On 09/18/2012 05:22 PM, Spiro Trikaliotis wrote: > Helo Segher, > > * On Tue, Sep 18, 2012 at 12:44:48AM +0200 Segher Boessenkool wrote: > >>> Thus, the data bus is not really tristate. >> >> A MOS input does not sink any significant current. > > A good point that I totally overlooked. Yes, with MOS, this setup should > be (almost?) equivalent to tristate. But academically, it still isn't. ;) Problem is, you can't really tristate an input. No matter what, you will always have the input stage visible as a load. Holds true with TTL too. But the real question is, what signals of the 6510 are controlled by AEC? The 'A' stands for 'address', but does it also control other signals including the data bus? From the 'scope readings I'd say it also controls R/_W, but can't really say anything about the data lines. Gerrit Message was sent through the cbm-hackers mailing listReceived on 2012-09-18 17:00:35
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