Re: Theorizing: Would exposing the internal 65xx CPU registers be of benefit for something?

From: Justin <shadow_at_darksideresearch.com>
Date: Wed, 22 Jun 2022 09:55:18 -0500
Message-Id: <825EB93F-226F-47F7-AD9B-A6212753AEDB_at_darksideresearch.com>
I bet you can read the register contents using side channels.

> On Jun 22, 2022, at 06:44, Baltissen, GJPAA (Ruud) <ruud.baltissen_at_apg.nl> wrote:
> 
>> Would it be anything that would make hardware designs to be 'better', 'more efficient', 'faster'... in the case that the registers would be available physically?
> 
> It would help in case of debugging. When stepping through the program one can see the content of the various registers. But unless somebody comes up with an ingenious use for these extra pins, I think it is not worth the extra costs involved.
> 
> 
>> Would having them mapped into memory addresses be of benefit?
> 
> No, in contrary. Mapping them in memory means that for every read or write some address bus output registers have to be set first and that will take time. Internal registers can be handled directly by the Instruction decoder.
> 
> 
> With kind regards / Met vriendelijke groet, Ruud Baltissen
> 
> http://www.baltissen.org
> 
> 
> 
> 
> 
> 
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Received on 2022-06-22 17:00:03

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