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115 191 bytes (112.49K)
File date:
2025-12-30 23:34:07
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  • file_id.diz 851B
  • result.png 717B
  • snowflake.asm 2.30K
  • snowflake.prg 86B
  • source.png 112.66K

file_id.diz

Snowflake (MEGA65/4510 Assembler)

Author: Geir Straume
Category: Christmas Challenge
System: MEGA65
Language: Assembler (ACME)
Len source code: 2358 bytes (source with comments)
Len exe file:    86 bytes
Len code only:   68 bytes (excl. load address and BASIC stub)
Instructions:
Install the Xemu emulator (https://github.lgb.hu/xemu/) with a recent MEGA65 ROM version.
Drag and drop "snowflake.prg" into the emulator window.

Description:
The program contains ten bytes of bit patterns which are used to display the rows of the snowflake on screen.

Each byte is rotated left for the left part of a row, and then right for the right part. Self-modifying code is
used to change the rotate instruction.

The bit patterns are first used to display the upper rows, and then the lower rows.

See commented source code for further implementation details.