Re: A86: Re: LCD stuff

To: assembly-86@lists.ticalc.org
Subject: Re: A86: Re: LCD stuff
From: TGaArdvark@aol.com
Date: Fri, 19 Nov 1999 01:34:29 EST
Reply-To: assembly-86@lists.ticalc.org


> By the way, how much power does the processor consume when the calc is
> 'off'?  I looked up the halt instruction in the z80 data book to try and
> resolve an old dispute with a friend of mine over whether it is ever
> truly off or not (off as in no power usage).  I found that the halt
> instruction waits for an interrupt, during which time it runs a
> continual cycle of NOP instructions internally, to maintain memory
> refresh logic for dynamic memory chips.  I don't think the 86 uses
> dynamic memory (or maybe it does?), but the z80 still runs during a
> halt, so therefore it must consume power, so therefore the calculator is
> never truly turned off except when the batteries have been removed.  How
> much power does it take?  If you left it off for a long time, would your
> batts run down?

This was documented on ticalc.org when it first opened.  It's
probably still there, hidden in some directory.  The TI-85
consumes 8 microamps or something like that when off.
It will theoretically drain your AAA batteries in 350 years.

Follow-Ups:

Re: A86: Re: LCD stuff

From: Cassady Roop <croop@oregontrail.net>