#include <SD.h>
#include <SPI.h>
#include <Arduino.h>

#define SCK   36                //SCK on SPI3
#define MOSI  35                //MISO on SPI3 
#define MISO  37                //MOSI on SPI3
#define SS    38

File root;

void setup() {
  Serial.begin(115200);

  SPI.begin(SCK, MISO, MOSI, SS);
  
  Serial.print("Initializing SD card... ");

  if (!SD.begin(SS)) {
    Serial.println("Card initialization failed!");
    while (true);
  }

  Serial.println("initialization done.");

  Serial.println("Files in the card:");
  root = SD.open("/");
  printDirectory(root, 0);
  Serial.println("");
}

void loop() {
  // put your main code here, to run repeatedly:
  delay(10); // this speeds up the simulation
}

void printDirectory(File dir, int numTabs) {
  while (true) {

    File entry =  dir.openNextFile();
    if (! entry) {
      // no more files
      break;
    }
    for (uint8_t i = 0; i < numTabs; i++) {
      Serial.print('\t');
    }
    Serial.print(entry.name());
    if (entry.isDirectory()) {
      Serial.println("/");
      printDirectory(entry, numTabs + 1);
    } else {
      // files have sizes, directories do not
      Serial.print("\t\t");
      Serial.println(entry.size(), DEC);
    }
    entry.close();
  }
}