doug@oakhill.UUCP (Doug MacGregor) (08/13/84)
I am sorry if I wasn't clear in my initial message about the
behaviour of the 68000. When I said that the 68000 does not
lose the upper byte in your code sequence that you described,
I meant that I have tried your code sequence on a 68000 on a
VM03 card and the result in both cases is A0 = $ff001006 and
A0 = $ff001008 respectively.
I am one of the designers of the 68010 and the 68020. I do not
like it when you say that our processors have bugs in them. I
would be very happy to have any bugs that do exist reported so
that we could fix them immediately, but at the same time I would
expect that those making the reports review their problems to
ensure that there is indeed a problem. I would hope that you
are cognizant of the difference between a processor and a system
in which a processor resides. I have no question that when you
execute your code sequence you observe the results you described.
I agree that this is incorrect. This however this does not mean that
the 68000 behaves this way. By the way, the last bug on the 68000
was reported over 4 1/2 years ago.
Doug MacGregor {ihnp4,seismo,gatech,ctvax}!ut-sally!oakhill!doug