Re: 6809 / 6702 puzzle

From: André Fachat <afachat_at_gmx.de>
Date: Sat, 21 Apr 2012 20:14:12 +0200
Message-ID: <20120421181412.140080@gmx.net>
> My understanding therefore is that the 6702 is addressed when the address
> lines are 1110 1111 1110 00XX or $EFE0 through $EFE3. I would 
> assume that any other reads will access non-existent devices and will
> potentially return garbage (unless there are some data bus 
> terminating resistors somewhere which would provide a known default data
> bus value).
> 
> By looking at the schematics I am also led to believe that the 6702 should
> be accessible from the 6502 processor (as the 6809 and 6502 
> appear to be "next door to each other" in the schematic diagram and share
> the address and data buses). This means that you should be able 

That confirms my analysis.

http://www.6502.org/users/andre/petindex/superpet.html

André

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