Decoding Repton Decoding Repton Compiled by Gerald J Holdsworth Compiled by Gerald J Holdsworth Page 1 22 December 2017 Decoding Repton Contents Introduction ........................................................................... 5 Conventions and Nomenclature ............................................. 6 Keywords .................................................................................................... 6 Numeric Notation ....................................................................................... 6 Endian Notation .......................................................................................... 6 How The Maps Are Stored ...................................................... 7 Method One ................................................................................................ 7 Method Two ............................................................................................... 7 How The Graphics Are Stored ................................................. 8 BBC Micro/Acorn Electron ........................................................................... 8 Commodore 64 ........................................................................................... 8 ZX Spectrum ................................................................................................ 8 Archimedes/RISC OS ................................................................................... 9 BBC and Electron Repton ...................................................... 10 File Format (BBC) ...................................................................................... 10 File Format (Electron) ................................................................................ 10 Characters ................................................................................................ 10 Maps ........................................................................................................ 11 Map Characters ........................................................................................ 11 Passwords ................................................................................................. 11 Palette ...................................................................................................... 11 Time Limits ............................................................................................... 11 Desktop Repton .................................................................... 12 Encryption Key .......................................................................................... 12 File Layout ................................................................................................ 13 Characters ................................................................................................ 13 Archimedes and RiscPC Repton ............................................ 14 File Layout ................................................................................................ 14 Characters ................................................................................................ 14 Maps ........................................................................................................ 14 Time Limits ............................................................................................... 14 Passwords ................................................................................................. 14 Palette ...................................................................................................... 14 BBC and Electron Repton 2 ................................................... 15 File Layout (BBC) ....................................................................................... 15 File Layout (Electron, DFS format) ............................................................. 15 Level Data ................................................................................................. 15 Puzzle Piece Definitions ............................................................................. 16 Transporters ............................................................................................. 16 Compiled by Gerald J Holdsworth Page 2 22 December 2017 Decoding Repton Start Position ............................................................................................ 16 Palette ...................................................................................................... 16 Game Sprites and Puzzle Piece Sprites ....................................................... 16 Desktop Repton 2 ................................................................. 18 Encryption Key .......................................................................................... 18 File Format ............................................................................................... 19 Co-ordinates ............................................................................................. 19 Maps ........................................................................................................ 19 Edges ........................................................................................................ 19 Palette ...................................................................................................... 19 Puzzle Pieces ............................................................................................. 19 Transporters ............................................................................................. 19 Characters ................................................................................................ 19 Archimedes and RiscPC Repton 2 .......................................... 21 File Format (Archimedes) .......................................................................... 21 File Format (RiscPC) .................................................................................. 21 Maps ........................................................................................................ 21 Edges ........................................................................................................ 21 Characters ................................................................................................ 21 Transporters ............................................................................................. 21 Puzzle Pieces ............................................................................................. 21 Palette ...................................................................................................... 22 Repton 3 ............................................................................... 23 File Layout (BBC/Electron) ......................................................................... 23 File Layout (Archimedes/Desktop Repton) ................................................. 23 File Layout (Commodore) .......................................................................... 23 Passwords ................................................................................................. 24 Edit Codes ................................................................................................. 24 Time Limits ............................................................................................... 24 Transporters ............................................................................................. 24 Colour Palette ........................................................................................... 25 Maps ........................................................................................................ 25 Characters ................................................................................................ 25 Competition Codes .................................................................................... 25 Repton Infinity ..................................................................... 27 G.game format ......................................................................................... 27 eG.game format ....................................................................................... 27 E.game file format .................................................................................... 28 M.game format ........................................................................................ 28 S.game file format .................................................................................... 28 eS.game file format .................................................................................. 28 O.game file format ................................................................................... 29 T.game file format .................................................................................... 31 Passwords ................................................................................................. 32 Compiled by Gerald J Holdsworth Page 3 22 December 2017 Decoding Repton Sinclair ZX Spectrum Repton Mania ...................................... 33 DSK and Memory Usage ............................................................................ 33 Maps ........................................................................................................ 34 Transporters, Puzzle Pieces and Spirits ...................................................... 34 Z80 format ................................................................................................ 35 EGO: Repton 4 .....................................................................