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Home Forums 68kMLA Mac Plus and External SCSI — #13
Post #13 by Charlieman
Source Forum68kMLA
CategoryPeripherals
Post DateMon, 2 Nov 2009 - 19:32
Original URLhttps://68kmla.org/bb/threads/mac-plus-and-external-scsi.18659/
Post
As far as I know, the first Mac to actually have DMA (which the very first IBM PC had) was the IIfx and it was only used under A/UX.
The Mac II onwards were designed to use NuBus bus mastering for high speed data transfers. Both devices had to be on the NuBus, of course, and support bus mastering, at least as a slave. Possibly safer in a world of dodgy C programmers than DMA read/writes? Definitely more secure, as we have seen with modern FireWire implementations that allow the content of RAM to be dumped to an external disk.

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