Big-endian

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Big-endian is most often referred to the endianness or order of multiple Bytes inside a composite item, such as a Word (two bytes), a Double Word (four bytes) or a Quad Word (eight bytes), which keeps the byte order (in the arithmetical sense) in the reverse order of their addresses in memory - for instance the integer 16909060 or 0x01020304.

Memory layout

0x01020304

Address	Byte	Significance
0x0000	0x01	MS Byte
0x0001	0x02
0x0002	0x03
0x0003	0x04	LS Byte

Big-Endian Files

File index 0 maps the H-File, index 7 the A-File.

Big-Endian Ranks

Rank index 0 maps the eight Rank, index 7 the first Rank.

Least Significant Ranks

• Files are the big-end over ranks:

squareIndex = 8*fileIndex + rankIndex
fileIndex   = squareIndex div 8
rankIndex   = squareIndex mod 8

The BERF-coordinates with Big-endian Files and Big-endian Ranks:

enum enumSquare {
  h8, h7, h6, h5, h4, h3, h2, h1, //  0 ..  7
  g8, g7, g6, g5, g4, g3, g2, g1, //  8 .. 15
  f8, f7, f6, f5, f4, f3, f2, f1, // 16 .. 23
  e8, e7, e6, e5, e4, e3, e2, e1, // 24 .. 31
  d8, d7, d6, d5, d4, d3, d2, d1, // 32 .. 39
  c8, c7, c6, c5, c4, c3, c2, c1, // 40 .. 47
  b8, b7, b6, b5, b4, b3, b2, b1, // 48 .. 55
  a8, a7, a6, a5, a4, a3, a2, a1, // 56 .. 63
};

Note: If printing boards from top to bottom, one has to start with the big-end rank.

     A    B    C    D    E    F    G    H
   +----+----+----+----+----+----+----+----+
 8 | 56 | 48 | 40 | 32 | 24 | 16 |  8 |  0 |  8th rank
   +----+----+----+----+----+----+----+----+
 7 | 57 | 49 | 41 | 33 | 25 | 17 |  9 |  1 |  7th rank
   +----+----+----+----+----+----+----+----+
 6 | 58 | 50 | 42 | 34 | 26 | 18 | 10 |  2 |  6th rank
   +----+----+----+----+----+----+----+----+
 5 | 59 | 51 | 43 | 35 | 27 | 19 | 11 |  3 |  5th rank
   +----+----+----+----+----+----+----+----+
 4 | 60 | 52 | 44 | 36 | 28 | 20 | 12 |  4 |  4th rank
   +----+----+----+----+----+----+----+----+
 3 | 61 | 53 | 45 | 37 | 29 | 21 | 13 |  5 |  3rd rank
   +----+----+----+----+----+----+----+----+
 2 | 62 | 54 | 46 | 38 | 30 | 22 | 14 |  6 |  2nd rank
   +----+----+----+----+----+----+----+----+
 1 | 63 | 55 | 47 | 39 | 31 | 23 | 15 |  7 |  1st rank
   +----+----+----+----+----+----+----+----+
     A    B    C    D    E    F    G    H - file(s)

Date-Format

The big-endian date format: yyyy-mm-dd.

See also

• Little-endian
• Square Mapping Considerations
• Flipping Mirroring and Rotating
• Word
• Double Word
• Quad Word

External Links

• Endianness from Wikipedia
• IEN 137 - DAV's Endian FAQ - On Holy Wars and a Plea for Peace by Danny Cohen, USC/ISI, April 1, 1980

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