Re: Re : Re: LF: lots of stuff, mem expander

To: list-fargo@lists.ticalc.org
Subject: Re: Re : Re: LF: lots of stuff, mem expander
From: Andrew Von Dollen <warn@mail.geocities.com>
Date: Mon, 07 Jul 1997 16:28:10 -0700
In-Reply-To: <970707161815_1141796856@emout13.mail.aol.com>
Reply-To: list-fargo@lists.ticalc.org

At 04:18 PM 7/7/97 -0400, you wrote:
>So: something else: i am working on a doomlike engine... ( rather wolflike...
>). I have been coding for 2 days now and i know there is something i will
>come on: it would be much better for display if i could control when i am
>writing to video mem. 
>I mean that i would like to interleave the writing to video mem with the
>refreshing of the screen : i need to know exactly when the 92 is refreshing
>the screen... 

Ports.txt has information about when the LCD is refreshed. Look at the
description for the port at 600016.

>On the same topic, is there a way to modify the pointer to video mem ? 
>To understand this, i have been through the fargray lib ( i imagine they need
>such things as mine to do 2 plane graphics... ) : i think they replace the
>int 1 with a self made one. But what does this new int 1 do ? 

This is also possible through the use of another port. 600010 contains the
"Address of LCD memory divided by 8"   Graylib replaces Auto-Int 1 with an
interrupt that uses this port to quickly change the picture displayed on
the screen at regular intervals. Fargray simply uses graylib to put
pictures on the screen, but I think you were talking about graylib in the
first place anyways =)

>BTW, can i do this: "and   D2,D4" ? if not,  do you know a way to do this
>better than storing D2 in a program variable (  "x"  ) and doing this: " and
>(x),D4

I do believe you can, but experimentation will tell. :)

	-Andrew

References:

Re : Re: LF: lots of stuff, mem expander

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