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From: joels@tekred.UUCP (Joel Swank)
Newsgroups: net.micro.cbm
Subject: Re: Turning BASIC ROM into RAM...
Message-ID: <537@tekred.UUCP>
Date: Thu, 8-May-86 11:29:59 EDT
Article-I.D.: tekred.537
Posted: Thu May  8 11:29:59 1986
Date-Received: Sun, 11-May-86 15:40:46 EDT
References: <2167@caip.RUTGERS.EDU>
Organization: Tektronix, Inc., Beaverton, OR
Lines: 21

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 $0000), but that
> didn't seem to help at all.
>    Any advise would be greatly appreciated.  Thanks in advance.
> 
>                                         Rob.
> 
   First copy all of BASIC ($A000-$BFFF) to itself. This makes a copy in
the RAM underneath. Then set bit 0 of location 1 (LORAM) to zero. BASIC
is then running from the RAM. To switch back, set the bit back.
 REF: C-64 Pgmrs. Guide page 260-268.

 Joel Swank
 Tektronix, Redmond, Oregon