Re: 3.5 drive on IIe question

[dempson@actrix.gen.nz (David Empson)]

David Wilson <david@uow.edu.au> wrote:

> Unfortuately I cannot test this theory as I only have the memory card and no
> //c+. I could try my //e memory expansion card on a Zip-8MHz //e. Does the
> //c+ accellerator work like a Zip chip?

Technically, the IIc+ accelerator _is_ a Zip chip.  Apple licensed the
accelerator design from Zip Technology, and the IIc+ simply has the ASIC
and cache RAM separated from the CPU instead of everything being bonded
together in one package.

There may be minor differences in the design, e.g. the method used to
access the control registers.  Apple provided a new set of firmware
entry points to control the operation of the accelerator, but didn't
document how the underlying hardware worked.

I wouldn't expect there to be any major differences such as changes in
the behaviour of the caching and system bus accesses.

-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P O Box 27-103, Wellington, New Zealand