[Coco] Prototype/Breakout Board

[John W. Linville]

On Mon, Mar 26, 2012 at 06:58:05PM +0100, Phill Harvey-Smith wrote:
> On 26/03/2012 16:17, John W. Linville wrote:
> >On Sat, Mar 24, 2012 at 11:32:35PM -0400, jdaggett at gate.net wrote:
> >>Unidirectional Ouput from the Coco buss and microprocessor
> >
> >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.
> 
> But to do this would you not need to be able to tri-state the bus ?
> Unless you could just assert HALT and then drive the bus externally.

http://www.coco3.com/community/2011/06/prococo-cart-a-propeller-based-tandyradio-shack-color-computer-2-cartridge/

He asserted HALT and took over the system with the Propeller.

> Though admittedly that would not be the normal way to use the bus.
> 
> BTW why do people seem to spell bus as buss, is this a US / UK
> English thing ? I perticually notice it on this list which has a
> large number of members in the US.

Beats me -- FWIW, ISTRC seeing the "buss" spelling on a number of
80's era schematics for computers and arcade machines.

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