Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site psivax.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!tektronix!hplabs!sdcrdcf!psivax!woof From: woof@psivax.UUCP (Hal Schloss) Newsgroups: net.micro.pc Subject: Re: Does DOS listen to LaserJets? Message-ID: <663@psivax.UUCP> Date: Sun, 18-Aug-85 13:52:26 EDT Article-I.D.: psivax.663 Posted: Sun Aug 18 13:52:26 1985 Date-Received: Sat, 24-Aug-85 19:38:20 EDT References: <596@alberta.UUCP> <13600015@hp-pcd.UUCP> <326@faron.UUCP> Reply-To: woof@psivax.UUCP (Hal Schloss) Organization: Pacesetter Systems Inc., Sylmar, CA Lines: 24 Summary: In article <326@faron.UUCP> kbb@faron.UUCP (Kenneth B. Bass) writes: >In article <13600015@hp-pcd.UUCP> john@hp-pcd.UUCP (john) writes: >> This must be a case of software inertia in action. Actually I think the "few >>chars" that are sent is caused by using a double buffered UART with software >>testing of the DTR status. > >This is a problem I've encountered practically every time I've had to >interface any two serial devices. That is, the problem of flow control. Well I have had similar experiences connecting our VAX 11/750 to a HP laserjet. The problem occurs with BSD 4.* for the same reasons as on MS-DOS. The fix was to install a Microbuffer from Practical Peripherals. After installing it as a "lump" in the cable all my problems went away. It responds to the Laserjet very quickly and doesn't overflow the printer's buffer, and the Microbuffer has enough buffer left when it sends a X-OFF as to not be a problem. -- Hal Schloss (from the Software Lounge at) Pacesetter Systems Inc. {trwrb|allegra|burdvax|cbosgd|hplabs|ihnp4|sdcsvax|aero|uscvax|ucla-cs| bmcg|sdccsu3|csun|orstcs|akgua|randvax}!sdcrdcf!psivax!woof or {ttdica|quad1|scgvaxd|nrcvax|bellcore|logico}!psivax!woof ARPA: ttidca!psivax!woof@rand-unix.arpa