[Coco] What about the double speed upgrade?

[L. Curtis Boyle]

On Thu, 04 Jan 2007 22:49:25 -0600, John Kowalski <sock at axess.com> wrote:


> At 06:04 PM 04/01/2007 -0600, L. Curtis Boyle wrote:

>>     Sock's (and Bob Puppo's before him) clock doublers only double the

>> speed when the CPU is not accessing RAM. So, you are right, in 6309  

>> native

>> mode, where the chip caches the instruction byte, you don't see as much  

>> of

>> a gain (except on many cycle CPU instructions that don't touch RAM, like

>> DIVx and MULD instructions). On things like TFM, it won't speed up at  

>> all.

>

> Bob Puppo designed one too?  There was *yet another* guy who was trying  

> to

> do something similar at the time that I was doing mine too.  His

> idea/approach was very different from mine, so the performance would have

> been very different.  I don't know if he actually did build it, though.

>

> Does anyone know how Bob's design would have worked and how much it  

> affected

> CPU performance?  Was it sold?

>

>                                          John Kowalski (Sock Master)

>                                          http://www.axess.com/twilight/sock/

>

>

    It was originally done on a Coco 3 around 1989, I think. It was part of  
the original design of the TC-9 (later ditched because it require too much  
tweaking on each manufactured board).


-- 
L. Curtis Boyle