stevej@studsys.mu.edu (jovanovic) (12/15/89)
I have a Mac II that I'd like to upgrade, but I'm not sure about what the best way to do this is. I know the 68881 and 68882 are pin compatible, so replacing the 68881 with a 16MHz 68882 is no problem. But what about using a 25MHz 68882? Or would this show no real performance increase because of hardware-imposed wait states? Also, I'd like to add a PMMU, but would rather replace the 68020 directly with a 68030, although I don't know whether or not they're pin compatible. If they're not pin compatible, then I guess that means I have to go with a PMMU. But if by chance the 68030 is pin compatible, again, what real effect would there be in using a 25MHz chip rather than a 16MHz chip? Are wait states software- rather than hardware- imposed? Thanks for your help, and I'll summarize replies in a future posting. -steve. -- ----------------------------------------------------------------------- stevej@studsys.mu.edu Marquette University Electrical Engineering