From owner-freebsd-small Fri May 19 11:22:51 2000 Delivered-To: freebsd-small@freebsd.org Received: from mass.cdrom.com (adsl-63-206-88-224.dsl.snfc21.pacbell.net [63.206.88.224]) by hub.freebsd.org (Postfix) with ESMTP id 8238737BF86 for ; Fri, 19 May 2000 11:22:45 -0700 (PDT) (envelope-from msmith@mass.cdrom.com) Received: from mass.cdrom.com (localhost [127.0.0.1]) by mass.cdrom.com (8.9.3/8.9.3) with ESMTP id LAA09168; Fri, 19 May 2000 11:23:39 -0700 (PDT) (envelope-from msmith@mass.cdrom.com) Message-Id: <200005191823.LAA09168@mass.cdrom.com> X-Mailer: exmh version 2.1.1 10/15/1999 To: chip@chocobo.cx Cc: freebsd-small@freebsd.org Subject: Re: RS-485 on a PCM-4823 In-reply-to: Your message of "Fri, 19 May 2000 13:29:12 EDT." <20000519132912.A74009@setzer.chocobo.cx> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 19 May 2000 11:23:38 -0700 From: Mike Smith Sender: owner-freebsd-small@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > I've got an Advantech PCM-4823 (single board computer with ethernet, > VGA, IDE, 486 etc) running FreeBSD 4.0-RELEASE, and am trying to use > the boards second serial port in RS-485 mode. Everything works fine > if I use one of the RS-232 ports with an RS-485 adapter connected to > it, but when I try to use the built in 485, nothing seems to get > received, but transmission works fine (I can see it from the other > end.) After a while, the kernel starts complaining on the console > about > /kernel: sio1: 1069 more tty-level buffer overflows (total 3735) > and continues doing this for a little while, ending with a total of > 12567 buffer overflows. > > Anyone using RS-485 successfully or have any idea what I'm doing > wrong? The tty-level buffer overflows suggest that you're not actually reading from the port - there's a heap of data queued ready for someone to read from sio0, but nobody is. -- \\ Give a man a fish, and you feed him for a day. \\ Mike Smith \\ Tell him he should learn how to fish himself, \\ msmith@freebsd.org \\ and he'll hate you for a lifetime. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-small" in the body of the message