Date   : Sun, 31 Oct 2004 16:45:56 +0000 (GMT)
From   : Andrew W <a.weston2@...>
Subject: Re: &D00

In <URL:news:local.misc> on Sun 31 Oct, Jonathan Graham Harston wrote:

> > I read in one book that &D00-DFF was okay for user routines but on
>  
> That book is plainly wrong. &D00 upwards holds the NMI routine,
> &0D9F-&0DEF holds the extended vector table and &0DFx holds the ROM
> workspace flags. If you trample over the NMI area, any sprurious NMI will
> crash the machine. If you trample over the extended vector area and
> vectored system call could crash the machine. If you trample over the ROM
> workspace flags ROMs will trample over undefined bits of memory.
>
I think that the book was written with Model A users in mind and perhaps
was assuming most would be using tape and be without Econet, further
ROMS etc.


A.Weston
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