Re: 65C816 adapter for 6502 computers (aka Apple II)

["Bryan Parkoff" <bryan.nospam.parkoff@nospam.com>]

Vince,

    You win!!  I am curious.  Do you own "Understanding an Apple II+ & Apple
//e" manuals?  Please tell me how did you make 65C02 and 65816 CPU to work
with Apple II+?  Did you plug 65816 CPU into Apple II+'s motherboard
already?  The problem is that Apple II+'s ROM must be located in Bank $FF
because it is where $FFFC is pointing in Bank $FF.

-- 
Bryan Parkoff
"Vince Briel" <vbrielnospamme@comcast.net> wrote in message
news:HxO3c.1120$mM.32058@attbi_s02...
> "Bryan Parkoff" <bryan.nospam.parkoff@nospam.com> wrote in message
> news:eZN3c.19007$u53.1941@fe1.texas.rr.com...
> > Ouch!!
> >     I am sorry to state.  Unfortunately, 65816 CPU will NOT WORK on
Apple
> > II+ nor Apple //e because 65816 CPU's and 6502 CPU's timing are not
EXACT
> > the same.  They have different nanosecond measurement.  For example,
6502
> > CPU requires 400 ns to run while 65816 CPU runs 250 ns (I can't remember
> > exactly.)
>
> This circuit takes care of the times and the bus contention problems.
>
> >     "Understanding an Apple //e" manual stated that someone tried to
plug
> > 65C02 CPU into Apple II+, but very several instructions work while often
> it
> > crashes at all times.
>
> I've swapped them no problems.
>
> Vince
>
>
>
> --
> Replica I
> The Apple I clone
>
> http://www.applefritter.com/apple1/members/replica1/index.htm
>
>