Re: [stella] Re: Lode Runner

Subject: Re: [stella] Re: Lode Runner
From: "Eric Ball" <ericball@xxxxxxxxxxxx>
Date: Thu, 1 Apr 2004 21:03:57 -0500
> BTW, if you are having trouble with your kernel you really should fully
> exploit the SC RAM.  I read through your journal about how you were doing
> some self-modifying code and I think that's the key to doing this game
> right without lots of flicker.
> You can basically copy the kernel code to RAM (or have a bunch of
> kernel modes and overwrite JMP addresses to script out which to run and
> when) on the fly between frames.  Assuming there is enough CPU time
> inbetween frames, that would allow for as much flexibility as you can do
> a static title screen since nothing really has to be evaluated inside the
> kernel anymore.

I hadn't planned on going as far as using SC-RAM for code changes.  (The
self-modifying code was interesting, but then I figured out a way to do the
same thing without the SMC.)

But I am using SC-RAM heavily, sorta like you would on the 5200.  Four pages
of RAM are used to generate the playfield background (which includes the
gold & dirt), and two pages of RAM are used to store the player graphics.
This should make the kernel fairly simple.

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