1,627 questions
184
votes
21
answers
663k
views
"avrdude: stk500_getsync(): not in sync: resp=0x00," aka Some Dude Named Avr Won't Let Me Upload My Program
I made an awesome program the other day, and I wanted to upload it to my Arduino. After clicking the upload button, some mean dude named avr came along and stopped me, saying:
avrdude: ...
105
votes
3
answers
116k
views
Have I bricked my Arduino Uno? Problems with uploading to board
I can't upload sketches to my Arduino Uno.
Have I "bricked" it?
What steps can I take to work out what is wrong?
What can I do to fix it?
135
votes
4
answers
118k
views
How can I handle the millis() rollover?
I need to read a sensor every five minutes, but since my sketch also has
other tasks to do, I cannot just delay() between the readings. There
is the Blink without
delay tutorial
suggesting I code ...
21
votes
3
answers
9k
views
Classes and objects: how many and which file types do I actually need to use them?
I have no previous experience with C++ or C, but know how to program C# and am learning Arduino. I just want to organize my sketches and am quite comfortable with the Arduino language even with its ...
5
votes
1
answer
1k
views
How do you combine 2 different sketches together
(Before you down-vote this, note that it is a "ringer" to answer a FAQ, with a self-answer.)
This question comes up all the time. How do you combine 2 different sketches together? Say I have a sample ...
244
votes
13
answers
473k
views
Can I program for Arduino without having a real board?
I would like to start the development of some basic Arduino projects but I don't own an Arduino board yet. Is there a way I can write my code and emulate/test it using a desktop computer so after my ...
1
vote
3
answers
13k
views
My Arduino isn't showing up on my computer. What should I do?
You have your spangly new Arduino board, you've installed the software, and you plug it in. Nothing happens. Diagnosing problems may be a little tricky for the beginner, so what hoops should you go ...
15
votes
1
answer
5k
views
What happens when code is uploaded using the bootloader?
When I upload a new sketch to my Arduino Uno using the Optiboot bootloader, what really happens?
What is sent to the Arduino?
How does it respond?
What does "not in sync mean"?
What is "in sync" ...
67
votes
2
answers
229k
views
How do you use SPI on an Arduino?
With reference to the Arduino Uno, Mega2560, Leonardo and similar boards:
How does SPI work?
How fast is SPI?
How do I connect between a master and a slave?
How do I make an SPI slave?
Please note: ...
62
votes
7
answers
230k
views
Is there any way to download a sketch from an Arduino?
I made a sketch, but then I lost it. However, I uploaded it to the Arduino before losing it. Is there any way I can get it back?
18
votes
1
answer
28k
views
How do interrupts work on the Arduino Uno and similar boards?
Please explain how interrupts work on the Arduino Uno and related boards using the ATmega328P processor. Boards such as the:
Uno
Mini
Nano
Pro Mini
Lilypad
In particular please discuss:
What to use ...
94
votes
22
answers
19k
views
What are the other IDEs for Arduino?
The basic Arduino IDE lacks a lot of the sophistication present in other IDEs such as code completion, code collapsing, folder organisation, etc. Are there other IDEs that allow programming in C or C++...
65
votes
13
answers
84k
views
Is there a way to have more than 14 Output pins on arduino?
Is it possible to have more than 14 output pins on the Arduino, I am working on a project in which I need to light up several LEDs individually. I only have an Arduino Uno, and I don't want to get a ...
10
votes
1
answer
11k
views
Adding a custom board to the Arduino IDE
I would like to know what is the procedure for adding a custom board to the Arduino IDE?
My custom board is similar to the Arduino Zero. Instead of using the ATSAMD21G18, my board is based around the ...
2
votes
1
answer
462
views
Wanted to control 2 servos with serial read [closed]
I want to use 2nd servo only when 1st is in up state by asking user whether he wants to fire or not.(code in bold is not working )
#include <Servo.h>
Servo myservo;
Servo trigervo;
...