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Date   : Sat, 11 Jun 2011 21:34:54 +0100
From   : afra@... (Phill Harvey-Smith)
Subject: Atom banked dos rom.

Hi all,

I'm currently doing some changes to the Atom driver in MESS, and have 
come across something I need clarification on.

The current driver has spaces for 16 4K roms banked in at #A000-#AFFF, 
which which are selected by writing the bank number to #BFFF, this is 
also supported by my RAM-ROM board.

However the driver is also coded with two #E000-#EFFF roms (as well as 
automatically using the DOS rom) though there is no code to page this 
rom in or out. Was there ever any hardware that allowed this, and if so 
how widely was it available ?

I'm also tempted to remove the DOS rom auto load from the driver as the 
DOS was an addon board, and should always be optional, and there is 
currently no way of disabling it.

Cheers.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.
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