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@nazt
Created March 31, 2020 15:33
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sdcard-test.ino
#include <mySD.h>
#define LED_BUILTIN 22 //Blink pin
File root;
void setup()
{
Serial.begin(115200);
pinMode(LED_BUILTIN, OUTPUT);
Serial.print("Initializing SD card...");
/* initialize SD library with SPI pins */
if (!SD.begin(13, 15, 2, 14)) { //T1:13,15,2,14 T2: 23,5,19,18 M5:4,23,19,18 uint8_t csPin, int8_t mosi, int8_t miso, int8_t sck
Serial.println("initialization failed!");
return;
}
Serial.println("initialization done.");
/* Begin at the root "/" */
root = SD.open("/");
if (root) {
printDirectory(root, 0);
root.close();
} else {
Serial.println("error opening test.txt");
}
/* open "test.txt" for writing */
root = SD.open("test.txt", FILE_WRITE);
/* if open succesfully -> root != NULL
then write string "Hello world!" to it
*/
if (root) {
root.println("Hello world!");
root.flush();
/* close the file */
root.close();
} else {
/* if the file open error, print an error */
Serial.println("error opening test.txt");
}
delay(1000);
/* after writing then reopen the file and read it */
root = SD.open("test.txt");
if (root) {
/* read from the file until there's nothing else in it */
while (root.available()) {
/* read the file and print to Terminal */
Serial.write(root.read());
}
root.close();
} else {
Serial.println("error opening test.txt");
}
Serial.println("done!");
}
void loop()
{
digitalWrite(LED_BUILTIN, HIGH); // turn the LED on (HIGH is the voltage level)
delay(1000); // wait for a second
digitalWrite(LED_BUILTIN, LOW); // turn the LED off by making the voltage LOW
delay(1000); // wait for a second
}
void printDirectory(File dir, int numTabs) {
while (true) {
File entry = dir.openNextFile();
if (! entry) {
break;
}
for (uint8_t i = 0; i < numTabs; i++) {
Serial.print('\t'); // we'll have a nice indentation
}
// Print the name
Serial.print(entry.name());
/* Recurse for directories, otherwise print the file size */
if (entry.isDirectory()) {
Serial.println("/");
printDirectory(entry, numTabs + 1);
} else {
/* files have sizes, directories do not */
Serial.print("\t\t");
Serial.println(entry.size());
}
entry.close();
}
}
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