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For text-mode files, carriage return–linefeed pairs are counted as single characters.

对文本模式的文件，换行作为一字符。

Please press enter key when you see the main menu on the screen.

屏幕上出现主菜单时键。

Serial.print(b, BYTE) prints b as a single byte followed by a carriage return and a linefeed.

以单字节出b，并同时跟随一和换行符。