This is a chip8 compiler. See octo, chip8 and octojam.

compile.py compiles the file code into CHIP8, which then gets injected into template.html, which contains a CHIP8 VM. The result is written to out.html which can be openend to see the file code running.

compile.py takes HEX encoded (in UTF-8) and outputs it into the code the CHIP8 vm expects (integers in UTF-8). That means the text 63 00 stores the number 00 into register 3 (for reference see http://mattmik.com/files/chip8/mastering/chip8.html )

Additionally compile.py has some inbuild commands or mmemotics. Currently supported:

code	meaning	CHIP8 code
set XXX	set register i to number XXX	AXXX
jump XXX	jump to code XXX	1XXX
label WORD	remember this location as WORD, see labeling below	no opcode
vY XX	set register Y to XX	6YXX
sprite vX vY Z	draw sprite (memory location i) at screen location register X register Y with height Z	FXYZ
inc XX	this has a bug, don't use it. I have no clue what it does.	??
key Y	wait for key press and write to register Y	FY0A
add Y XX	add value XX to register Y	7YXX

labeling

To make it easier to jump to code locations and to draw sprites, labels can give a (human understandable) name to a code location. label XX remembers the current code location and the name can then be used by the set and jump macros by writing @LABEL instead of a memory address. Example:

set @sprite
label mainloop
sprite v1 v2 8
add 1 v1
jump @mainloop
label sprite
[sprite here]

This first sets register i to the sprite stored after label sprite, then draws it to the screen with the coordinates v1 and v2 (sprite has height 8), then adds 1 to the register v1 and jumps back to sprite drawing.

Basically this repeatedly draws the sprite with a different x coordinate.