Re: A82: Dead list, huh?

To: assembly-82@lists.ticalc.org
Subject: Re: A82: Dead list, huh?
From: "Thomas J. Hruska" <shinelight@detroit.crosswinds.net>
Date: Wed, 03 Mar 1999 00:07:17 -0500
Delivered-To: assembly-82-outgoing@towerguard.unix.edu.sollentuna.se
Delivered-To: assembly-82@lists.ticalc.org
In-Reply-To: <00be01be6526$1cf2f640$c3313d80@res.gatech.edu>
Reply-To: assembly-82@lists.ticalc.org

At 10:29 PM 3/2/99 -0500, you wrote:
>82-PORTS or the datasheet for the display controller tells you have to do it
>(or you can use the sample program in the TI83 documentation). Just remember
>to either update the contrast value in the system part of the RAM or reset
>the contrast after you are done.

However, the contrast value in RAM is different between ROM v18.0 and 16.0.
 I had a problem with Game Wizard v2.0 on 16.0 calcs until I adjusted the
value that I read from RAM.  In order to change the contrast to be correct,
do something like this:

  ld a,($29D0)
  cp $36           ; Test for ROM v16.0
  ld a,(CONTRAST)
  jr nz,ROM18
  add a,22
  jr AnyROM
ROM18:
  add a,32
AnyROM:
  or $C0
  out ($10),a

Thanks to Dines for the ROM version location :)  Mess around with the
routine to optimize it if you can.  I just threw it together from Game
Wizard's source.

        Thomas J. Hruska -- shinelight@detroit.crosswinds.net
Shining Light Productions -- "Meeting the needs of fellow programmers"
         http://www.geocities.com/SiliconValley/Heights/8504
                    http://click-on.to/shinelight

References:

Re: A82: Dead list, huh?

From: "Dines Justesen" <dines@resnet.gatech.edu>