Some Morse Tutor projects are adding SD card support (the text file on the SD Card is sent via Morse Code).
I went to gutenberg.org and loaded a large Sherlock Holmes book onto a Samsung 32 GB EVO Plus MicroSDHC UHS-1 Card. Formatted with PC/MAC app SDFORMATTER for Type1 SDHC FAT32
Inserted the card into the M5Stack SD card socket and had no trouble reading/writing it with this code:
#include <M5Stack.h>
//Micro SD / TF Card Test
/*
M5Stack initializing...OK
Listing directory: /
DIR : /.Spotlight-V100
DIR : /.fseventsd
FILE: /SherlockHolmes.txt SIZE: 590492
FILE: /._SherlockHolmes.txt SIZE: 4096
FILE: /hello.txt SIZE: 11
Writing file: /hello.txt
File written
Reading file: /hello.txt
Read from file: Hello world from M5Stack !!
*/
void listDir(fs::FS &fs, const char * dirname, uint8_t levels){
// Print blank line on screen
M5.Lcd.printf(" \n ");
M5.Lcd.printf(" \n ");
Serial.printf("Listing directory: %s\n", dirname);
M5.Lcd.printf("Listing directory: %s\n", dirname);
File root = fs.open(dirname);
if(!root){
Serial.println("Failed to open directory");
M5.Lcd.println("Failed to open directory");
return;
}
if(!root.isDirectory()){
Serial.println("Not a directory");
M5.Lcd.println("Not a directory");
return;
}
File file = root.openNextFile();
while(file){
if(file.isDirectory()){
Serial.print(" DIR : ");
M5.Lcd.print(" DIR : ");
Serial.println(file.name());
M5.Lcd.println(file.name());
if(levels){
listDir(fs, file.name(), levels -1);
}
} else {
Serial.print(" FILE: ");
M5.Lcd.print(" FILE: ");
Serial.print(file.name());
M5.Lcd.print(file.name());
Serial.print(" SIZE: ");
M5.Lcd.print(" SIZE: ");
Serial.println(file.size());
M5.Lcd.println(file.size());
}
file = root.openNextFile();
}
}
void readFile(fs::FS &fs, const char * path) {
Serial.printf("Reading file: %s\n", path);
M5.Lcd.printf("Reading file: %s\n", path);
File file = fs.open(path);
if(!file){
Serial.println("Failed to open file for reading");
M5.Lcd.println("Failed to open file for reading");
return;
}
Serial.print("Read from file: ");
M5.Lcd.print("Read from file: ");
while(file.available()){
int ch = file.read();
Serial.write(ch);
M5.Lcd.write(ch);
}
}
void writeFile(fs::FS &fs, const char * path, const char * message){
Serial.printf("Writing file: %s\n", path);
M5.Lcd.printf("Writing file: %s\n", path);
File file = fs.open(path, FILE_WRITE);
if(!file){
Serial.println("Failed to open file for writing");
M5.Lcd.println("Failed to open file for writing");
return;
}
if(file.print(message)){
Serial.println("File written");
M5.Lcd.println("File written");
} else {
Serial.println("Write failed");
M5.Lcd.println("Write failed");
}
}
// the setup routine runs once when M5Stack starts up
void setup() {
// initialize the M5Stack object
M5.begin();
//M5.startupLogo();
Wire.begin();
// Lcd display
M5.Lcd.setBrightness(100);
M5.Lcd.fillScreen(BLACK);
M5.Lcd.setCursor(0, 10);
M5.Lcd.setTextColor(WHITE);
M5.Lcd.setTextSize(1);
// Page Header
M5.Lcd.fillScreen(BLACK);
M5.Lcd.setCursor(0, 05);
M5.Lcd.printf(" Testing Micro SD Card Functions:\r\n");
// digitalWrite(TFT_CS, 1);
// Print blank line on screen
M5.Lcd.printf(" \n ");
M5.Lcd.printf(" \n ");
listDir(SD, "/", 0);
M5.Lcd.printf("");
M5.Lcd.printf("");
// Print blank line on screen
M5.Lcd.printf(" \n ");
M5.Lcd.printf(" \n ");
writeFile(SD, "/hello.txt", "Hello world from M5Stack !!");
M5.Lcd.printf("");
M5.Lcd.printf("");
// Print blank line on screen
M5.Lcd.printf(" \n ");
M5.Lcd.printf(" \n ");
// Print blank line on screen
M5.Lcd.printf(" \n ");
M5.Lcd.printf(" \n ");
readFile(SD, "/hello.txt");
}
void loop() {
// put your main code here, to run repeatedly:
M5.update();
}
wm6h 