The LTDEF variable - Elite on the BBC Micro

       Name: LTDEF                                                   [Show more]
       Type: Variable
   Category: Demo
    Summary: Line definitions for characters in the Star Wars scroll text
  Deep dive: The 6502 Second Processor demo mode
    Context: See this variable in context in the source code
 References: This variable is used as follows:
             * GRIDSET uses LTDEF


 Characters in the scroll text are drawn using lines on a 3x6 numbered grid
 like this:

   0   1   2
   .   .   .
   3   4   5
   .   .   .
   6   7   8
   9   A   B

 The low nibble of each byte is the starting point for that line segment, and
 the high nibble is the end point, so a value of &28, for example, means
 "draw a line from point 8 to point 2". This table contains definitions for all
 the characters we can use in the scroll text, as lines on the above grid.

 See the deep dive on "the 6502 Second Processor demo mode" for details.


.LTDEF

 EQUB &63, &34, &47, &76, &97   \ Letter definition for ","
 EQUB &35, &00, &00, &00, &00   \ Letter definition for "-"
 EQUB &63, &34, &47, &76, &00   \ Letter definition for "."
 EQUB &61, &00, &00, &00, &00   \ Letter definition for "/"
 EQUB &73, &31, &15, &57, &00   \ Letter definition for "0"
 EQUB &31, &17, &00, &00, &00   \ Letter definition for "1"
 EQUB &02, &25, &53, &36, &68   \ Letter definition for "2"
 EQUB &02, &28, &86, &35, &00   \ Letter definition for "3"
 EQUB &82, &23, &35, &00, &00   \ Letter definition for "4"
 EQUB &20, &03, &35, &58, &86   \ Letter definition for "5"
 EQUB &20, &06, &68, &85, &53   \ Letter definition for "6"
 EQUB &02, &28, &00, &00, &00   \ Letter definition for "7"
 EQUB &60, &02, &28, &86, &35   \ Letter definition for "8"
 EQUB &82, &20, &03, &35, &00   \ Letter definition for "9"
 EQUB &00, &00, &00, &00, &00   \ Letter definition for ":" (blank)
 EQUB &00, &00, &00, &00, &00   \ Letter definition for ";" (blank)
 EQUB &00, &00, &00, &00, &00   \ Letter definition for "<" (blank)
 EQUB &00, &00, &00, &00, &00   \ Letter definition for "=" (blank)
 EQUB &00, &00, &00, &00, &00   \ Letter definition for ">" (blank)
 EQUB &00, &00, &00, &00, &00   \ Letter definition for "?" (blank)
 EQUB &00, &00, &00, &00, &00   \ Letter definition for "@" (blank)
 EQUB &60, &02, &28, &35, &00   \ Letter definition for "A"
 EQUB &60, &02, &28, &86, &35   \ Letter definition for "B"
 EQUB &86, &60, &02, &00, &00   \ Letter definition for "C"
 EQUB &60, &05, &56, &00, &00   \ Letter definition for "D"
 EQUB &86, &60, &02, &35, &00   \ Letter definition for "E"
 EQUB &60, &02, &35, &00, &00   \ Letter definition for "F"
 EQUB &45, &58, &86, &60, &02   \ Letter definition for "G"
 EQUB &60, &28, &35, &00, &00   \ Letter definition for "H"
 EQUB &17, &00, &00, &00, &00   \ Letter definition for "I"
 EQUB &28, &86, &63, &00, &00   \ Letter definition for "J"
 EQUB &60, &23, &83, &00, &00   \ Letter definition for "K"
 EQUB &86, &60, &00, &00, &00   \ Letter definition for "L"
 EQUB &60, &04, &42, &28, &00   \ Letter definition for "M"
 EQUB &60, &08, &82, &00, &00   \ Letter definition for "N"
 EQUB &60, &02, &28, &86, &00   \ Letter definition for "O"
 EQUB &60, &02, &25, &53, &00   \ Letter definition for "P"
 EQUB &60, &02, &28, &86, &48   \ Letter definition for "Q"
 EQUB &60, &02, &25, &53, &48   \ Letter definition for "R"
 EQUB &20, &03, &35, &58, &86   \ Letter definition for "S"
 EQUB &02, &17, &00, &00, &00   \ Letter definition for "T"
 EQUB &28, &86, &60, &00, &00   \ Letter definition for "U"
 EQUB &27, &70, &00, &00, &00   \ Letter definition for "V"
 EQUB &28, &84, &46, &60, &00   \ Letter definition for "W"
 EQUB &26, &08, &00, &00, &00   \ Letter definition for "X"
 EQUB &74, &04, &24, &00, &00   \ Letter definition for "Y"
 EQUB &02, &26, &68, &00, &00   \ Letter definition for "Z"
Demo: LTDEF

[6502 Second Processor version]
