[A86] Re: The f'n 86 screen

To: assembly-86@lists.ticalc.org
Subject: [A86] Re: The f'n 86 screen
From: rabidcow@juno.com
Date: Tue, 2 Oct 2001 00:11:46 -0700
Reply-To: assembly-86@lists.ticalc.org

On Mon, 1 Oct 2001 20:25:37 -0400 Aaron <acurti1@umbc.edu> writes:
> I had tried at one point to write a 1:1 routine, with either plane
> having a different contrast.  It worked to some extent; there should

Well, hey... I tried to use this method to improve the shades of the
standard ratios, but I guess I didn't change the contrast by a noticeable
amount.  I wish I had known that someone else had already tried it...

> For the interested, I'll try and explain what's going on.  When an
> interrupt occurrs, you have to write to port 3 and tell the hardware
> "ok, good job" by turning off whichever type of interrupt it was.
> Otherwise things get ugly...  Of course you then have to turn the
> interrupt back on if you want things to continue working.

Ah!  That makes sense, writing a zero to the bit disables the interrupt
and clears the flag.

> What I figured is that it doesn't matter if you turn off the one 
> that
> didn't occur, so it's simpler just to turn them both off and be done
> with it.  But like I said, there's no benefit other than saving a
> couple bytes...

If it's possible for one interrupt to occur while the other is being
processed, you might miss it using the fast method, but it probably
doesn't matter.

And why not save all those extra bytes if you can?

-josh
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Follow-Ups:

[A86] Re: The f'n 86 screen

From: Aaron <acurti1@umbc.edu>