Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!think!ames!cit-vax!news From: news@cit-vax.Caltech.Edu (Usenet netnews) Newsgroups: comp.sys.ibm.pc Subject: Re: LPT3 support Message-ID: <1348@cit-vax.Caltech.Edu> Date: Tue, 16-Dec-86 01:48:47 EST Article-I.D.: cit-vax.1348 Posted: Tue Dec 16 01:48:47 1986 Date-Received: Wed, 17-Dec-86 04:23:38 EST References: <133@parcvax.Xerox.COM> <295@ima.UUCP> Reply-To: tim@tomcat.caltech.edu (Tim Kay) Distribution: na Organization: California Institute of Technology Lines: 19 Summary: Why does the printer interface lose interrupts? Organization : California Institute of Technology Keywords: printer interface, interrupts From: tim@tomcat.Caltech.Edu (Tim Kay) Path: tomcat!tim In article <295@ima.UUCP> johnl@ima.UUCP (John R. Levine) writes: >Due to the poor design of the IBM printer interface, you can't run the printer >with interrupts -- there's no way to keep from losing the interrupts. Programs Could you elaborate on this? I wrote a printer device driver that had some buffering. This can speed up output to the Epson by a factor of two by overlapping the computation of the next line with the printing of the current one. The driver relied on printer interrupts. It worked reliably for most applications. However, occasionally, an interrupt was lost. It was rather annoying. Timothy L. Kay tim@csvax.caltech.edu Department of Computer Science Caltech, 256-80 Pasadena, CA 91125