Re: A89: Important question

To: assembly-89@lists.ticalc.org
Subject: Re: A89: Important question
From: Johan <johei804@student.liu.se>
Date: Sun, 14 May 2000 09:04:51 +0200
In-Reply-To: <200005140620.e4E6K6w04689@neretvica.utic.net.ba>; from Zeljko Juric on Tue, May 16, 2000 at 08:22:42 +0200
References: <200005140620.e4E6K6w04689@neretvica.utic.net.ba>
Reply-To: assembly-89@lists.ticalc.org

On Tue, May 16, 2000 at 08:22:42 +0200, Zeljko Juric wrote:
> 
> I have very important question which I can't check by myself because
> I have not a graphlink.

No? Then build one! It's easy! :-)

> The question is: what happens on real 68000
> (e.g. on real TI-89) if you tried to jump to the address which is
> greater than 16 MB (note that PC register on 68000 is 24-bit long,
> so the max address is 16 MB)?

I wrote a small test program and found that ...

* The address bus is 24 bits wide, the top 8 bits of *any* address will be
  ignored.

* PC is a true 32 bit register. It remembers the top 8 bits like any address
  register.

/Johan

References:

A89: Important question

From: "Zeljko Juric" <zjuric@utic.net.ba>

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