Date: Fri, 25 Jun 1999 12:04:05 -0700 (PDT) From: Doug <Doug@gorean.org> To: Aaron Smith <aaron-fbsd@mutex.org> Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Serial Console Wierdness Message-ID: <Pine.BSF.4.05.9906251123410.21186-100000@dt054n86.san.rr.com> In-Reply-To: <199906221739.KAA13462@sigma.veritas.com>
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On Tue, 22 Jun 1999, Aaron Smith wrote: > (also see http://www.arctic.org/~aaron/tips/freebsd-serial-console) Great page, thank you. One suggestion I have is that you make the distinction between getting a login prompt on the com console and getting the boot messages to display on the com console more clear. The fact that those are two different things was not clear to me at all when I started working on this, and it's kind of an important distinction. :) Also, you might consider listing the getty stuff first. It's a lot easier to set that up and debug it since you don't have to keep rebooting, and once that's working getting the boot messages to display should be cake. Finally, you might want to mention that reading /usr/src/sys/i386/boot/biosboot/README.serial is a good idea, even though I wish that file had more details. :-/ I have a couple weird cases that I'd like to solicit comment on. First, I'm hooking up a new FreeBSD machine to the digiboard serial terminal at work. Everything works at 9600, including the bios boot messages from the Intel N440BX mb which supports serial console redirection. The problem comes when I try to raise the speed to 38400. The bios messages come through just fine at that speed, so the serial port and the digiboard support it. Also, if I have a keyboard plugged in, I see everything on the console that I should, and I get the login prompt. But when I unplug the keyboard and the -P option in /boot.config kicks in, the console messages come out in high ascii and even the getty prompt is scrambled. I took the following steps: edit /etc/make.conf rebuild boot blocks change my cuaa0 to std.38400 in /etc/ttys (ttyd0 didn't work with the digiboard) change digiboard speed to 38400 reboot I also tried the CONSPEED option in the kernel config (this is a -current system) still no joy. If I downgrade everything back to 9600 I'm back in business. I'm not sure if it should make a difference, but my cable has only 3 pins, Transmit and Receive crossed, and Ground linked directly. Also, the bios boot output and the digiboard both have XON/XOFF enabled, the rest of the options are the defaults. Yes I know that the obvious answer is "run it at 9600" which is ok with me, since we don't use the comconsole very often. However I find it kind of disturbing that it doesn't work at 38.4. :-/ Weird case number 2 is my two home machines. I've been trying to get a serial console going at home for months with no luck. Your suggestion of using kermit on both boxes has lead me in the right direction, so I'm more hopeful, but I'm still seeing weirdness. The headless (well, the old monitor is attached, for now but no kb) server is "slave," and my workstation is "Master." I have a commercial null modem cable connected to com1 (cuaa0) on slave and com2 on master. (Which reminds me, I think that one or the other of your kermit command lines needs to be changed, since generally you don't want to connect to com1 on both machines. :) When I type in kermit on master, I get nada, not even a local echo. When I type on slave it gets passed to master, but it's all scrambled. Sometimes it's alpha chars, sometimes it's all numbers, and sometimes it's high ascii, depending on how I set the flow control, speed, parity, etc. FWIW, slave is a very old (almost 5 years now) former P 90, now running an intel overdrive chip at 150. I overclocked this machine for years, but I stepped it down just in case that was the cause of my problems. Master is a shiny new box I built from scratch, using an Asus P2B mb, Celeron 300a, etc. I also overclocked this box when I built it, but also stepped it down for this. I have 2.2.8-Release on slave, -current (and formerly -stable, that didn't work for this either) on master. I tried to upgrade slave to 2.2.8-stable last night just in case, but the build failed (still working on that). I do plan to upgrade that box to 3-stable, but I can't do that yet. The immediate suspect is the cable, but when I built my own cable with just TR & G, I got the same results. I bought the commercial grade null modem cable thinking maybe I screwed something up, but it's no better. These are 9 pin serial ports on both boxes. I have no serial devices on slave, and a modem on master but it's set to com3, and I only use it in windows (master is a dual boot box). I'm wondering if the overclocking on the old P90 for so many years might have fried the uarts or something else related to the serial ports? If so, would getting an ISA serial port card and making that my serial console help any? I haven't tried making com2 my serial console yet, is that worth trying? I'm also going to get some new plugs/cables/etc. this weekend so that I can give making my own cable another try, just in case. Any help on either of these cases would be appreciated. Thanks, Doug -- On account of being a democracy and run by the people, we are the only nation in the world that has to keep a government four years, no matter what it does. -- Will Rogers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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