Why cant I initialize SD card in my mega

Ok this code was able to test for Arduino Uno with my SD card in my 3.5" TFT LCD SCREEN, but I don't know why it is unable to use it for Arduino Mega 2560.

/*
SD card test

This example shows how use the utility libraries on which the'
SD library is based in order to get info about your SD card.
Very useful for testing a card when you're not sure whether its working or not.

The circuit:
SD card attached to SPI bus as follows:
** MOSI - pin 11 on Arduino Uno/Duemilanove/Diecimila
** MISO - pin 12 on Arduino Uno/Duemilanove/Diecimila
** CLK - pin 13 on Arduino Uno/Duemilanove/Diecimila
** CS - depends on your SD card shield or module.
Pin 4 used here for consistency with other Arduino examples

created 28 Mar 2011
by Limor Fried
modified 9 Apr 2012
by Tom Igoe
*/
// include the SD library:
#include <SPI.h>
#include <SD.h>

// set up variables using the SD utility library functions:
Sd2Card card;
SdVolume volume;
SdFile root;

// change this to match your SD shield or module;
// Arduino Ethernet shield: pin 4
// Adafruit SD shields and modules: pin 10
// Sparkfun SD shield: pin 8
// MKRZero SD: SDCARD_SS_PIN
const int chipSelect = 10;

void setup() {
// Open serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}

Serial.print("\nInitializing SD card...");

// we'll use the initialization code from the utility libraries
// since we're just testing if the card is working!
if (!card.init(SPI_HALF_SPEED, chipSelect)) {
Serial.println("initialization failed. Things to check:");
Serial.println("* is a card inserted?");
Serial.println("* is your wiring correct?");
Serial.println("* did you change the chipSelect pin to match your shield or module?");
while (1);
} else {
Serial.println("Wiring is correct and a card is present.");
}

// print the type of card
Serial.println();
Serial.print("Card type: ");
switch (card.type()) {
case SD_CARD_TYPE_SD1:
Serial.println("SD1");
break;
case SD_CARD_TYPE_SD2:
Serial.println("SD2");
break;
case SD_CARD_TYPE_SDHC:
Serial.println("SDHC");
break;
default:
Serial.println("Unknown");
}

// Now we will try to open the 'volume'/'partition' - it should be FAT16 or FAT32
if (!volume.init(card)) {
Serial.println("Could not find FAT16/FAT32 partition.\nMake sure you've formatted the card");
while (1);
}

Serial.print("Clusters: ");
Serial.println(volume.clusterCount());
Serial.print("Blocks x Cluster: ");
Serial.println(volume.blocksPerCluster());

Serial.print("Total Blocks: ");
Serial.println(volume.blocksPerCluster() * volume.clusterCount());
Serial.println();

// print the type and size of the first FAT-type volume
uint32_t volumesize;
Serial.print("Volume type is: FAT");
Serial.println(volume.fatType(), DEC);

volumesize = volume.blocksPerCluster(); // clusters are collections of blocks
volumesize *= volume.clusterCount(); // we'll have a lot of clusters
volumesize /= 2; // SD card blocks are always 512 bytes (2 blocks are 1KB)
Serial.print("Volume size (Kb): ");
Serial.println(volumesize);
Serial.print("Volume size (Mb): ");
volumesize /= 1024;
Serial.println(volumesize);
Serial.print("Volume size (Gb): ");
Serial.println((float)volumesize / 1024.0);

Serial.println("\nFiles found on the card (name, date and size in bytes): ");
root.openRoot(volume);

// list all files in the card with date and size
root.ls(LS_R | LS_DATE | LS_SIZE);
}

void loop(void) {
}

So I don't know the problem, i tried changing the chipselect=10; to chipselect=53; but it still dont work.

How do you have the SD card wired? The SPI bus on a Mega is not on pins 11/12/13.

The Mega SPI pins are MOSI = 51
MiSO = 50
SCK = 52

On many SD modules the MISO line is run through a level shifter. The problem is that the SD library does not release the line properly. Somewhere in these pages may be a solution.

I ended up making my own module from the Adafruit mini SD module schematic.

The sd card is inserted into the LCD, then the lcd is plugged into the mega.

I suggest to carefully follow the instructions that came with the LCD/SD shield.

You will need to run software SPI to use the SD card on a Mega, unless you want to do some hardware modification.

The SDfat library has a SoftwareSpi example sketch.

Do i need to connect the lcd to pin 53? cause the SS pin is at pin 53 for Arduino mega?

You can use any available pin for the sd card select, pin 10 should work fine.

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