Re: A83: Re: The LCD Display

To: assembly-83@lists.ticalc.org
Subject: Re: A83: Re: The LCD Display
From: AutismUK@aol.com
Date: Wed, 5 Apr 2000 05:27:51 EDT
Reply-To: assembly-83@lists.ticalc.org

In a message dated 05/04/00 08:40:44 GMT Daylight Time, david@acz.org writes:

> I believe that the hardware on the 85/86 updates the LCD faster 
> than the display controller on the 82/83, which reduces flicker.  
> You will notice that Galaxian looks much better on the 86 than 
> on the 83.

I think the controller on my (newish) 83 is slower than standard ; there
have been some routines which didn't work (I think the Zelda demo
had this problem).

> That said, there is one game on the 83 where the display quality surprised
> me: the Sqrxz port.  I never bothered to look at the source since I don't
> program for the 83, but my guess is that he used a double buffer, instead of
> the normal technique of writing to a memory area and then dumping it to the
> display controller.  

I don't get it (maybe I should look at the source :)) but you still, at some 
point
have to dump it to the display controller whether you double buffer it or
whatever.

> The blur problem keeps you from writing games like a grayscale side scroller
> on the 86, simply because it doesn't look very good, no matter what you do.
> I asked Shepcar why most of his games were single screen, and that's the
> reason he gave me.  

This really showed up in my Lode Runner program ; the 8 way scrolling screen 
works beautifully in an emulator, but on my TI83 it was almost invisible. I 
made it
better by basically halving the frame rate and increasing the scrolling rate, 
but
Konstantin (who did the gfx) said it looked okay on his calc, and others he'd
tried (I think).

Thanks.

Paul Robson