[Coco] 6809 / General CPU question

[Phill Harvey-Smith]

On 19/02/2011 12:59, Mike Rowen wrote:
> Basic theory question here. When a 6809 is powered up, does it automatically
> begin fetching instructions at a specific location? I have been looking
> through some books, but I have yet to find any document that describes the
> boot process from the CPU perspective.

First thing it does is fetches the two bytes from the reset vector at 
$FFFE and $FFFF, this contains the address to start executing from, the 
fetched word is then placed in the PC register and instruction execution 
begins from there.

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.