Arduino: Base64.h の使い方

// ---------------------------------------------------------------
/*
    base64_test.ino

                        Aug/15/2021
*/
// ---------------------------------------------------------------
#include <Base64.h>

// ---------------------------------------------------------------
void setup()
{
  Serial.begin(19200);
    delay (1000);
    Serial.println("*** start ***");
    delay(500);
    Serial.println("*** Base64 example ***");
    delay(500);

    char Buf[50];

    int llx = 8;
    String str_array[] = {"A","AB","ABC","ABCD","ABCDE","ABCDEF","ABCDEFG",
        "ABCDEFGH"};


Serial.println ("llx = " + String(llx));
delay(1000);

 for (int itt=0; itt < llx; itt++)
 {
        str_array[itt].toCharArray(Buf, 50);    
        String str_encoded = encode_proc(Buf);
        Serial.println(str_encoded);

   delay(300);
        }

    delay(500);
    Serial.println("*** setup *** end ***");
}

// ---------------------------------------------------------------
String encode_proc(char* input)
{
    Serial.println(input);

    int inputLen = strlen(input);

    int encodedLen = Base64.encodedLength(inputLen);
    char encoded[encodedLen];

    Base64.encode(encoded, input, inputLen); 

    return String(encoded);
}

// ---------------------------------------------------------------
void loop()
{
    Serial.println("*** loop ***");
    delay (3000); 
}

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

*** start ***
*** Base64 example ***
llx = 8
A
QQ==
AB
QUI=
ABC
QUJD
ABCD
QUJDRA==
ABCDE
QUJDREU=
ABCDEF
QUJDREVG
ABCDEFG
QUJDREVGRw==
ABCDEFGH
QUJDREVGR0g=
*** setup *** end ***
*** loop ***