Have you seen this?? (Coldfire accelerator from elbox!)

[Piru]

anyway the A1200 can use a 2mb rom

It can? There's only 1MB reserved for ROM in the 24bit address map though.

[Piru]

A80000 to B7FFFF 1 MB System ROM

That's interesting. I remember Zorro II I/O space being somewhere within Axxxxxx area.

Ah... found it from the Hardware Manual:

Memory space is the standard 8 megabyte space from $00200000-$009FFFFF. The I/O address space is mapped at $00E80000-$00EFFFFF, and a new 1.5 megabyte section (previously reserved for motherboard devices) from $00A00000-$00B7FFFF.

So re-using this address for ROM could conflict with some Zorro expansions at least.