[Coco] Prototype/Breakout Board

[John W. Linville]

On Mon, Mar 26, 2012 at 12:55:04PM -0600, Darren A wrote:
> On Mon, Mar 26, 2012 at 9:17 AM, John W. Linville wrote:
> >
> > Someone did a project not too long ago that had an external CPU
> > (maybe a Propeller?) driving the CoCo's video circuits and such.
> > So, It seems like the address lines need to be bidirectional if you
> > want something like that to work.
> >
> 
> Unfortunately, the 6x09's Bus Available signal is not brought out to
> the cartridge port.  With the available signals, you should only
> change direction of the address lines to input after HALT goes low and
> remains low for the number of cycles in the longest instruction (could
> be up to 44 cycles when using a 6309).
> 
> Probably not worthwhile for a general prototyping board.

Fair enough -- not that many projects need something like that.

-- 
John W. Linville		Someday the world will need a hero, and you
linville at tuxdriver.com			might be all we have.  Be ready.