Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!hp-pcd!hpvcfs1!johne
From: johne@hpvcfs1.HP.COM (John Eaton)
Newsgroups: comp.misc
Subject: Re: Help Hapless Hardware Hacker
Message-ID: <960001@hpvcfs1.HP.COM>
Date: 17 Aug 90 19:20:40 GMT
References: <2930@sodium.ATT.COM>
Organization: Hewlett Packard, Vancouver, WA
Lines: 13

<<<
< Your address decoder should decode A0 - A9, AEN*, and IOR*/IOW*.
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The classic symptom of ignoring AEN* is that DMA devices will not
work when the board is inserted. DMA opertation will strobe both
IOR and MEMW at the same time it places a valid memory address on 
the BUSS. If that Memory address is the same as your IO address
then AEN* is the only signal that prevents your card from blasting
the DATA Byte. If you ignore it then it won't work.


John Eaton
!hpvcfs1!johne