From owner-freebsd-hackers Sun Sep 30 12:30:22 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from guru.mired.org (okc-94-248-46.mmcable.com [24.94.248.46]) by hub.freebsd.org (Postfix) with SMTP id C0E5F37B40A for ; Sun, 30 Sep 2001 12:30:19 -0700 (PDT) Received: (qmail 78239 invoked by uid 100); 30 Sep 2001 19:30:19 -0000 From: Mike Meyer MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15287.29386.998663.37631@guru.mired.org> Date: Sun, 30 Sep 2001 14:30:18 -0500 To: Bart Kus Cc: hackers@freebsd.org Subject: Re: sio modification In-Reply-To: <200109301003.06903@EO> References: <200109301003.06903@EO> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`;h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Bart Kus types: > manipulates the CD line of the serial port it plugs into. Afaik, the UART > itself is capable of generating an interrupt whenever CD changes. The > problem is, sio.c doesn't support this feature. I'm stuck with polling the > status register to find out the state of CD. Not a very good solution for a > daemon that's supposed to run in the background all the time, especially > since the CD line will be toggled at about 40kHz (I think that's the remote > control frequency standard). Perhaps I'm wrong about the 40kHz figure. It looks like you've already got a solution to this problem, and this won't be very useful if the 40kHz figure is right, but I figured I might mention it anyway. Have you thought about using the feature of the callin device of the "open" call blocking until it gets CD? You should then get a SIGHUP when CD drops. http://www.mired.org/home/mwm/ Q: How do you make the gods laugh? A: Tell them your plans. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message