Re: 6809 mill clone

[Alex Freed <alex_news@alexfreed.com>]

On 7/26/2012 6:39 PM, Antoine Vignau wrote:
> They may contain the same disks but I see two entries from where I stand :-)
>
> http://www.brutaldeluxe.fr/public/mill6809.zip
>
> http://www.brutaldeluxe.fr/public/os9.zip
>
> Antoine
Great! There are a lot of images there that I didn't find before. That's 
the good news. The bad news is that I took a quick look at all the 
images that are supposed to boot OS9 and they all have the same bytes at 
the 0x14FE, 0x14FF.
 From the boot sector disassembly (and actual observations) it is clear 
that 4 sectors worth of 6502 code is loaded from $C00 to $FFF. And 48 
sectors of 6809 code starting at $9000 right up to the end of the 48K. 
The last 2 bytes at $FFE-FFF are the reset vector for the 6809 assuming 
my information about the memory remapping is correct. It comes from here:
http://www.hackzapple.com/ORG1/M2/COPROC/6809MILL.HTM

----------
Sans cette carte fille, la carte Stellation Mill a deux cartographies 
d'adresses : la premi�re identique � celle du 6502, la seconde inverse A15.

La cartographie OS/9 est la suivante :
	6809    6502
	0xxx    1xxx
	...     ...
	Axxx    Bxxx
	Bxxx    Dxxx    L/C
	Cxxx    Exxx    L/C
	Dxxx    Fxxx    L/C
	Exxx    Cxxx    I/O space
	Fxxx    0xxx    ZP+stack+text
-------------

This sure makes sense. Is there code that patches those memory locations 
at run time?

-Alex.