Date: Tue, 08 Aug 1995 10:16:32 -0500 From: "Eric L. Hernes" <erich@lodgenet.com> To: Michael Smith <msmith@atrad.adelaide.edu.au> Cc: ROBIN@ptnsct.nis.za (Robin Hunt), questions@freebsd.org Subject: Re: Accessing i/o map space with freebsd 2.1.0 Message-ID: <199508081516.KAA24583@jake.lodgenet.com> In-Reply-To: Your message of "Tue, 08 Aug 1995 23:40:48 %2B0930." <199508081410.XAA25745@genesis.atrad.adelaide.edu.au>
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> Robin Hunt stands accused of saying: > > > 2) If not, how can I use outb / inb without creating a bus error? > > Your program must be run as root; before performing any I/O operations, > open the file /dev/io. This action grants the process priveledges to > read and write directly to the hardware. > Does this really work? in /usr/src/sys/i386/i386/mem.c, it looks like it is #ifdef'ed out. at or about line 174: #ifdef notyet /* 386 I/O address space (/dev/ioport[bwl]) is a read/write access to seperate i/o device address bus, different than memory bus. Semantics here are very different than ordinary read/write, as if iov_len is a multiple an implied string move from a single port will be done. Note that lseek must be used to set the port number reliably. */ > > robin@ptnsct.nis.za > > -- > ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[ > ]] Genesis Software genesis@atrad.adelaide.edu.au [[ > ]] High-speed data acquisition and [[ > ]] realtime instrument control (ph/fax) +61-8-267-3039 [[ > ]] My car has "demand start" - Terry Lambert [[ > eric. -- erich@lodgenet.com erich@rrnet.com
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