map 0x00-0xD7, 0x00-0xFF to U+0000 using big-endian
map 0xE0-0xFF, 0x00-0xFF to U+E000 using big-endian
map 0xD8-0xDB, 0x00-0xFF,\
    0xDC-0xDF, 0x00-0xFF to U+010000 using big-endian