Tabakal@UB.CC.UMICH.EDU (10/31/90)
Well, here we go again. The continuing tales of the ASIC high
speed 65816 chip as dictated to me by Tony Fadell. This chapter
is in response to some of Jawaid Bazyar's requests for features
to implement a multi-tasking operating system for the GS:
Thanks for the news!...
Let me clarify some things first.. We did not implement the
ABORT pin on the '816 because the original version of the
'816 had problems with abort during REP,SEP, and 2 other
addressing modes (I don't remember them off hand) We chose
instead to put in a page mode pin .. in the words of Jawaid
"high speed bank memory access." This will allow you to only
have to specify part of the address instead of the whole
address to make writes to memory up to 8 times faster. Apple
told us if they had such a pin they could make the GS run at
8Mhz on the motherboard with little change to the existing
design. As far as the Motorola parts are concerned I have
not looked at their spec sheets. I would think it is very
possible to integrate one of the chips.
The chips are layed out and are now in fab.. More details to
come..
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Todd A. Bakal All snappy sayings aside,
U of M Apple User's Group !Index will be updated
Ann Arbor, Michigan ASAP or my name's not...
Internet: Tabakal@ub.cc.umich.edu FTP: ummts.cc.umich.edu
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