Diamond for Atari 8-bit computers in 6502 assembly

Author: dmsc
Category: Christmas Challenge
System:   Atari 8-bit
Language: Assembler
Len source code: 662
Len exe file:    35
Len code only:   29
Instructions:
  With the provided ATR floppy disk image, just boot and type DIAMOND to run
  the program.

Description:
  This program uses a table with values:

    Table[] = 0  1  2  3  2  1  0  1  2  3  2  1  0  1  2  3  2 ...

  Then, for each coordinate (X,Y), we draw a star where Table[X] == Table[Y+3]

  The table is stored at the start of the code, using the first few
  instructions, and is expanded on use.

  To assemble the program, you can use the MADS assembler.

Comments:
  To minimize size, this program directly calls the OS editor PUT routine, this
  means it is only compatible with the XL OS used in Atari XL and XE computers.