From owner-freebsd-multimedia Fri Mar 28 08:54:51 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id IAA20323 for multimedia-outgoing; Fri, 28 Mar 1997 08:54:51 -0800 (PST) Received: from Ilsa.StevesCafe.com (sc-gw.StevesCafe.com [205.168.119.191]) by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id IAA20318 for ; Fri, 28 Mar 1997 08:54:43 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by Ilsa.StevesCafe.com (8.7.5/8.6.12) with SMTP id JAA25681; Fri, 28 Mar 1997 09:54:36 -0700 (MST) Message-Id: <199703281654.JAA25681@Ilsa.StevesCafe.com> X-Authentication-Warning: Ilsa.StevesCafe.com: Host localhost [127.0.0.1] didn't use HELO protocol X-Mailer: exmh version 1.6.5 12/11/95 From: Steve Passe To: Richard Tobin cc: multimedia@freebsd.org Subject: Re: Tuner AFC In-reply-to: Your message of "Fri, 28 Mar 1997 13:05:41 GMT." <27629.199703281305@pitcairn.cogsci.ed.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 28 Mar 1997 09:54:35 -0700 Sender: owner-multimedia@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Hi, > It turns out that some of the channels here aren't on precisely the > official frequencies, so I wrote a program to do AFC. > > The AFC works using the 3 bottom bits of the tuner status register. > When it's centred, they are 0 1 0. 1 0 0 means it's too low, 0 0 1 > too high. The TEMIC datasheet refers to a 5-level ADC suggesting > that it might return 1 1 0 or 0 1 1 but that doesn't seem to happen > for me. according to the philips datasheet for the TSA5522 (ie the PLL being addresses) the legal values are 0 thru 4. according to the philips datasheet for the tuners it breaks down like this: Frequency (kHz): Value (binary): -125.0 000 -62.5 001 0.0 010 +62.5 011 +125.0 100 -- Steve Passe | powered by smp@csn.net | Symmetric MultiProcessor FreeBSD