Path: utzoo!utgpu!watmath!clyde!att!rutgers!apple!vsi1!wyse!mips!sultra!dtynan From: dtynan@sultra.UUCP (Der Tynan) Newsgroups: comp.unix.microport Subject: Re: Microport V/AT Printer Spooler non-Problem Summary: "Centronics" just describes the interface. Keywords: Microport lp hangs non-bug Message-ID: <2704@sultra.UUCP> Date: 5 Dec 88 23:31:50 GMT References: <1559@ssc.UUCP> Organization: Tynan Computers, Sunnyvale, CA Lines: 25 In article <1559@ssc.UUCP>, fyl@ssc.UUCP (Phil Hughes) writes: > > About 1 hour later they called back. Things had stopped working. An > lpstat showed the old "printer spooler bug" - idle printer but files in > the queue. This is only one data point but it sounds to me like there is > a difference between Centronics and Centronics compatible. > > Phil Hughes, SSC, Inc. P.O. Box 55549, Seattle, WA 98155 (206)FOR-UNIX One thing I would check for, is the printer buffering. A "Centronics" interface is just that. An interface. A lot of older printers don't have any kind of buffering, which means that you have to feed it data at the print rate. This can result in an interrupt-per-character type arrangement, which can kill even the best operating system :-( On newer printers, once you get the interrupt, you can handshake in a lot of chars at once, meaning that the latency is a lot less. It seems to me, that the driver/printer interface is getting confused. This could be a result of heavy interaction. Note however, that I don't use Microport UN*X, so the above is nothing more than idle speculation, given the information posted. Hope it helps... - Der -- dtynan@zorba.Tynan.COM (Dermot Tynan @ Tynan Computers) {apple,mips,pyramid,uunet}!Tynan.COM!dtynan --- If the Law is for the People, then why do we need Lawyers? ---