Path: utzoo!attcan!uunet!samsung!zaphod.mps.ohio-state.edu!lavaca.uh.edu!uhnix1!sugar!ficc!peter From: peter@ficc.uu.net (Peter da Silva) Newsgroups: comp.unix.i386 Subject: Re: Need information on VP/IX or DosMerge ability to access odd hardware Keywords: Dos emulation in unix Message-ID: <5UI2815ggpc2@ficc.uu.net> Date: 27 Mar 90 13:26:37 GMT References: <31959@sequent.UUCP> Reply-To: peter@ficc.uu.net (Peter da Silva) Organization: Xenix Support, FICC Lines: 9 I don't know about VP/ix, but programs that need direct access to the serial port work under Merge/386. But there's a problem: System V/386 is not a real-time operating system, and communicating with a high-speed serial port is a real-time task. We used this combination in one system, and the number of dropped characters at 9600 baud was unacceptable. You can get away with taking over the interrupts under DOS because DOS doesn't have enough of an O/S to get in the way, but under UNIX the only way to do this is to write a UNIX device driver... which is the only sort of real time task a conventional UNIX system supports. -- _--_|\ `-_-' Peter da Silva. +1 713 274 5180. . / \ 'U` \_.--._/ v