raspberry Pi? [closed]
I'm a computer science student and I'm eager to expand my knowledge on embedded programming and electrical engineering.
I've read here that using tools like the Arduino microcontroller is a good way ...
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3
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Arduino pin spacing
How do you get around the annoying pin spacing on the Arduino?
Where pin 7 and pin 8 are not standard spacing.
Why is it set up like this?
- 5,070
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7
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Arduino Uno R3: Directly supply regulated 5V to 5V pin?
I'd like to use an Arduino Uno R3 battery powered a datalogger. I want do supply it directly with a Step-Up regulated 5V rechargable battery powersource at power ...
- 1,276
33
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1
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Active vs Passive Buzzer
I recently borrowed an Arduino Inland Basic Starter Kit. It includes an active and passive buzzer. What is the difference? I can hear a difference in sound when I use the ...
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How to drive brushless motor with Arduino?
Is it possible to drive a brushless motor directly with Arduino? Or should I revert on controlling a brushless motor ESC with PWM pulses?
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Can I develop with the Arduino using an IDE with more features?
The simplicity of the open source Arduino IDE is great, but a bit limiting sometimes - I like to use Netbeans for instance for other work that I do. Do any plugins exist for more fully featured IDEs ...
- 1,937
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Is there anything I should watch out for with cheap "Arduino" copies?
There's a plethora of cheap Arduino copies on eBay and similar sites, usually originating from the far east, that can be had for a significant chunk less than the official boards, especially if you're ...
- 1,937
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15
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Controlling 500 LEDs with PWM
I'm considering taking on a project that would involve individually addressing 500 LEDs, optimally with PWM support for each.
I'm planning on using an Arduino since I already have one, but I'm open ...
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Powering Arduino Nano 12volts
I know that the Arduino Nano can handle 12 volts, and it says it is recommended to power it between 7 and 12 volts. So I am wondering do I just hack together a 12 volt adapter to a Mini-B or is it ...
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Can Arduino be used in commercial products?
Is it legal for me to sell a product that's built with an Arduino? I know that it's open source, but does that mean I can sell my product for profit, or only for use in prototyping?
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How do I extend the number of analog (input) pins available to me?
I already know how to extend the number of digital pins on an Arduino using a multiplexer.
I want to increase the number of analog input channels that I have. One solution is to add another Arduino ...
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votes
4
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Is it advisable to stay stick to Arduino IDE?
Is it better to move to AVR studio (or any other better alternative?) over the Arduino IDE. Feel like it's so simple and childish. I need to know the experts idea and choice..
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Is there any way to simulate a program run before burning it onto the board?
Programs may, at times, have runtime errors. These are sometimes hard to find and can easily be missed. Is there any way to test the program before actually burning it onto the board ?
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Measure Lithium ion battery voltage (thus remaining capacity)
What I am working with: I am running my self-made Arduino board (in the sense that I use the Arduino bootloader and code editor) at 3.3V, and powered from a Lithium ion battery, which is USB-charged ...
- 4,952
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3
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JTAG debugging AVR
Can anyone advise what hardware and software is required for debugging AVR in circuits?
- 4,819
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10
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Is there a way to stop servos from "shaking"?
Very simply, I am controlling servos (9g micro servos) based on some data read in from elsewhere. Everything works fine except that the servos will constantly "shake." That is, they vibrate ...
- 3,461
22
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3
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Why am I cooking MOSFETs?
I've made a very simple MOSFET LED driver that uses the PWM of an Arduino Nano to switch a MOSFET which controls the power for about 16 meters of LED strip.
I am using STP16NF06 MOSFETs.
I am ...
22
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3
answers
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How do I create a permanent application from something prototyped with Arduino?
Part one of a three part series on transitioning from Arduino to a plain AVR microcontroller and minimum supporting components (part two, part three)
I've built up a project on my Arduino Uno to ...
Pete
22
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How to properly use a relay module with JD-VCC from Arduino/Raspberry?
[EDIT]
A quick benefit of JD-VCC, is that allows you to control the relays that are 5V with 3.3V GPIOs. Check the full answer to understand why :)
[Original question]
I got two 4-relay-modules and I ...
- 1,256
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Why do we need hardware programmers?
I use a Boarduino and a 30-row bread board to program my ATtiny. I load a not too complicated sketch called ArduinoISP (included by default now in the Arduino IDE), and suddenly I have a working ...
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How can 8-bit processor support more than 256 bytes of RAM?
If a 32-bit processor can handle approximately 4 GiB of RAM (i.e. \$2^{32} = 4 294 967 296\$) bytes, why does my Arduino Mega 2560 have 8 KiB of SRAM, if being a 8-bit processor allows it to handle ...
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9
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Is Arduino ideal for making a HRNG (hardware random number generator)?
I'm putting together a design for a hardware random number generator that will utilize multiple sources of entropy (combined):
Ambient light
Ambient sound (and sound levels)
Ambient temp
Ambient ...
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21
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9
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How to graduate from Arduino to using a microcontroller directly?
I've been working on an Arduino project. After I get everything working using the Arduino, I would like to move to a solution that does NOT use Arduino. That is, I would like to use a microcontroller ...
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How can I detect which arduino board (or which controller) in software?
I have a project that I want to work on either a Uno or a Mega (or even a Due) and it would be nice if I didn't need two versions of the software. For example, on a Mega, to use SoftwareSerial, you ...
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How to water-protect my Arduino?
I am building a watering system with an Arduino. Basically it runs on a track with a hose that drips water down on plants a couple of times every day. Its outside, and water might sometimes get from ...
- 1,103
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8
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How many individual lights can an arduino control
I want to use a regular Arduino board to control LEDs - what is the most lights I can control individually from the board?
Is there a tutorial on how to hook it up?
- 5,070
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Is it possible to use multi gigabyte DRAM modules with a microcontroller?
I have two leftover 2GB RAM modules that I removed from my MacBook Pro when doing an upgrade. I was just wondering if these were usable with, for example, an Arduino. I'd be too much of a beginner to ...
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