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Path: utzoo!watmath!clyde!burl!ulysses!bellcore!decvax!decwrl!muscat!striepe
From: striepe@muscat.UUCP (Harald Striepe)
Newsgroups: net.micro.atari
Subject: Re: ACTION! and DOS XL
Message-ID: <115@muscat.UUCP>
Date: Thu, 16-Jan-86 18:09:49 EST
Article-I.D.: muscat.115
Posted: Thu Jan 16 18:09:49 1986
Date-Received: Sat, 18-Jan-86 07:46:26 EST
References: <860115113348.02k@CITHex>
Organization: DEC Western Region Operations, Santa Clara, CA
Lines: 38

> 
> On the subject of bank switching in the supercartridges, does anyone
> know the software proceedure for getting the cartridge to swap?
> Perhaps writing to a particular address in the cartridge address
> space?  

The "SuperCartridges" make use of the CARTSEL (?) line at $D500.

Typically,  the lower 4K of cart space are switched ($A000-$AFFF).

Location $AFFF contains the current bank number (I think....).

To switch,  simply load the bank number in X,  and store the accumulator
at $D500 X indexed.

Bank 8 switches out the complete cart to make RAM available (all 8K).
Selecting any valid bank restores the cart.

e.g.:	select bank 0

	LDX #0
	STA $D500,X

	select RAM

	LDX #8
	STA $D500,X
Dont't forget to worry about the display location and OS database when
making the cart appear and disappear....



-- 
Harald Striepe
DEC APB-WEST
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