[Coco] [COCO] Stacking the 6309?

[Dave Philipsen]

I think Bruce was asking why one would bother to have a switchable 
6809/6309.  Since the 6309 acts just like the 6809 in emulation mode, 
why not just install a 6309 and be done with it?  One reason was given 
that a person might want to have that ability if he were specifically 
writing programs that would work with either CPU but would optimize if 
the 6309 were installed.  You could switch back to the 6809 to be sure 
that your program would work correctly on it.

Dave


On 3/31/2017 10:57 AM, Salvador Garcia via Coco wrote:
> There is software that takes advantage of the 6309's enhanced features that are not available in the 6809. Additionally, some (all?) of the 6309's instructions are optimized, so they run a tad bit faster than in the 6809. If for no other reason, the 6309 can provide a slight speed boost. I've read here that a 10% increase in speed is realistic. Salvador
>
>
>        From: Bruce W. Calkins <brucewcalkins at charter.net>
>   To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
>   Sent: Thursday, March 30, 2017 8:52 PM
>   Subject: Re: [Coco] [COCO] Stacking the 6309?
>     
> Since the 6309 normally works like a 6809, why bother?
>
> Bruce W.
>
>
>
> On 03/30/2017 05:59 PM, S Klammer wrote:
>> A while back, we had some discussion about using a ZIF type socket to allow
>> swapping back to a straight 6809.
>>
>> Seems Chris Burke (of Burke & Burke) provided some instruction on just
>> stacking the 6309 on top of the existing 6809, along with a switch...
>>
>> http://www.6809.org.uk/dragon/6309fit.shtml
>>
>> Shain
>>
>