Re: 65802 problem clarification

[David.Empson@bbs.actrix.gen.nz]

In article <1993Jan25.190432.4984@edsi.plexus.COM> cranem@edsi.plexus.COM (Mike Crane) writes:
> I tried (twice) to put a 65802 in a Laser 128/EX that I had.  The
> machine totally refused to function with it installed, but worked fine
> with a standard 65c02 in there.  I would say that the '802 is not
> *completely* compatible based on this evidence.  I have not, however,
> seen spec sheets from WDC to either confirm or deny this.

I have.  The IIgs hardware reference includes a 65816/65802 data
sheet.  The 65802 is pin-for-pin compatible with one particular
version of the 65C02 (which is the one used in all genuine Apples).
It is possible that the Laser uses a different version of the 65C02
(different clocking options, mainly), or uses a Rockwell 65C02 (which
has several extra instructions that are incompatible with the
65802/65816).  Either of these would cause the 65802 to be
incompatible with a Laser.
-- 
David Empson

Internet: David.Empson@bbs.actrix.gen.nz    EMPSON_D@kosmos.wcc.govt.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand