SDCard

案例程序

#include <M5Cardputer.h>
#include <SPI.h>
#include <SD.h>

#define SD_SPI_SCK_PIN  40
#define SD_SPI_MISO_PIN 39
#define SD_SPI_MOSI_PIN 14
#define SD_SPI_CS_PIN   12

void listDir(fs::FS &fs, const char *dirname, uint8_t levels);
void createDir(fs::FS &fs, const char *path);
void removeDir(fs::FS &fs, const char *path);
void readFile(fs::FS &fs, const char *path);
void writeFile(fs::FS &fs, const char *path, const char *message);
void appendFile(fs::FS &fs, const char *path, const char *message);
void renameFile(fs::FS &fs, const char *path1, const char *path2);
void deleteFile(fs::FS &fs, const char *path);
void testFileIO(fs::FS &fs, const char *path);

M5Canvas canvas(&M5Cardputer.Display);

void printf_log(const char *format, ...);
void println_log(const char *str);

void setup() {
    M5Cardputer.begin();
    M5Cardputer.Display.setRotation(1);
    canvas.setColorDepth(1);  // mono color
    canvas.createSprite(M5Cardputer.Display.width(),
                        M5Cardputer.Display.height());
    canvas.setPaletteColor(1, GREEN);
    canvas.setTextSize((float)canvas.width() / 160);
    canvas.setTextScroll(true);

    // SD Card Initialization
    SPI.begin(SD_SPI_SCK_PIN, SD_SPI_MISO_PIN, SD_SPI_MOSI_PIN, SD_SPI_CS_PIN);

    if (!SD.begin(SD_SPI_CS_PIN, SPI, 25000000)) {
        // Print a message if the SD card initialization
        // fails orif the SD card does not exist.
        // 如果SD卡初始化失败或者SD卡不存在，则打印消息.
        println_log("Card failed, or not present");
        while (1)
            ;
    }

    uint8_t cardType = SD.cardType();

    if (cardType == CARD_NONE) {
        println_log("No SD card attached");
        return;
    }

    Serial.print("SD Card Type: ");
    if (cardType == CARD_MMC) {
        println_log("MMC");
    } else if (cardType == CARD_SD) {
        println_log("SDSC");
    } else if (cardType == CARD_SDHC) {
        println_log("SDHC");
    } else {
        println_log("UNKNOWN");
    }

    uint64_t cardSize = SD.cardSize() / (1024 * 1024);
    printf_log("SD Card Size: %lluMB\n", cardSize);

    listDir(SD, "/", 0);
    createDir(SD, "/mydir");
    listDir(SD, "/", 0);
    removeDir(SD, "/mydir");
    listDir(SD, "/", 2);
    writeFile(SD, "/hello.txt", "Hello ");
    appendFile(SD, "/hello.txt", "World!\n");
    readFile(SD, "/hello.txt");
    deleteFile(SD, "/foo.txt");
    renameFile(SD, "/hello.txt", "/foo.txt");
    readFile(SD, "/foo.txt");
    testFileIO(SD, "/test.txt");
    printf_log("Total space: %lluMB\n", SD.totalBytes() / (1024 * 1024));
    printf_log("Used space: %lluMB\n", SD.usedBytes() / (1024 * 1024));
}
void loop() {
}

void listDir(fs::FS &fs, const char *dirname, uint8_t levels) {
    printf_log("Listing directory: %s\n", dirname);

    File root = fs.open(dirname);
    if (!root) {
        println_log("Failed to open directory");
        return;
    }
    if (!root.isDirectory()) {
        println_log("Not a directory");
        return;
    }

    File file = root.openNextFile();
    while (file) {
        if (file.isDirectory()) {
            Serial.print("  DIR : ");
            println_log(file.name());
            if (levels) {
                listDir(fs, file.path(), levels - 1);
            }
        } else {
            Serial.print("  FILE: ");
            Serial.print(file.name());
            Serial.print("  SIZE: ");
            println_log(String(file.size()).c_str());
        }
        file = root.openNextFile();
    }
}

void createDir(fs::FS &fs, const char *path) {
    printf_log("Creating Dir: %s\n", path);
    if (fs.mkdir(path)) {
        println_log("Dir created");
    } else {
        println_log("mkdir failed");
    }
}

void removeDir(fs::FS &fs, const char *path) {
    printf_log("Removing Dir: %s\n", path);
    if (fs.rmdir(path)) {
        println_log("Dir removed");
    } else {
        println_log("rmdir failed");
    }
}

void readFile(fs::FS &fs, const char *path) {
    printf_log("Reading file: %s\n", path);

    File file = fs.open(path);
    if (!file) {
        println_log("Failed to open file for reading");
        return;
    }

    Serial.print("Read from file: ");
    while (file.available()) {
        Serial.write(file.read());
    }
    file.close();
}

void writeFile(fs::FS &fs, const char *path, const char *message) {
    printf_log("Writing file: %s\n", path);

    File file = fs.open(path, FILE_WRITE);
    if (!file) {
        println_log("Failed to open file for writing");
        return;
    }
    if (file.print(message)) {
        println_log("File written");
    } else {
        println_log("Write failed");
    }
    file.close();
}

void appendFile(fs::FS &fs, const char *path, const char *message) {
    printf_log("Appending to file: %s\n", path);

    File file = fs.open(path, FILE_APPEND);
    if (!file) {
        println_log("Failed to open file for appending");
        return;
    }
    if (file.print(message)) {
        println_log("Message appended");
    } else {
        println_log("Append failed");
    }
    file.close();
}

void renameFile(fs::FS &fs, const char *path1, const char *path2) {
    printf_log("Renaming file %s to %s\n", path1, path2);
    if (fs.rename(path1, path2)) {
        println_log("File renamed");
    } else {
        println_log("Rename failed");
    }
}

void deleteFile(fs::FS &fs, const char *path) {
    printf_log("Deleting file: %s\n", path);
    if (fs.remove(path)) {
        println_log("File deleted");
    } else {
        println_log("Delete failed");
    }
}

void testFileIO(fs::FS &fs, const char *path) {
    File file = fs.open(path);
    static uint8_t buf[512];
    size_t len     = 0;
    uint32_t start = millis();
    uint32_t end   = start;
    if (file) {
        len         = file.size();
        size_t flen = len;
        start       = millis();
        while (len) {
            size_t toRead = len;
            if (toRead > 512) {
                toRead = 512;
            }
            file.read(buf, toRead);
            len -= toRead;
        }
        end = millis() - start;
        printf_log("%u bytes read for %lu ms\n", flen, end);
        file.close();
    } else {
        println_log("Failed to open file for reading");
    }

    file = fs.open(path, FILE_WRITE);
    if (!file) {
        println_log("Failed to open file for writing");
        return;
    }

    size_t i;
    start = millis();
    for (i = 0; i < 2048; i++) {
        file.write(buf, 512);
    }
    end = millis() - start;
    printf_log("%u bytes written for %lu ms\n", 2048 * 512, end);
    file.close();
}

void printf_log(const char *format, ...) {
    char buf[256];
    va_list args;
    va_start(args, format);
    vsnprintf(buf, 256, format, args);
    va_end(args);
    Serial.print(buf);
    canvas.printf(buf);
    canvas.pushSprite(0, 0);
}

void println_log(const char *str) {
    Serial.println(str);
    canvas.println(str);
    canvas.pushSprite(0, 0);
}