Re: Redesigning a new PROM for //e and //c hardware

[Benoit0123 <bgilon@free.fr>]

BLuRry wrote:
> On Monday, November 5, 2012 9:28:11 AM UTC-6, Egan Ford wrote:
>> On 11/5/12 5:23 AM, Benoit0123 wrote:
>> 
>> > potential enhanced CPU within the host (either CMOS 65C02 or a
>> 
>> > 65802).
>> 
>> 
>> 
>> I am intrigued.  This is the first I have heard of a //e with a 65802 
>> 
>> (my Apple II activity has a gap from 1986-2009).  Was this a common 
>> 
>> self-upgrade?  Is it as simple as just replacing the CPU?  Hmmm... now 
>> 
>> where to find one...
>> 
>> 
>> 
>> Thanks.
> 
> Seems it is virtually identical to a 65816 minus the bank-address byte. 
> Since the 65c02 used in the //e didn't have the SC bit-operator opcodes
> (bbr and so on) dropping in a 65802 shouldn't make any difference to any
> of
> the software.  (note: Jace emulates the SC opcodes... just in case. ;-)
> 
> -B
>
Well, it depends on the software... One can determine the CPU flavour it
runs on and adapt its strategy accordingly (eg. using MVP/MVN opcode for a
65802, but revert back to a software loop on unlucky users computers).