Wio LTE for Arduino에서 SD 카드 사용

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SDReadWrite.ino

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sd_test/sd_test.ino

// ---------------------------------------------------------------
/*
    sd_test.ino

                    Jul/30/2021
*/
// ---------------------------------------------------------------
#include <SDforWioLTE.h>

#define FILE_NAME "test_cc.txt"

// ---------------------------------------------------------------
void setup()
{
    delay(1000);
    SerialUSB.println("*** sd_test *** setup *** aaa ***");
    delay(1000);
    SerialUSB.println("*** sd_test *** setup *** bbb ***");
    delay(1000);
    SerialUSB.println("*** sd_test *** setup *** ccc ***");

    SerialUSB.println("");
    SerialUSB.println("*** START ***");

    SerialUSB.println("### Initialize SD card.");
    if (!SD.begin()) {
        SerialUSB.println("### ERROR! SD.begin ###");
        }
    else
        {
    file_write_proc();
    file_read_proc();
        }

    SerialUSB.println("*** Setup completed ***");
}

// ---------------------------------------------------------------
void loop()
{
    SerialUSB.println("*** loop *** aaa ***");
    delay(3000);
    SerialUSB.println("*** loop *** bbb ***");
    delay(3000);
}

// ---------------------------------------------------------------
void file_write_proc()
{
    File myFile_out;

    SerialUSB.println("### Writing to "FILE_NAME".");

    if (SD.exists(FILE_NAME))
        {
        SD.remove(FILE_NAME);
        }

    myFile_out = SD.open(FILE_NAME, FILE_WRITE);
    if (!myFile_out)
        {
        SerialUSB.println("### ERROR! SD.open ###");
        }
    else
        {
        myFile_out.println("testing 1, 2, 3, 4, 5.");
        myFile_out.println("Good Morning.");
        myFile_out.println("Good Afternoon.");
        myFile_out.println("Good Night.");
        myFile_out.println("Jul/30/2021 PM 20:00");
        myFile_out.close();
        }
}

// ---------------------------------------------------------------
void file_read_proc()
{
    File myFile_in;

    SerialUSB.println("### Reading from "FILE_NAME".");
    myFile_in = SD.open(FILE_NAME);
    if (!myFile_in) {
        SerialUSB.println("### ERROR! SD.open ###");
    }
    else
        {
        SerialUSB.println(FILE_NAME":");
        while (myFile_in.available()) {
            SerialUSB.write(myFile_in.read());
            }
        myFile_in.close();
        }
}

// ---------------------------------------------------------------

실행 결과