Re: Microsoft Premium Softcard //e doesn't fit in my Apple //e!

[Michael J. Mahon <mjmahon@aol.com>]

Steven Hirsch <snhirsch@gmail.com> wrote:
> On 02/20/2013 09:47 AM, gids.rs@sasktel.net wrote:
>> 
>>>>    I have one of my Freed clones running at 20Mhz :-).
>> 
>>> Yeah, Steve.  I recall that Jim Lill posted some instructions on the old
>>> GEnie site for getting the card to run at 9 mHz.  I followed them, and it
>>> ran at 9 mHz without a hitch.  (Probably still does.  I should be able to
>>> check that out in a couple of months after I resuscitate some other
>>> things.)  In addition to the crystal change, the card had to be
>>> repopulated with the F version of the several chips.
>> 
>> 
>> Has anyone ever tried upgrading a Z80+  with its far fewer chips?
>> 
>> http://apple2info.net/index.php?title=Z-80_Plus
> 
> Unfortunately, the architecture of the traditional Softcard (of which the
> Z80+ is a knockoff) dictates the CPU clock (which is derived from the
> motherboard rather than an on-board oscillator).  Not much to be done about it.

I remember its clever "syncopated" clock even got a write up in EDN at the
time. 

-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon