Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/3/84; site sesame.UUCP Path: utzoo!linus!philabs!cmcl2!seismo!harvard!talcott!sesame!slerner From: slerner@sesame.UUCP (Simcha-Yitzchak Lerner) Newsgroups: net.micro.pc Subject: Re: Does DOS listen to LaserJets? Message-ID: <272@sesame.UUCP> Date: Wed, 14-Aug-85 19:39:59 EDT Article-I.D.: sesame.272 Posted: Wed Aug 14 19:39:59 1985 Date-Received: Mon, 19-Aug-85 07:20:37 EDT References: <596@alberta.UUCP> <13600015@hp-pcd.UUCP> Organization: Lotus Development Corp Lines: 29 > > 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...... > > Many UARTS avoid this problem by providing a hardware holdoff input pin > (normally the CTS* input). These UARTs would test the pin before sending a > start bit and in the above case would pause before sending character N+2. > Character N+1 would be stored in the receiver's input buffer until read > so nothing would be lost. > > John Eaton > !hplabs!hp-pcd!john The only proble with CTS is that not all machines wire it thru. The reason for this is that there are a lot of UARTS out there with a bad bug: if CTS transitions mid-character xmision, the character is trashed. -- Opinions expressed are public domain, and do not belong to Lotus Development Corp. ---------------------------------------------------------------- Simcha-Yitzchak Lerner {genrad|ihnp4|ima}!wjh12!talcott!sesame!slerner {cbosgd|harvard}!talcott!sesame!slerner slerner%sesame@harvard.ARPA