Re: Ultima & Mockingboards on each of the Apples

["Great Hierophant" <great_hierophant@hotmail.com>]

One of the things I did was to compare the Apple II ROM AppleWin uses
with the one that the MESS uses.  I did a binary copy of the a2p.d0 +
a2p.d8 + a2p.e0 + a2p.e8 + a2p.f0 +a2p.f8 and did a CRC comparison to
the stripped down version of the AppleWin Apple II ROM (which is
padded.)  The CRCs are identical for each 12kbyte file.  I would
therefore conclude that if MESS really did emulate the Mockingboard,
including its IRQs, it would crash to the monitor as well.  The only
conclusion that makes any sense is that there must be another (newer?)
revision of the Apple II+ ROMs that allow an IRQ to vector to somewhere
other than the Monitor.  Perhaps the '81 Apple II+s (Rev . 7 PCBs) have
the ROM.

Apple II ROMs (Integer BASIC, Old Monitor, Sweet 16, mini-Assembler)
should be 8KB in size.