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Little-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 order of their addresses in memory - for instance the double word integer 16909060 or 0x01020304.
Little-Endian, little-end first (left, top)

Memory layout

0x01020304
Address
Byte
Significance
0x0000
0x04
LS Byte
0x0001
0x03

0x0002
0x02

0x0003
0x01
MS Byte

Runtime Test

Following C-routine returns "true" on little-endian machines, such as Intel x86:
bool isLittleEndian() {
   short one = 0x0001; // 16 bit
   return (bool) (*(char*)&one);
}

Little-Endian Files

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

Little-Endian Ranks

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

Least Significant Files

squareIndex = 8*rankIndex + fileIndex
rankIndex   = squareIndex div 8
fileIndex   = squareIndex mod 8
The LERF-coordianetes with Little-Endian Files and Little-Endian Ranks:
enum enumSquare {
  a1, b1, c1, d1, e1, f1, g1, h1, //  0 ..  7
  a2, b2, c2, d2, e2, f2, g2, h2, //  8 .. 15
  a3, b3, c3, d3, e3, f3, g3, h3, // 16 .. 23
  a4, b4, c4, d4, e4, f4, g4, h4, // 24 .. 31
  a5, b5, c5, d5, e5, f5, g5, h5, // 32 .. 39
  a6, b6, c6, d6, e6, f6, g6, h6, // 40 .. 47
  a7, b7, c7, d7, e7, f7, g7, h7, // 48 .. 55
  a8, b8, c8, d8, e8, f8, g8, h8  // 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 | 57 | 58 | 59 | 60 | 61 | 62 | 63 |  8th rank
   +----+----+----+----+----+----+----+----+
 7 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 |  7th rank
   +----+----+----+----+----+----+----+----+
 6 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 |  6th rank
   +----+----+----+----+----+----+----+----+
 5 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 |  5th rank
   +----+----+----+----+----+----+----+----+
 4 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 |  4th rank
   +----+----+----+----+----+----+----+----+
 3 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 |  3rd rank
   +----+----+----+----+----+----+----+----+
 2 |  8 |  9 | 10 | 11 | 12 | 13 | 14 | 15 |  2nd rank
   +----+----+----+----+----+----+----+----+
 1 |  0 |  1 |  2 |  3 |  4 |  5 |  6 |  7 |  1st rank
   +----+----+----+----+----+----+----+----+
     A    B    C    D    E    F    G    H - file(s)

Date-Format

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

See also


External Links


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