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From: toddpw@tybalt.caltech.edu (Todd P. Whitesel)
Newsgroups: comp.sys.apple2
Subject: Re: PUSHing to bank $E1
Message-ID: <1990Aug23.210551.6150@laguna.ccsf.caltech.edu>
Date: 23 Aug 90 21:05:51 GMT
References: <4058@crash.cts.com>
Sender: news@laguna.ccsf.caltech.edu
Organization: California Institute of Technology
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mquinn@pro-gsplus.cts.com (Michael Quinn) writes:

>I've heard people talking about pushing to SHR Ram (bank $E1).  How is this
>possible?  I thought you could ONLY have a stack in bank $00... even with
>shadowing, this would only go to bank $E0, not $E1.  Is there something I've
>missed?

Yes -- auxiliary memory. You can flip a switch to make bank $00 writes (or
reads, you can control them seperately) go to bank $01.

Add shadowing of the SHR buffer in bank $01 and you get stack/dp writes going
to $01 and $E1.

Todd Whitesel
toddpw @ tybalt.caltech.edu