16 bit 6502?! No, you don't want it... trust me!

From: Andrew Davie <adavie_at_mad.scientist.com>
Date: Sat Feb 28 18:11:56 1998

>mmm, a //gs... yes please here also. the thought of a 16-bit 6502 to
>play with... :> (yep, even though we have a special affection for the
>much maligned 286.)

Having spent 2 years programming the 65816, believe me you DON'T want to
play with a 16 bit 6502!!!! The memories, the memories.... There was a
processor dog if ever I saw one. Interpretation of opcodes was dependant on
the mode the processor was set to, and so if you branched to a section of
code when you were in the wrong mode, results were... screwy.

All sorts of wierd and wonderful things when you switched modes; for
example switching from 16 bit accumulator to 8 bit cleared the high byte,
but switching the index registers the same.... didn't.

It was a very painful time in my life :)

Received on Sat Feb 28 1998 - 18:11:56 GMT

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