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From: daveh@cbmvax.cbm.UUCP (Dave Haynie)
Newsgroups: net.micro.cbm
Subject: Re: Turning BASIC ROM into RAM...
Message-ID: <199@cbmvax.cbmvax.cbm.UUCP>
Date: Tue, 6-May-86 11:50:57 EDT
Article-I.D.: cbmvax.199
Posted: Tue May  6 11:50:57 1986
Date-Received: Thu, 8-May-86 08:13:11 EDT
References: <2167@caip.RUTGERS.EDU>
Reply-To: daveh@cbmvax.UUCP (Dave Haynie)
Organization: Commodore Technology, West Chester, PA
Lines: 19

In article <2167@caip.RUTGERS.EDU> KOCYAN@BLUE.RUTGERS.EDU writes:
>   On the Commodore 64, is it possible to turn the BASIC ROM between addresses
>$A000 and $BFFF into RAM, and yet keep the BASIC routines there so that they
>can be modified?
>   I've tried changing the data-direction-register (location $0000), but that
>didn't seem to help at all.
>   Any advise would be greatly appreciated.  Thanks in advance.

What you want to do here is to first copy the BASIC ROM into the RAM 
underneath.  You can do this by PEEKing every location, then POKEing it
right back -- any writes to the ROM location "bleed through" to RAM.
Once this is done, use the register at 1, not the data direction register,
to turn off BASIC.
-- 

Dave Haynie    {caip,inhp4,allegra,seismo}!cbmvax!daveh
               "There, beyond the bounds of your weak imagination
                Lie the noble towers of my city, bright and gold"
								-Genesis