CUBIX/6809 updates

[woodelf]

Roger Merchberger wrote:

>
> Firstly, I'd like to mention that I've always wanted to build my own 
> homebrew 6809 system... altho I've been thinking of designing my own 
> buss system (around 80 pins or so) so other CPUs could be used if 
> desired. I was thinking of a multi-board system with a 6-7 socket 
> backplane. I want it to be educational to others (read: see-thru 
> Lucite case & lotsa Blinkenlights! ;-) at the same time that I learn 
> from it, too.
>
The XT connectors can be got cheap. For a 8 bit CPU how many pins do you 
really need?
Only I/O need go on the backplane - 32k x 8 ram is dirt cheap and too 
fast for a 2 MHZ 6809.
Now a 4 MHZ 6809 ( that are not made ) would be just about right.

> For a few reasons, S100 is not an option: I want the system smaller / 
> easily portable (I'm guesstimating in inches: 6x6x9, with an external 
> 5V only switcher), and I also want it to be easily buildable by a 
> hobbyist. Trying to dremel an S100 cardedge would seem to be quite a 
> bit of work for not a lot of gain - but square boards with a pair of 
> 40-pin IDE connector (for example) edge-soldered on would be pretty 
> easy to do at home.
>
I think protype PCB's are still better as when you add up the price for 
WireWrap sockets
I think works out the same ballpark figure. I think the time doing a 
PCB  is longer but
less hassle since mistakes in wire wrapping are very hard to find.

> I do have a question:
>
> Are there any 80-100 pin buss structures already in use I could copy 
> that might fit my bill? I'd rather do something that might be 
> compatible with something else out there if it's similar enough to 
> what I want to accomplish.
>
> I'm hoping to take lots of pictures & basically make the design free 
> on the web as I do this, mainly to show people if an idiot like me can 
> make a computer, so can you! ;-)
>
That is my line.

> Oh, and for the record: Cubix looks *kewl*. ;-)
>
>
> Them's fightin' words. 64K w/OS-9 got me thru High school & my first 
> year of college, before I got my CoCo3 & 128K (later to 512K) but I 
> still had a maximum 64K code space - and that kept me working until 
> the mid-90's. Other than running (crawling) Autocad, my '386 was the 
> 'toy' and my CoCo was the workhorse. Once I got an EISA 486-66 server 
> from my (then current) employer, did I consider the CoCo my secondary 
> machine.
>
The crappy hardware on the COCO keeps it a toy.

>
> A few of those microcontrollers have 128K of flash on 'em now.
>
> I want my CoCo on a chip! ;-)
>
I want a Gimix!  ( I think that is how it was spelled )

> Laterz,
> Roger "Merch" Merchberger

Just where are you that it is 30 below?