Re: A83: Couple of Q's...

To: Olle Hedman <assembly-83@lists.ticalc.org>
Subject: Re: A83: Couple of Q's...
From: Linus Akesson <lairfight@softhome.net>
Date: Wed, 15 Jul 1998 20:21:05 +0100
Delivered-To: assembly-83-outgoing@towerguard.unix.edu.sollentuna.se
In-Reply-To: <3.0.3.32.19980715162925.007521f0@hem.passagen.se>
Reply-To: assembly-83@lists.ticalc.org

On 15-Jul-98, Olle Hedman wrote:

>At 20:38 1998-07-12 +1000, you wrote:
>>
>>Isn't the some of the I/O pins of the z80 conected up to the LCD!!!!!!!
>>So, would it be checking the LCD or the batteries throgh some other
>>circuitry..

>Yes you can control the LCD through port 10 and 11 on the z80.. (as been
>discussed on this very list..)
>And about the batteries.. My teory is, that it works like this:
>the battery-check is in hardware, and can only return "Battery OK" or
>"Battery  not OK"  on some port..  
>I guess thare is people on this list that can confirm or reject this :)

>//Olle

You can get the battery status as a boolean, it's bit 0 of port 14h (I think),
but when the system reads this bit, it first writes something to some
undocumented bits of port 4, so there might be a selectable threshold. If
there is, that would be cool, but I see no reason why it should be.

Linus

References:

Re: A83: Couple of Q's...

From: Olle Hedman <oh@hem.passagen.se>