Serial.find or Stream.find

Hello i have the following code witch is working well :sweat_smile:
<if (mySerial.find(0x01))>
So i test if in the buffer there is the number 01 Hexadecimal, but i would like to test 3 numbers hexadecimal as
<if (mySerial.find(0x01, 0x04 , 0x04))>....
How can this be done and is it possible ?
And what is the difference between Stream ?

The Stream class is a common class that used by a few other classes to give them a few extra functions. For example the HardwareSerial class can also use the extra functions of the Stream class.

It is done this way: class HardwareSerial : public Stream

The Serial object for a serial port is a real object in code. The Stream class is not.

The functions of the Stream class are in Stream.h.

Do you want to find either one of those bytes, or a sequence of the three bytes ?
You can search for the sequence with: mySerial.find( "\x01\x04\x04")

Hi Thanks yes i want to look for a sequence of three bytes.
Can you explain a litlle the syntax why this is \x01 and not 0x01 ?
Can you tell me how to understand difference between object and class ? I think to understand this more i should go deeper in C+ language isn't it ?

A class is a description of how it should look, the blueprint.
A object is the actual "variable" that has a memory location. It is not just a "variable" because there are also functions in it.

See for example the example sketch "sweep":

#include <Servo.h>

Servo myServo;

The "Servo.h" has the definition for the class here. It is accompanied by "Servo.cpp".

The line "Servo myServo" creates the object "myServo" of the class "Servo".
:point_right: It is the same as "int data", which creates the variable "data" of the type "int".

In the C++ language, a variable value can be a decimal, a hexadecimal, a binary, a character and maybe some more:

byte data = 1;     // decimal integer
byte data = 0x01;  // hexadecimal value
byte data = 0b00000001;  // 8-bit binary value
byte data = 'A';   // Ascii value of 'A', which is 0x41

When a string is used, the so called "escape character" is a backslash.

char myText[] = "Hello World";            // Hello World
char myText[] = "Hello \x41 World";       // Hello A World
char myText[] = "Hello \x41 \"World\"";   // Hello A "World"

There are explained here: Escape sequences -

Let's have some fun.
You know an array of 32 integers is this: int myData[32];
For a class it is exactly the same: Servo myServo[32];
Let's put those 32 objects in action: (in the middle-upper of the screen is the start button).

Great thanks it's working well, and thanks for your explaination :slight_smile:

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