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What is an ICSP pin?

What is an ICSP pin? I have read that it is an AVR and a tiny programming header for the Arduino, but what is an AVR and what does an ICSP pin do?
SpaceMonk
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Does the Node MCU v3 (LoLin) not have a builtin led?

Trying a simple led blinking program I could not get the builtin led on a LoLin Node MCU v3 working. The LED_BUILTIN constant is set to pin 16 / GPIO16 / D0. Reading several articles and QA I think that the Node MCU boards are supposed to have a the…
Jan H
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Arduino powering from 9V battery

Yesterday afternoon I have left my Arduino running on a fresh Alkaline 9V battery (+ connected to Vin, - connected to GND). Today morning (16 hours later) the LCD display was no longer visible, and when I measured the volatage, I saw the battery was…
Suma
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Why does an `.ino` file have to be in a folder of the same name?

I'm trying to organise a very complicated project and I want to put all the actual code in a folder named src (source), but I want to keep the main .ino file as main.ino (it will also be in src). Then when I try to open the code, the IDE says that…
Dat Ha
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The use of 4.7kOhm resistor with DS18B20 temperature sensor

I was using a temperature sensor DS18B20 with Arduino. I've read that you should connect the digital input line and the 5V line with a 4.7kOhm resistor - like in the picture. Can someone explain why do we need to do this? And why this resistance?…
kamilazdybal
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6 answers

Arduino: How to get the board type in code

I want to write a sketch that can be compiled on different Arduino boards. I want to display on the PC which board is currently connected. This means that the user connects the PC via USB cable to the Arduino/Teensy board in which runs my sketch and…
Elmue
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2 answers

Button state changing randomly

I have a push button wired to my Arduino but it seems to be triggering randomly. I have one pin of the button connected to pin 2 on the arduino and the other connected to ground. void setup() { Serial.begin(9600); pinMode(2, INPUT); } void…
sachleen
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4 answers

Program an ATMega328P and use it without Arduino board

I'd like to use an ATMega328P for my project, I hope to do it without the Arduino board. I know with the Arduino IDE and an Arduino board I can program the microcontroller. However, would it be possible once I've programmed and debugged the…
George
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2 answers

Yún boot from SD card

I have an Arduino Yún, and it only has 16mb flash onboard for the Linux. I was wondering of it is possible to put a bootloader on the flash that uses the sd card as a rootfs? i want to be able to do more projects on it than those that can fit in 16…
TheDoctor
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What's the difference/relationship between Arduino and AVR?

I'd always thought Arduino was a microcontroller platform but the actual microcontroller is an AVR chip made by Atmel, or something like that made by someone else, based on a RISC ISA, and Arduino is usually used to refer to the whole circuit board…
user3383182
15
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3 answers

Why is the regulator very hot?

We have an LED strip connected to output 6 and is powered by the Uno board itself. Shouldn't be drawing too much current, only have 10 elements on the LED strip. While this LED strip is connected to the Uno, I noticed that the regulator is getting…
Chris O
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My code seems to be a train wreck

I am new to programming and I thought a simple project to do would be to create an ammo counter. I have been troubleshooting this code for several hours now, and can not figure out why my code is riddled with errors. Below is my program. Please give…
pvGuy
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Powering Arduino with Solar Panels

Clearly, an Arduino can be powered with solar panels. What is the most optimal configuration? Can you recharge and discharge at the same time? Is LiPO the best battery cache technology, or is there something more durable out there, for fielded…
0xF2
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What are the fundemental differences of different Bluetooth modules for beginners?

I'm a beginner to microcontrollers and electronics, albeit not really to computers and programming. Starting out with the Arduino, I came to a point whereby I'm really interested in getting my prototype to talk to a mobile device or a computer to…
Phil
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6 answers

How do I erase the memory of the Arduino Uno?

I'm just a tinkerer learning Arduino with my son and I was surprised that when I plugged the USB cord back in to the Arduino the program was still running and I thought to myself, "it's a good thing I didn't just blow anything up." So, what's the…
Peter Turner
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