From: Joaquim Carvalho <jdc_at_x64.com>
Date: 27 Feb 2003 16:54:49 +0000

On Thu, 2003-02-27 at 15:47, Björn Stenberg wrote:
> Joaquim Carvalho wrote:
> > As to the game there are 2 options:
> > - program it in C (experienced players will not like it if it's
> > not exactly the same as the real arcade machine)
> > - write_a/use_an_open_source 6502 emulator. The 6502 was the first
> > and only real RISC I knew (other RISCs I know have a more complex
> > instruction set than most CISCs) The 6502 in Asteroids runs at
> > the astonishing speed of 1.5MHz and does most instructions in 1
> > clock cycle. The emulator should be easy and a pleasure to write.
> > Optimized C code is probably fast enough. Rom size is 2Kb so
> > on-the-fly re-compilation is also an option.
> > Would an emulator thing be acceptable in Rockbox? The (illegal)
> > ROM file shouldn't be included but could be loaded at runtime.
>
> Having a 6502 emulator would, naturally, be immensely cool. However, it would be a pity only being able to legally distribute the emulator and not the actual game. Hence I personally vote for a rewritten C version.

A rewritten version won't be legal either because Atari has patented
the game concept. A programmer can actually be held responsible for
writing and releasing a clone - I know that first hand, back in
1983 I wrote a Pengo clone for the ZX Spectrum and was unable to
release as Atari gave no permission.

As far as I know writing an emulator is legal, emulators have been
around since 1962 and no one has been arrested for doing one:
http://www.worldofspectrum.org/EmuFAQ2000/AppendixC.htm

Doing the emulator shifts the responsibility of doing something illegal
to the user who will have to download the ROM from some underground
site. Most people who want to play Asteroids on the jukebox would have
the ROM file already.

Asteroids looks simple and it wouldn't be difficult to program a game
to look like it but making it as addictive as the original Arcade
machine is not an easy task and making a clone is not a very interesting
job for most programmers (me included), writing an emulator is.
Another advantage of the emulator is that it could be made to run other
games.

>
> > Is it possible to change the DSP decoder so it mixes an analogue
> > sound stream with the decoded MP3?
>
> Unfortunately not. The inner workings of the DSP is a closely guarded trade secret of Micronas.

Has anyone tried contacting Micronas about this?

Joaquim
Received on 2003-02-27