Date: Sun, 4 Mar 2001 20:19:31 +1100 (EST) From: Bruce Evans <bde@zeta.org.au> To: John Baldwin <jhb@FreeBSD.ORG> Cc: The Hermit Hacker <scrappy@hub.org>, freebsd-current@FreeBSD.ORG Subject: RE: Problem with sio in -current ... possible cause of hangs? Message-ID: <Pine.BSF.4.21.0103042008330.6902-100000@besplex.bde.org> In-Reply-To: <XFMail.010303152518.jhb@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, 3 Mar 2001, John Baldwin wrote: > On 03-Mar-01 The Hermit Hacker wrote: > > If I plug my cable from /dev/ttyd0 -> /dev/ttyd1 on the same > > machine, run getty on /dev/ttyd1 and use kermit to connect to /dev/cuaa0, > > I get no response back, which is why I'm wondering about sio ... > > Try turning clocal off on the host and port you are running kermit on. Even Or just use /dev/cuaa*. > then, I still have yet to get getty to work at all, it's always stuck in > 'siodcd'. I've noticed via debugging output that the DCD change bit does raise > for a read, but that teh DCD status bit stays at zero the entire time. The This seems to indicate a cabling problem. DCD and DCD change shouldn't change for a read; they should only change when "carrier" changes. > sio driver seems to ignore the change bit and only read the status bit, so it > thinks DCD is never raised and hangs forever on open. Note that I can get a Very short transients in DCD would be missed by the driver. The DCD change bit is for not missing transients, but in normal modem applications missing transients is probably a feature. Anyway, it's not clear what state change should occur in the driver if the DCD state hasn't changed when the driver looks at it. > getty fine on a serial console, just not on a /dev/ttydX that's not also the > serial console. :( I've had this problem since before PRE_SMPNG however. Certainly a hardware problem :-). Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.21.0103042008330.6902-100000>