Diamond for MS-DOS in 8086 assembly
Author: dmsc
Category: Christmas Challenge
System: IBM PC and Compatibles
Language: Assembler
Len source code: 144
Len exe file: 32
Len code only: 32
Instructions:
You can run the DIAMOND.COM executable in a DOS windows, remember to type CLS
first to clear the screen.
The included floppy disk image boots to MS-DOS 3.3, type DIAMOND at the DOS
prompt to run the program.
Note that this program does not terminate, and can take a few seconds to draw
the complete pattern.
Description:
This program calculates the position of the stars to draw using two different
formulas:
X = (N - 1) % 18
Y = (N + 1) % 24
And:
X = 18 - (N - 1) % 18
Y = (N + 1) % 24
The first formula produces the descending diagonal lines, and the second
formula produces the ascending diagonals.
Only the points with Y >= 5 are plotted, this leaves 4 blank lines at the
top of the screen.
To assemble the program, use NASM, or AS86 or other similar assembler.
Comments:
I included two source files, a commented one and a minimized source that is
only 144 bytes of size.
