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From: loki@moncam.co.uk (Never Kid A Kidder)
Newsgroups: comp.sys.atari.st
Subject: AES/VDI - Help!!! I'm confused!!!
Message-ID: 
Date: 26 Sep 89 11:19:43 GMT
Sender: loki@moncam.co.uk
Distribution: comp
Organization: (n) The process of becoming an organ.
Lines: 36

I've read as many different definitions of AES/VDI as I have documents
on these chaps, and my head is in danger of falling off.  I've looked
at the Sozobon library sources, and it would appear that AES calls are
made with a trap #2, with the AES opcode in d0 and some kind of
parameter in d1.  However, my VDI manual says you need to set up a
parameter block consisting of pointers to a control array, an input
parameter array, an input point coordinate array, an output parameter
array and an output point coordinate array, with the opcode in the
first byte of the control array, and bung that into d0 - nothing about
d1 mentioned here - and then do a trap #2.

I have a complete, if obscure, description of VDI, but NOTHING on AES
apart from the code in crystal.s in the Sozobon library, which gives a
list of function numbers, but not what they do.  I therefore have no
idea how to call AES.

Sooo... 

(1) do I have AES or VDI? I'm running a very early TOS.

(2) do AES and VDI differ in the ways I have described above, or have
I misread something?

(3) Can anyone give me a help file, or even a source listing for AES,
so that I can actually use it?

(4) Books? Will Abacus' ``GEM Programmer's Ref'' help me out with AES?

Thanks in advance to anyone that can help.
--
   Harry Fearnhamm,         EMAIL: harry@moncam.co.uk
    Monotype ADG,                  ...!ukc!acorn!moncam!harry
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