Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!samsung!umich!sharkey!fmsrl7!wehr From: wehr@fmsrl7.UUCP (Bruce Wehr ) Newsgroups: comp.sys.hp Subject: Re: Problem connecting LJIII to 9000-350... Summary: Turn modem control off Message-ID: <39464@fmsrl7.UUCP> Date: 4 Apr 91 16:22:18 GMT References: <41572@ucbvax.BERKELEY.EDU> Organization: Ford Motor Company, Scientific Research Labs, Daerborn, MI Lines: 30 In article <41572@ucbvax.BERKELEY.EDU>, luism@genesis.Berkeley.EDU (Luis Miguel) writes: > A ls -l on /dev/lj3 shows: > > /dev/lj3 crw-rw---- 2 lp sys 1 0x090000 > > I do the required "stty xxxxxxx 9600 xxxxxx < /dev/lj3" which the > manual indicates. This call just hangs (I leave it in the background). Your first clue that something is wrong is that the 'stty' command hangs - it shouldn't. It's hanging because the driver is paying attention to the modem control lines (the open(2) issued to "/dev/lj3" [by the shell as a result of the redirection] will hang until DTR comes up). To convince the driver to ignore modem control lines, change the last digit in the minor number to 4 (0x090004). Port parameters get set to default values (300 for baud rate) when the first process opens it. So, you must open the port and keep it open before you issue the 'stty' command (otherwise, the 'stty' command will open the port, set the baud rate, and then close the port - nullifying its effect). This is why the manual suggests issuing a 'sleep 20000000