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Re: CFFA for IIc and IIc+?

sfahey wrote:

  To: Michael J. Mahon
  Re: Re: CFFA for IIc and IIc+?
  By: Michael J. Mahon to comp.sys.apple2 on Thu Apr 09 2009 12:39 am

 > Actually, I'd abandon the "Slinky" interface entirely and use a RAMWorks
 > interface.  The bank-switched model is more useful, since it can be
 > directly addressed instead of read through a register.  You can run code
 > from an AUX bank, for example.
> > Once you have access to the address bus, you can easily implement the 
 > RAMWorks interface, without any impact on slot addresses at all.
> > That frees up slot 4 for a flash disk. The ROM code could be modified 
 > to boot from slot 4 either by default or if the built-in disk is not
 > ready.  Perhaps the firmware could check an Apple key to boot from
 > the floppy, normally defaulting to the flash drive.

I second this approach. Do you think there are any softwares out there that
check machine ID that might break or fail to be compatible with that
arrangement?


There was very little IIc-specific software.  And support for memory
expansion is pretty independent of the machine type, as long as a
standard architecture is used.  I've never seen software that supported
memory expansion that did not support the RAMWorks interface.

That interface involved a single I/O address (slot 0 associated, IIRC)
that was used to set the bank register.  All other controls were the
standard AUXRAM controls.

-michael

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