robp@gumby.network.com (Rob Peglar) (06/05/91)
In article <11845@hub.ucsb.edu> 6600joef@ucsbuxa.ucsb.edu (Joe Foster) writes: >In comp.unix.xenix.sco <chris@neabbs.UUCP> writes: > >>Who knows if it's possible to adress the PC-bus, when your >>computer is running under SCO Unix V/386 version 3.2? > >Only the UNIX kernel may directly access I/O ports and physical memory (in >case those cards are memory-mapped). Your friend will have to write drivers >for each interface card. There are plenty of books and things on this >subject, but writing device drivers is something like black magic. If these Not entirely true. Check out the vas() calls available in 3.2. These calls will allow user processes to access (physical) memory. Once the proper vas() calls have been executed (typically in a trivial device driver's init() portion) any user process can see the memory. Perfect for memory- mapped add-on cards, e.g. video. BTW, drivers aren't that hard. Just read the book(s) on them. No magic, just a different mind-set. Rob -- Rob Peglar Network Systems Corporation Internetwork Group 7600 Boone Avenue North robp@anubis.network.com Minneapolis MN 55428 (612)424-4888 x1028