512-byte OS Contest

[Troy Martin]

Here's zeroflag's entry, a limited basic-like interactive interpretive language!

@inflater: I never got an email from you

[Dex]

I will wait a day or two, than i will take screenshots of the entrys and post a link.

[Troy Martin]

My entry, |)emOS is complete, it's not much, just a little shell with 1-letter commands in 512-bytes with a register dump tool for fun

Commands: e (echo), d (dump), h (random number generator), ? (help).

[Troy Martin]

Zenith's entry, a snake game, is here!

[geppy]

Every single person here tries to put in one single feature.Could you explain how come is it an Operating System and whats the point of slow running Snake game without any features or effects (comparing to SSE version in Protected Mode).

[Troy Martin]

Cause it's fun.

01000101's entry is ready, a "half-baked Fallout 3 terminal interface clone!"

[inflater]

//EDIT:

Attention, please close your bids. 0:00 hours remaining

Deadline! Now it's time to check. Who's up for testing?
I'll do in case something doesn't work on my rHW.

[eddyb]

Tested Fallout3.
i used 'qemu kernel.img' from the dir where i unzipped.
the password is 'hackit' .
well, pretty, but i don't understand what he does

EDIT:
Tested Snake512.
command: 'qemu Snake512.bin'
verry funny snake game, congratz!

[Troy Martin]

Sorry for the delay but we're having serious poll issues (options doubling, some disappearing) and we need to find someone who can host a poll for us.

[inflater]

Mine results:

|)emos: compiling error,

Code: Select all

D:\OSdev\512BYTE>nasm -o boot.bin demos.asm
demos.asm:50: error: short jump is out of range
demos.asm:55: error: short jump is out of range

This can be fixed by either moving the labels onto the beginning of the file and JMP START, or just using the NEAR suffix (and setting CPU mode to 386).

Please explain, how it's useful to have section .bss, private variables and labels, and the "jmp short" suffix, Troy? These jumps are always "short", unless a memory location - another segment - is specified. Plus, these private labels and variables - that's overkill.

After all, it works.

[chezzestix]

Sorry for the delay but we're having serious poll issues (options doubling, some disappearing) and we need to find someone who can host a poll for us.

Not sure what you need but if you have the page and all you need is space on a webserver then I can help you out there.

I extensively tested Snake512. Got up to a score of 94 at one point.

Downfall:
You are allowed to turn back on yourself. This also counts as biting yourself and it gets kinda annoying when either you simply accidentally press back or the game misses your request to turn and then picks up the backward movement.

Not a bad game otherwise.

[01000101]

Tested Fallout3.
i used 'qemu kernel.img' from the dir where i unzipped.
the password is 'hackit' .
well, pretty, but i don't understand what he does

haha yeah, I forgot to give the password, but it's pretty obvious if you check out the source.

I apologize for my half-baked entry as I stopped working on it a few days ago due to some new things with my own OS.

The point is just to look similar to that of the Fallout 3 terminals, nothing more, nothing less. I originally wanted to do some 64-bit stuff, but I couldn't find any 'features' that would be worth it and could still fit in the remaining space after paging/double-sized gdt/ and just the rest of the init code. Maybe next time I'll think a little harder about things to do in 64-bit.

[mrnoob]

ah well, i got caught up in other things and couldnt do my entry in time. I was going to make an interactive debugger, from lack of ideas.

[Troy Martin]

Please explain, how it's useful to have section .bss, private variables and labels, and the "jmp short" suffix, Troy? These jumps are always "short", unless a memory location - another segment - is specified. Plus, these private labels and variables - that's overkill.

TLDR version: It's my coding style and asm optimizations.

Long(er) version:
section .bss: I use this to reserve space in memory and not have huge buffers of zeroes in my kernel, allowing more code in.
private variables and labels: I assume you mean labels starting with a dot. This is so I can use more... uniform and recognizable names in my source and not things like "word_0x_18", instead using ".temp" and ".random", etc.
short jump out of range: Sorry, I was trying to do some optimizations by using short jumps, I seem to have left a few in...

[cippo]

Oops, was I too late? Guess I misunderstood your "Entries must be in by Jan. 6th, 2009 at midnight PST (GMT-8)". Thought you meant Jan 6. 23:59:59+ 1 sec. Ohwell, I'll just dump it here anyway. It's a vi-like editor and a brainfuck interpreter. It supports moving around with h, j, k and l, opening lines above and below with O and o and inserting text with i. To interpret the file you've written press I (that is capital i). All the commands above should be inserted in command mode (you see which mode you're in in the lower left corner, C = command, I = input). And as always esc takes you back from input to command.

Cheers,
Cippo