Re: Not your father's Applicard

[MdntTrain <js@cimmeri.com>]

> I'm always up for a challenge, so why not?  The first order of business is to
> find some architectural information on the 6809 Mill.  The second is to
> reverse engineer the little piggy-back board that made it possible to run OS-9
> on the Apple.  If the implementation is anything like the CoCo (a good bet),
> memory re-mapping is a requirement.  Everything in OS-9 is fully relocatable
> and it dynamically maps logical <---> physical address space in 4k chunks.  My
> CoCo has 512K installed and it's able to use all of that by swapping these
> chunks into the 64k address space as needed by the currently running task.
> Task switching is triggered by a hardware timer interrupt.  Quite
> sophisticated for a little machine.
>
> The 6809 architecture is not really very similar to the 6502, and is highly
> optimized for relocatable, PC-relative addressing.

Hehe.. well, likely the first is to wait for Alex to be on board with
all this.. as without his projects, it's a no-go.

Is the Mill similar to the PCPI card in that it's a full computer
running with the Apple II as a terminal host?    What would the Mill
have been typically purchased for?

I have a .pdf of info on it, and I'll try to scan an original Mill ad.

 JS