Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [arduino-uno]

249 questions
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Trying to replicate the behavior of an smartcard without sucess. What I am doing wrong?

Background: I am a software engineer and I am starting to research security hardware in my free time. The one I am starting with are contact smartcards, which are defined by the ISO 7816 standard. I managed to create a hardware to probe into the…
Filipe Rodrigues
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Arduino UNO voltage drop

My Arduino UNO board is powered with external 5V SMPS through the DC input. On measuring the 5V pin on the Arduino board pinout, I find the voltage to be around 3.7V and the L13 onboard LED glows quite dimly. If I connect an additional USB cable…
seccpur
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Burnt uno A0 pin!

I was making a voltage tester with the Uno and the input was A0. When I went above 10 volts into A0, that pin stopped working. Is it possible to fix the pin? If so, what do I do?
Logan S. Colon
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Opamp as a comparator for ac

Newbie here. please be easy on me. I have a spotwelder project where i need to sense when the secondary is shorted. The working of the pcb is as follows, my circuit detects the zero cross on the AC sine wave and triggers two Thyristors in a…
George
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Connecting two FSRs in Series

Does anyone know if i can connect 2 FSR in series and then in parallel to a fixed resistor, creating a potential divider circuit. Given the inaccuracies and low repeatability of force reading from one FSR, would connecting 2 FSRs in the above…
SSW
1
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1 answer

RPM Gauge Arduino.... Need the explanation of the Zener diode, what is the fuction on this circuit

Hello everybody... I need the electronic explanation of Zener diode.... I researched the Zener Diode I understand how it work .... But still don't understand the relationship with the zener with tip120, what is the function of the zener diode in…
Mangostain
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Is my Uno damaged?

The setup: Just the Uno and LCD connected so: LiquidCrystal lcd(7, 8, 9, 10, 11, 12, 13); Simple sketch to send and receive characters by monitor. Powered By Laptop USB LCD Back Light 8.5 mA. @ 5.04 v. Experiencing some flicker on LCD and Pin 13…
L. Martin
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Arduino + ULN2003 + stepper motors?

I have a need to control 2 stepper motors independently and a set of three 4" fans with variable DC voltage from 0-12vdc (not pwm). I read an article about using the Arduino Uno and a ULN2003 chip to control a stepper motor and I wonder if the…
Greg_M
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How does an Arduino actually read a high signal on a pin?

I have made circuit where you can see that it is reading some signal from a button. I've found in Arduino tutorials that there should be a pull-down resistor, which I don't really understand well. I've read tons of articles on the subject of…
Andrey Radkevich
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Arduino UNO analog input pins

I'm a student working with the Arduino UNO There's this question always bugging me for the analog input pins, how many samples does it take per cycle. I know it has 10 bit resolution meaning 0-5v would be 0-1023.I think since Arduino UNO uses ATMEGA…
Bolu
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Combining multiple bar type load cells to measure large weights

This is my first post here. I want to make a scale that can measure weights up to 60kg. I have three 20kg bar type load cells. I can successfully measure weights with the load cells individually (just up to 20kg of course). Is there a way I can…
Abdulrahman Solanke
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2 answers

Use a switch to override Arduino program

I am building a system where I am controlling 2 LED strips using an Arduino Uno, time chip and relay. I have managed to get the lights to turn on and off on 2 separate days at different times. Now I want to add a switch to override the program,…
Ephraim Cohen
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