Re: C64 / memory locations 0000 and 0001

From: Marko Mäkelä <msmakela_at_gmail.com>
Date: Thu, 31 May 2012 10:40:13 +0300
Message-ID: <20120531074013.GB3222@x220>
On Thu, May 31, 2012 at 09:33:50AM +0200, Michał Pleban wrote:
>I have been looking for a while for a solution to this problem. The RAM 
>locations 0000 and 0001 are inaccessible to the CPU, but can be read 
>using sprite collision logic in the VIC. But is there a way to actually 
>write to these RAM locations?

On certain "de00 safe" computers, there is, IIRC. When you write to 
these locations, the data lines won't be driven, but the address lines 
and R/-W line will. As a result, the RAM locations should receive the 
data that was fetched by the VIC-II on the previous cycle.

On the C128, you can cheat with by mapping the stack page to the zero 
page with the MMU, and by writing to $100 and $101.

	Marko

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