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Path: sserve!newshost.anu.edu.au!munnari.oz.au!spool.mu.edu!howland.reston.ans.net!news.intercon.com!udel!newsserv.cs.sunysb.edu!home.stark.cs.sunysb.EDU!stark!stark!gene From: stark!gene@newsserv.cs.sunysb.edu (Gene Stark) Newsgroups: comp.os.386bsd.questions Subject: Re: help: FreeBSD serial ports hang Date: 22 Mar 94 07:08:19 Organization: Gene Stark's home system Lines: 24 Message-ID: <STARK!GENE.94Mar22070819@stark.uucp> References: <ron.764136167@wyvern.wyvern.com> NNTP-Posting-Host: home.stark.cs.sunysb.edu In-reply-to: ron@infi.net's message of Sun, 20 Mar 1994 04:02:47 GMT In article <ron.764136167@wyvern.wyvern.com> ron@infi.net (Ron Steele) writes: I can't get my serial lines working with FreeBSD. When trying to open a tty the program (kermit, cu, or a simple C program) just hangs. Oddly, that dt modem light does light, and goes out after ^c. A ^c results in an "interrupted system call" error. The system is a 486/25DX. The uart is a 16550af. There *is* a problem with the FreeBSD 1.1-BETA serial port driver, which causes hanging under some circumstances using some programs like PPP and UUCP (but not Kermit). Some of the FreeBSD serial port driver wizards are working on it, and my impression is that the cause of the problem is known. However, *your* problem sounds to me like you need a set of properly jumpered cables. It sounds like you are using cheap cables that do not jumper DCD. The serial port drivers in 1.1-BETA are such that opens to a port will block waiting for carrier. A workaround is to do "stty clocal" on the port. This will inhibit the wait for carrier. My advice, though, is to get proper cables. - Gene Stark --