Ideas for a simple, but somewhat extendable computer bus

[Veit, Holger]

Am 19.11.2017 um 16:08 schrieb emanuel stiebler via cctalk:
> On 2017-11-18 23:48, Jim Brain wrote:
>
> > Looking at the schematic for the ECB, I cannot find any description of
> > the signals BAI, BAO, IEI, and IEO.  Can anyone shed some light on the
> > function of these signals?
>
> Here again:
>
> https://en.wikipedia.org/wiki/Europe_Card_Bus
>
> I have some ECB documentation "somewhere", but I'm moving so it is in 
> one of the 100s boxes somewhere :(
>
> But the guys on the retrobrewcomputers can help you for sure.
>
> And yes, I like ECB, it was small & simple, you still can get boards 
> for it, and the DIN conectors I still use ...

ECB is, like many similar approaches, basically Intel world, i.e. 8085, 
8088, Z80 (ok, that's Zilog). It is rather tricky
to adapt to the 6xxx (6502/68xx) world; and given the former Kontron et 
al socienty, it was basically used for a Z80 line
of CPU and peripheral boards, not much else.

To add another idea, why not run the IBM-XT bus on the DIN41612 
connector? This is to avoid the card edge connectors.
Use A+C with the classic 62 pins of the XT connector (2 are unused), and 
add the B pins in case to extend to the AT bus.
While the XT bus is also Intel world, it has been already successfully 
used for 68xx (6809) multiprocessing. Read
http://www.bradrodriguez.com/papers/ (section "Multiprocessing for the 
Impoverished...").

-- 
Holger