Explain code lines

hey guys.

can you please help me i need explain for some code lines

#include "SD.h"
#define SD_ChipSelectPin 10
#include "TMRpcm.h"
#include "SPI.h"

TMRpcm tmrpcm;
tmrpcm.speakerPin = 9;
if (!SD.begin(SD_ChipSelectPin))

thanks in advance

That code includes the SD card library and defines pin 10 as the chip select pin for the SD card Then it includes the TMRpcm library (which plays sounds) and the SPI library which facilitates SPI communication with the SD card.

Then it creates a TMRpcm object called tmrpcm --- think of that as conceptually similar to creating an int variable with int myIntVariable --- also note that the name of the object could be anything you want, it does not have to be tmrpcm --- and note that C/C++ code is case sensitive so that tmrpcm is entirely different from TMRpcm

Edit to add ... Then it allocates pin 9 as the speaker pin

Finally if checks if it can begin communication with the SD card.

...R

#include "SD.h"    //include the SD library (expecting the files to be in the sketch directory)
#define SD_ChipSelectPin 10  //define the select pin (presumably for the SD reader)
#include "TMRpcm.h"  //include the TMRpcm library (expecting the files to be in the sketch directory)
#include "SPI.h"    //include the SPI library (expecting the files to be in the sketch directory)

TMRpcm tmrpcm;  //declare a TMRpcm object named tmrpcm
tmrpcm.speakerPin = 9;    //set the speaker pin for the tmrpcm object
if (!SD.begin(SD_ChipSelectPin))  //wait for the card reader to respond using the previously defined select pin

Looking at @UKHeliBob’s Reply #2 I see that I overlooked the use of quote marks in #include “SD.h” etc

It would be more normal to use #include <SD.h> which would cause the compiler to look for the library files in the libraries folder.

As mentioned in Reply #2, when quote marks are used the compiler expects the library files to be in the same folder as your .ino file.

…R