Re: Screen memory mapping VIC-20

From: Pasi 'A1bert' Ojala <>
Date: Fri, 7 Jul 2017 15:08:53 +0300
Message-ID: <>
On 07.07.2017 14:12, Anders Carlsson wrote:
> For a long while there was a misunderstanding about the VR/W signal on 
> the bus that it would be for video R/W but it is not, it is just a bad 
> naming convention of the signal.
As far as I remember off-hand, the VR/W is indeed the VIC-I R/W signal. 
The problem is that the cartridge port only carries the 6502 databus, 
not the part of the bus that it shares with VIC-I. I.e. during a VIC-I 
access the cartridge databus is separated from the video databus.


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Received on 2017-07-07 13:00:03

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