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Path: utzoo!linus!philabs!cmcl2!harvard!uwvax!astroatc!nicmad!brown
From: brown@nicmad.UUCP
Newsgroups: net.micro.cbm
Subject: Re: Turning BASIC ROM into RAM...
Message-ID: <684@nicmad.UUCP>
Date: Wed, 7-May-86 00:45:43 EDT
Article-I.D.: nicmad.684
Posted: Wed May  7 00:45:43 1986
Date-Received: Sat, 10-May-86 13:09:33 EDT
References: <2167@caip.RUTGERS.EDU>
Reply-To: brown@nicmad.UUCP (Mr. Video)
Organization: Nicolet Instrument Corp. Madison WI
Lines: 23

In article <2167@caip.RUTGERS.EDU> KOCYAN@BLUE.RUTGERS.EDU writes:
>From: KOCYAN@BLUE.RUTGERS.EDU
>   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.

Basically you PEEK all of the addresses and then POKE them back to the same
addresses.  In the C64, when you POKE ROM, it is placed into RAM.  Then you
can set the register bits to turn off BASIC.  Check the 'Programmer's Reference
Guide' for correct bit changing.

The net result is that you are now running BASIC out of RAM, allowing you to
change things.
-- 

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