Ascii Chess

Ascii chess can help understand PGN (portable game notation) and FEN (Forsyth-Edwards Notation), and can assist in developing the mental imagery for blindfold chess, memory of positions and games, and positional lookahead. This page serves as an introductory manual for the Ascii application displayed below, also accessible at https://josh-b-merrell.shinyapps.io/my-chess/):

Basic Usage

Submit/Undo Moves

Below the Ascii View is a dropdown and an input box for submitting moves. The Undo button undoes the last move. The Submit Move button submits the contents of the input box. The input box can be manually edited or populated from the dropdown box.

The dropdown box might be helpful in cases where, for example, two black knights are located on b8 and f6 and can move to d7. In this case, the proper notation for moving knight to d7 is Nbd7 or Nfd7 rather than simply Nd7. In such cases, guessing the correct input can be frustrating.

Move History

The move history is a form of PGN (portable game notation), though PGN is not as standardized as FEN (see list of other notation examples below). Unlike FEN, PGN capitalizes pieces of both colors to distinguish from files/columns of squares (if no piece is specified, it is a pawn). For the history,

e4 e4 Bd3 Nh6:

The notation specifies the piece names (or lack thereof for pawns) and their destinations, and leaves the move numbers, colors, origin squares, and other details to be infered as follows:

┌───────────────────────────┬┬───────────────────────────────────┐
│written                    ││                           inferred│
├────────┬──────┬───────────┼┼────────┬─────┬──────┬─────────────┤
│notation│piece │destination││fullmove│color│origin│other        │
├────────┼──────┼───────────┼┼────────┼─────┼──────┼─────────────┤
│e4      │pawn  │e4         ││1       │white│e2    │en passant=e3│
├────────┼──────┼───────────┼┼────────┼─────┼──────┼─────────────┤
│e5      │pawn  │e5         ││1       │black│e7    │en passant=e6│
├────────┼──────┼───────────┼┼────────┼─────┼──────┼─────────────┤
│Bd3     │bishop│d3         ││2       │white│f1    │             │
├────────┼──────┼───────────┼┼────────┼─────┼──────┼─────────────┤
│Nh6     │knight│h6         ││2       │black│h7    │             │
└────────┴──────┴───────────┴┴────────┴─────┴──────┴─────────────┘

Some other notations for displaying this same history are:

The correct notation to use is context-dependent. The least verbose option currently fits my purposes for Ascii Chess.

Ascii board

The Ascii board shows white pieces as capitalized and black pieces as lowercase.

┌──────┬─────┬─────┐
│Piece │White│Black│
├──────┼─────┼─────┤
│Pawn  │P    │p    │
├──────┼─────┼─────┤
│Knight│N    │n    │
├──────┼─────┼─────┤
│Bishop│B    │b    │
├──────┼─────┼─────┤
│Rook  │R    │r    │
├──────┼─────┼─────┤
│Queen │Q    │q    │
├──────┼─────┼─────┤
│King  │K    │k    │
└──────┴─────┴─────┘

FEN string

FEN stands for Forsyth-Edwards Notation, and its Wikipedia page is highly informative. The FEN consists of 6 fields separated by spaces. The first field is separated into 8 subfields separated by forward-slashes, depicting ranks.

 1 - Piece Placement                         2  3   4 5 6 
┌───────────────────────────────────────────┬─┬────┬─┬─┬─┐
 rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
└────────┴────────┴─┴─┴─┴─┴────────┴────────┘
 rank 8   rank 7   6 5 4 3   rank 2   rank 1

These fields can be labelled:

  1. Piece Placement
  2. Active color (whose turn it is) w ~ white; b ~ black
  3. Castling availability
  4. En Passant target square (- if none)
  5. Halfmove Clock for (fifty-move rule)[https://en.wikipedia.org/wiki/Fifty-move_rule]
  6. Fullmove number - the number of full moves starting at 1 and incrementing after Black’s moves.