[Coco] COCO3 CPU

[Arthur Flexser]

There is an undocumented opcode, $3E, that does a reset on a 6809 but is
unsupported on the 6309 and will probably crash the machine, since it is
vectored to an "illegal opcode" location in low memory that contains garbage.  
So, just poke $3E into, say, $3000, do an EXEC &H3000, and see whether the
computer does a reset (6809) or some unpredictable thing (6309).

Art

On Thu, 24 Apr 2008, John T Chasteen wrote:

> I HAVE OPENED MY SPARE COCO3 WITH THE 612 MEMORY BOARD
> 
> Is there any peek or poke that I can use to determine which CPU is
> installed.
> 
> I think the chip I can see is the Video chip. I hate to unplug the
> printed circuit
> 
> memory board.  I have the Super IDE unit and I understand the CF unit is
> either
> 
> programmed for a 6309 or 6809. Mark told me one of the CF units could be
> with either
> 
> and one can only be used with one CPU. I don't know which is limited.
> Mark what
> 
> did you tell me.
> 
> John 
> 
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