Questions tagged [class]
A custom structure in C++ (and various other languages) which can contain member data and functions. An instance of a class is called an object.
122 questions
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What overheads and other considerations are there when using a struct vs a class?
C on embedded systems has traditionally use structs to hold structured data.
Arduino brings C++ to the table, so we can use classes instead.
Lets say we have two different data structures which ...
- 5,430
21
votes
3
answers
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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 ...
- 503
7
votes
1
answer
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Arduino Servo won't move when using classes
I'm trying to make a class work with Arduino, however it doesn't seem to trigger properly. The code is compiling perfectly, and it's supposed to control the leg of an hexapod. Also, the example sweep ...
6
votes
2
answers
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"undefined reference to" - C++
Hi fellow programmers,
I started to program Arduino a little deeply and popped out the following error when I was writing a class to read the pulses of a Hall effect flow rate sensor:
SensorDeVazao....
- 167
4
votes
2
answers
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using enums in functions
Given the following enums
enum RelayState { RELAY_OFF = HIGH, RELAY_ON = LOW };
enum class CrossingZoneState: uint8_t {
CROSSINGZONE_CLEAR = 0, // no train in crossing area, also initialized ...
- 360
4
votes
2
answers
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incompatible types in assignment of 'int*' to 'int [0]'
I was coding a class for "a kind of gun". I have this code for the classes:
Gun.h:
#ifndef Gun_h
#define Gun_h
#include "Arduino.h"
class Gun
{
public:
Gun(String identifier, String name, int ...
- 197
3
votes
2
answers
3k
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Attach the Arduino ISR function to the class member
I intended to use a timer interrupt for limited instances of a class in my ESP32 Arduino project. My first code conception was as follows:
portEXIT_CRITICAL_ISR(&lock0);
}
...
- 143
3
votes
1
answer
57
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Class is not tracking changes to a private field
I have a program where a device registers itself with a command object. The command object is losing track of the registrations. The following program repeats "0 devices registered" even though when ...
- 233
2
votes
1
answer
8k
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pass class internal function as callback
I am trying to pass a class internal function as a callback function within the class. The error behavior is similar to this problem. Whatsoever, I was unable to construct working code based on that ...
- 143
2
votes
2
answers
2k
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Arduino Libraries: Declaring variables as public?
How come I never see any Arduino Library expose some of it's internal variables as public in the header file? I only see functions which are declared as public, while every variable is declared ...
- 123
2
votes
1
answer
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Use ISRs inside a library more elegantly
At the moment I try to make a library which uses attachInterrupt(?,?,RISING) to read a sensor. The article of Nick Gammon on Calling an ISR from a class helped me a lot, but his "Glue routines" get ...
- 31
2
votes
2
answers
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How do I correctly use enum within a class?
I am trying to set the status of an object from a private enum and I'm not sure how to get the private member to the public version in the constructor, and I'm pretty sure I should not be using byte ...
- 142
2
votes
1
answer
2k
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AttachInterrupt - fail to initiate inside a class [duplicate]
I'm trying to create a class that uses attachInterrupt, but get this error msg:
In member function 'void ledDoor::attach()':
ClosetLedStrip:31:82: error: invalid use of non-static member function
...
- 1,049
2
votes
1
answer
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Create a library without a class?
I'd like to know if it's possible to create a library for Arduino that does not contain a class, just functions.
I know how to create a library with a class, but I'd like to create a library of ...
- 35
2
votes
1
answer
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Mysterious behavior when using objects
I am writing a project that involves using complementary filters to combine gyroscope and accelerator readings in 3 directions. The relevant code is below.
class CompFilter {
public:
long ...
