Re: [stella] Experimental Text Screen

Subject: Re: [stella] Experimental Text Screen
From: Adam Thornton <adam@xxxxxxx>
Date: Fri, 24 Jan 2003 21:21:33 -0600
On Sat, Jan 25, 2003 at 12:17:22PM +1100, Andrew Davie wrote:
> The depth my system can do is actually only a function of available RAM...
> it takes 12 bytes per text line.  If you have a single line at a time, then
> you need to reload those 12 bytes with appropriate pointers for the next
> line - and reposition the sprites, etc., which gives about (say) 5 scanlines
> inbetween each text line.  You can, however, pre-load multiple lines (the
> current sprite system does 6 lines) for a total of 6*12 = 70 bytes of RAM.
> So you could do your text as two groups of 6-lines each, but with a much
> larger gap between them, as you need to recalculate 70 bytes between -
> probably 20 scanlines or so.
> Currently each text line is 16 scanlines deep.  This is adjustable.  Assume
> 8 is all that is needed, and that we can redo the RAM pointer loads in 5
> scanlines, then that's 13 scanlines/row... so I don't see any major obstacle
> to having a 20-line display.

Well, except the RAM usage.  I need to go through ScottFree and see how
little I can get away with for one of the early ones, say, Adventureland
or Pirate Island.

You need a Location line/status bar at the top, for which I think a
single line should suffice, and a command prompt (another single line)
at the bottom.

You could probably make do with an 18x6 or smaller region in the
middle, as long as you had a <more> sort of prompt.

Archives (includes files) at
Unsub & more at

Current Thread