[Coco] What about the double speed upgrade?

[jdaggett at gate.net]

On 2 Jan 2007 at 19:15, Leon Howell wrote:

> I don't know if I'll *ever* get a fast drive working, but there are several 
> ways of making the CPU even faster, and one of them is the double speed (3.568 
> mhz) upgrade on sockmaster's web site.
> 
> Are Mark's 6309's capable of 3.5-4.0 mhz? if not, where can I get one that is?
> 
*********

The HD63C09E will run speeds up to about 4MHz. It is rated at 3MHz. 

The MC68B09E is rated 2MHz but some of the later manufactured parts will run 
speeds up to 3MHz. Motorola never graded parts beyond 2MHz. 

> What about compatability? Are there programs that will have problems at this 
> speed? What about hardware compatability?
> 
*******************

The HD6309E is 100% compatible software with the MC6809E. The revesrse is 
not true due to the extra registers and increased instruction set contianed inthe 
HD6309E.

james